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Posted By: gan the mystery of time and light - 07/21/10 02:40 AM
I need anyone who interest to give me a comment... If the atomic mass of time is <= the atomic mass of light, or the speed of time is <= the speed of light, then if we can breakthrough the constant speed of light(velocity) ; we can breakthrough the constant of time ( that means we can travel past or future ) as well ... hope you all can figure out and give some comments
Posted By: kallog Re: the mystery of time and light - 07/21/10 04:22 AM
How do you define the speed of time? dt/dt is just 1 no matter how 'fast' it goes.

Time isn't atoms so it can't have an atomic mass, nor can light.

But yea I think if you go faster than light you're supposed to travel back in time or something.
Posted By: gan Re: the mystery of time and light - 07/21/10 12:29 PM
ooo thanks... but light can be measure by E=\mc2.... then how to measure time???
Posted By: redewenur Re: the mystery of time and light - 07/21/10 12:41 PM
Get a watch or, better still, a strontium atomic clock:

http://www.nist.gov/public_affairs/clock/clock.html

"The JILA strontium clock would neither gain nor lose a second in more than 200 million years, compared to NIST F-1's current accuracy of over 80 million years." - Feb 14, 2008

http://www.youtube.com/watch?v=4d9IU-Dyemo
Posted By: ImagingGeek Re: the mystery of time and light - 07/21/10 02:09 PM
You are making a common, but fatal error in your assumptions. Time is not a constant; rather, time is variable and it is relative to your reference frame. Ergo, there is no fundamental "unit" or "mass" or "speed" of time.

At sufficient velocity (speed of light) there is <u>no</u> time, although it is impossible to get mass upto that speed. However, at speeds close to the speed of light, time slows to near-infinite slowness...

Bryan
Posted By: pokey Re: the mystery of time and light - 07/22/10 01:51 AM
Also proximity to mass (gravitational field) also slows time.
Posted By: gan Re: the mystery of time and light - 07/22/10 02:02 AM
thanks... That means that are imporsible to breakthorugh time although we can travel as light...
Posted By: gan Re: the mystery of time and light - 07/22/10 02:11 AM
that means time is same as atom's frequency... what if we breakdown the constant of atom's vibration ??? breakdown the constant of time....
Posted By: redewenur Re: the mystery of time and light - 07/22/10 12:44 PM
Originally Posted By: ImagingGeek
You are making a common, but fatal error in your assumptions. Time is not a constant; rather, time is variable and it is relative to your reference frame.

Yes, although it's worth pointing out that time is, indeed, constant within your frame of reference, and that the passage of time for other frames of reference can, theoretically, be ascertained by applying relativity theory.

Originally Posted By: gan
that means time is same as atom's frequency

No, it doesn't mean that. You might equally suggest that time is the same as a metronome's frequency - but speeding up the metronome doesn't make the music lesson shorter.
Posted By: socratus Re: the mystery of time and light - 07/23/10 01:16 PM
Originally Posted By: ImagingGeek
You are making a common, but fatal error in your assumptions. Time is not a constant; rather, time is variable and it is relative to your reference frame. Ergo, there is no fundamental "unit" or "mass" or "speed" of time.

At sufficient velocity (speed of light) there is <u>no</u> time, although it is impossible to get mass upto that speed. However, at speeds close to the speed of light, time slows to near-infinite slowness...

Bryan

==============.
Time, Space and Quantum of Light. / My opinion./
http://www.paricenter.com/forum/index.php?topic=61.0;wap2
==.
S.
Posted By: kallog Re: the mystery of time and light - 07/24/10 03:54 AM
Originally Posted By: gan
that means time is same as atom's frequency... what if we breakdown the constant of atom's vibration ??? breakdown the constant of time....


You seem to be attaching some fundamental importance to atoms. They're just structures that happen to have formed, not particularly different from molecules, stars, galaxies, people, etc. Once upon a time there were no atoms in the universe. They don't have to be there any more than stars have to be there.
Posted By: gan Re: the mystery of time and light - 07/24/10 07:13 AM
so long wo... but useful... that means light and speed have relationship la..... if like that, Albert Einstein say nothing can faster than light wo.... then we cant breakthrough time lo....
Posted By: redewenur Re: the mystery of time and light - 07/24/10 11:39 AM
Originally Posted By: gan
then we cant breakthrough time

Yes and No. The norm, of course, is that we travel forward in time at a constant rate within our local spacetime frame of reference; but when we move relative to an object outside our frame of reference, we travel forward in time relative to that object. We don't usually have evidence of this because the effect is very close to zero at day-to-day, earthbound speeds, but it becomes significant as an object's relative velocity approaches that of light (as do particles at LHC). So, travelling forward in time is a reality. Going backward in time is the problem; it's considered by many to be impossible for reasons of both science and philosophy. Although there are serious ideas about how it might be achievable, there's no foreseeable feasible experiment.

Originally Posted By: gan
Albert Einstein say nothing can faster than light
Right. One way to see it is: as an object approaches light velocity (called 'c'), it increases in mass. So it requires ever increasing energy to accelerate it. If it could reach c, it would have infinite mass, and so would have required infinite energy to do so.
Posted By: gan Re: the mystery of time and light - 07/24/10 02:14 PM
ooo... then we really need to work hard to take out this... but I only a student... cant do anything instead of study hard... Is there any machine that can contact with the ghost??? I think have scientist investigated it...
Posted By: redewenur Re: the mystery of time and light - 07/24/10 03:03 PM
Originally Posted By: gan
Is there any machine that can contact with the ghost?
That's Not-Quite-Science territory. Maybe you'd like to open a new thread in that section.
Posted By: kallog Re: the mystery of time and light - 07/25/10 07:40 AM
Originally Posted By: redewenur

considered by many to be impossible for reasons of both science and philosophy. Although there are serious ideas


There's a fairly simple theoretical way to fake it, which might be good enough for some purposes.

Just do the twin paradox! You could travel hundreds of years into the future, and when you return to Earth, people would meet someone from the past, in his ancient spaceship, with his memories of the world that they only know from history books.
Posted By: redewenur Re: the mystery of time and light - 07/25/10 10:33 AM
Originally Posted By: kallog
Just do the twin paradox!
Well, yes; although the twin paradox is defunct in the light of experiment results. Not that I have a deep insight into why one twin moves through time faster than the other. Acceleration, sure. Inertial frames, sure. But why? - Oh to be a mathematician versed in tensor calculus! At least I could confidently kid myself that I understood it all.
Posted By: kallog Re: the mystery of time and light - 07/25/10 11:52 AM
Originally Posted By: redewenur
Originally Posted By: kallog
Just do the twin paradox!
Well, yes; although the twin paradox is defunct in the light of experiment results.


You mean it doesn't work?? I didn't think it'd ever been properly tested. I know there's been experiments with atomic clocks on planes, and GPS satellites and all that, but they're slightly different situations.
Posted By: redewenur Re: the mystery of time and light - 07/25/10 12:51 PM
Originally Posted By: kallog
You mean it doesn't work??
What I mean is that the 'paradox' isn't actually a paradox. According to Special Relativity, the travelling twin should age less. The time dilation is predicted, and has been tested and verified not only by the clocks on planes, but by various other means since the 1940s, and continuously in particle accelerators since the 1950s; or so I'm reliably informed (as they say).
Posted By: gan Re: the mystery of time and light - 07/25/10 02:12 PM
I don think we can travel so far... it's only a prediction, isn't it???
Posted By: redewenur Re: the mystery of time and light - 07/25/10 05:37 PM
Originally Posted By: gan
I don think we can travel so far... it's only a prediction, isn't it???

It remains only a prediction because nobody's actually done it.

Likewise: 'If you fall into the sun you'll burn up'. That, too, is only a prediction, because nobody's done that either.

Both, though, are constantly proven correct in principle.
Posted By: Bill S. Re: the mystery of time and light - 08/21/10 11:30 PM
Two points that arise out of the foregoing discussion may be worth considering.
1. Einstein did not say that no material object could travel faster than light; what SR forbids is the acceleration of any object through space from sub-light speed to super-light speed. Current thinking about the expanding Universe has distant galaxy groups moving away from us faster than light, because they are not moving through space; space is expanding and carrying them with it.
2. There seems to be a tacit acceptance that time “passes”, but if time moves, to what is that movement relative? Surely it is more reasonable to think of time as a static entity through which we all move. This leads to the possibility that everything moves through spacetime at the same speed; the speed of light. Light does all its travelling through space, which means it is static in time, whereas we do most of our travelling through time, and a very limited amount through space, because we are so slow (relatively speaking, of course).
Bill S.
Posted By: Bill S. Re: the mystery of time and light - 08/22/10 03:17 PM
"Junior member"....at 70! I like it.
Posted By: redewenur Re: the mystery of time and light - 08/22/10 06:26 PM
Originally Posted By: Bill S.
1...galaxy groups...space is expanding and carrying them with it.
Right, and not understood by people who see the Big Bang as an explosion of material through space.

(2) seems a bit confused (confuses me anyway smile ):

'everything moves through spacetime at...the speed of light'

- Photons do. We don't.

'Light does all its travelling through space, which means it is static in time'

- Time passes as photons go from A to B.

'we do most of our travelling through time, and a very limited amount through space'

- When we travel faster through space we also travel faster through time?
Posted By: Kate Re: the mystery of time and light - 08/23/10 01:18 AM
""Junior member"....at 70! I like it."

Glad that you like it;-)

Our new moderating system will allow us to get rid of spam before it shows up but we had to rejig the membership system... so now you have, perhaps, a bit of a misnomer... but hopefully it makes you feel young again!:-)
Posted By: redewenur Re: the mystery of time and light - 08/23/10 07:35 AM
Originally Posted By: Bill S.
"Junior member"....at 70! I like it.

That's nothing, Bill. When you reach Megastar they give you a limo and chauffeur.
Posted By: Bill S. Re: the mystery of time and light - 08/24/10 01:18 PM
Time passes as photons go from A to B.

Time passes in our frame of reference, but what is "true" in one F of R is not necessarily the case in another.

When we travel faster through space we also travel faster through time?

If we could travel at superluminal speed we would be travelling backwards in time, or so the popular science books tell us. If the speed of light is the changeover point, then logically we must be stationary relative to time when travelling at "c", in the same way that a vehicle that is travelling forward must stop before it can reverse. If we are stationary in time, but moving in space, we must be in more than one place at a time. It follows that a photon would be at A and B at the same time, in its own F of R.
Posted By: redewenur Re: the mystery of time and light - 08/25/10 12:22 AM
"It follows that a photon would be at A and B at the same time, in its own F of R."

Yes, Bill, fascinating isn't it. Theory does appear to lead to that conclusion - that each photon (in its own frame of reference, as you say) must exist at every point in the universe; and one might say that they inhabit eternity. A discussion here that you might find interesting:

http://www.thenakedscientists.com/forum/index.php?topic=18981
Posted By: Bill S. Re: the mystery of time and light - 08/25/10 07:01 PM
Redewenur. Thanks for the link. I have not struggled through all 5 pages yet, but I found a quote that says exactly what I was trying to put into words. I hope Lee E will not mind if I reproduce part of it.

"Although we can move through three spatial dimensions, at any point in time the movement vectors for all three spatial directions can be summed to a single vector. Thus movement is essentially in a single direction and can be expressed by a single value, just as when we drive heading North-West we don't say we are driving West at x mph and North at y mph; we just use the summed vector.

With movement induced time dilation, the same thing is happening, except this time the two vectors being summed are the summed spatial movement vector and the temporal movement vector. The reason we get time dilation is because it is the sum of these two vectors, spatial and temporal, which cannot exceed 'c', so as the spatial movement vector increases, the temporal vector must decrease. With zero spatial movement then, we move temporally at 'c', which in turn implies we have zero length in that direction."
Posted By: redewenur Re: the mystery of time and light - 08/26/10 01:49 AM
"With zero spatial movement then, we move temporally at 'c'"

I take 'zero spatial movement' to mean what it says, i.e. not moving at all (except in time) - and nothing ever does move in it's own F of R, but only relative to other things.
Posted By: Bill S. Re: the mystery of time and light - 08/26/10 03:41 PM
"nothing ever does move in it's own F of R"

I see what you mean, but isn't this taking a somewhat restricted view of a F of R?

I am sitting down, if I stand up I am moving, but I do not move out of my frame of reference. Admittedly, my movement is measurable only in relation to other objects, but I still perceive myself as moving, while still being in my own frame of reference.
Posted By: redewenur Re: the mystery of time and light - 08/27/10 12:04 AM
When you change posture from sitting to standing, various parts of your body are in motion relative to each other. That is to say, each of those parts exists within its own F of R.
Posted By: kallog Re: the mystery of time and light - 08/28/10 11:36 AM
Originally Posted By: redewenur
When you change posture from sitting to standing, various parts of your body are in motion relative to each other. That is to say, each of those parts exists within its own F of R.


Yea but more relevently you're accelerating. If you stand up without accelerating (assuming no relative motion of body parts), then you wouldn't perceive yourself as moving, rather you'd feel the room was moving around you.

I think that very clear explanation of time and space vectors implied the thing's being viewed from some arbitrary reference frame, not necessarily its own.
Posted By: redewenur Re: the mystery of time and light - 08/28/10 12:51 PM
kallog: "rather you'd feel the room was moving around you"

Yes, that's commonly known as 'the morning after syndrome' smile . - or you could achieve a similar effect by reading through this:

http://www-history.mcs.st-and.ac.uk/HistTopics/Newton_bucket.html

But seriously, yes, acceleration applies to any object moving at non-constant velocity - which includes all things in a gravitational field, so that's just about everything I suppose. Which is why I find the 'Newton's Bucket' so interesting. Mach's ideas on rotational acceleration (taken up by Einstein as 'Mach's principle') are also worth a bit of thought.

"In 1985 further progress by H Pfister and K Braun showed that sufficient centrifugal forces would be induced at the centre of the hollow massive sphere to cause water to form a concave surface in a bucket which is not rotating with respect to the distant stars. Here at last was a form of the symmetry that Mach was seeking."

Weird, innit. And dead fascinating.
Posted By: Bill S. Re: the mystery of time and light - 08/28/10 01:55 PM
Dragging the discussion back in the direction of the F of R, one has to wonder who, or what, occupies my F of R? The simple answer might seem to be "I do", but as pointed out above, parts of me move relative to other parts, and there can be no movement within a F of R. Even my brain cannot occupy my F of R, because there is activity in there (I'm sticking to that, in spite of any contrary evidence). Every synapse has its own activity. Following this line of thought, it begins to look as though no physical entity can claim to occupy a F of R. Increasingly, the F of R looks like the "present", the closer you try to look at it, the more elusive it becomes.
Posted By: kallog Re: the mystery of time and light - 08/29/10 01:30 AM
Originally Posted By: redewenur

"In 1985 further progress by H Pfister and K Braun showed that sufficient centrifugal forces would be induced at the centre of the hollow massive sphere to cause water to form a concave surface in a bucket which is not rotating with respect to the distant stars. Here at last was a form of the symmetry that Mach was seeking."


I find it all quite uninteresting. The frame dragging isn't really relevant. If you want a bucket that's not rotating relative to the stars, and yet the water has a concave surface, it's easy, just set up some sort of gravitational field which does that. It could be by frame dragging, or be classical gravity.

Although I suppose it shows that just looking at the shape of the water can't tell you if it's accelerating or in a gravitational field. That just comes back to the equivalence principle which is kind of fascinating but also kind of obvious.

Posted By: kallog Re: the mystery of time and light - 08/29/10 02:58 AM
Originally Posted By: Bill S.
claim to occupy a F of R. Increasingly, the F of R looks like the "present", the closer you try to look at it, the more elusive it becomes.


True. But for many purposes you can ignore internal motion. Even tho there's thermal motion of the atoms in a brick, their overall momentum adds up to the momentum of the whole thing.

Inertial frames of reference are just convenient for simplifying things like SR does. If we were all really smart we could do away with them and treat everything and it's parts as accelerating in whatever way they are.
Posted By: redewenur Re: the mystery of time and light - 08/29/10 04:36 AM
Originally Posted By: kallog
I find it all quite uninteresting. The frame dragging isn't really relevant
Uninteresting? - sure, whatever lights your fire; but [frame dragging] 'not relevant'? - any distortion of spacetime is relevant to frames of reference.

Originally Posted By: kallog
Inertial frames of reference are just convenient for simplifying things like SR does.
Convenient, and actual - and I would hazard a guess that Bill's intention is to try to gain insight into what happens specifically in terms of frames of reference.
Posted By: kallog Re: the mystery of time and light - 08/29/10 11:59 AM
Originally Posted By: redewenur
Uninteresting? - sure, whatever lights your fire; but [frame dragging] 'not relevant'? - any distortion of spacetime is relevant to frames of reference.


It sounded like the article used that frame dragging to show that rotation is relative to the massive things around it. But surely it isn't?

Or is it really? Do we feel centrifugal force on a roundabout because it's spinning relative to loads of massive material in the universe? And it would be equally valid to say that other stuff is spinning while we're standing still? That's amazing. But if it's not that then the whole frame dragging thing is going off on a tangent for the article, which is what I found a bit frustrating.

Originally Posted By: redewenur

azard a guess that Bill's intention is to try to gain insight into what happens specifically in terms of frames of reference.


Yea and I think that's what he's done, reminded us that pretty much everything is accelerating pretty much all the time, at least its constituent parts are.
Posted By: Bill S. Re: the mystery of time and light - 08/29/10 01:36 PM
"Do we feel centrifugal force on a roundabout because it's spinning relative to loads of massive material in the universe? And it would be equally valid to say that other stuff is spinning while we're standing still?"
Could it not be argued that on the roundabout we know we are moving because we have experienced acceleration, whereas the world around us has not. I have never been very happy with that reasoning when applied to the twin paradox, so I would be interested to see someone shoot it down.
Posted By: kallog Re: the mystery of time and light - 08/30/10 01:00 AM
Originally Posted By: Bill S.

Could it not be argued that on the roundabout we know we are moving because we have experienced acceleration, whereas the world around us has not.


Sorry but it's exactly how I thought things worked too. Tho there is that possibility the roundabout might be enclosed in a massive spinning sphere, so we'd feel acceleration even tho we're not rotating relative to the distant stars. But it seems like more of a special theoretical case rather than what actually happens.
Posted By: Bill S. Re: the mystery of time and light - 08/31/10 01:10 PM
I am still not happy about the acceleration argument. Consider this thought experiment. A spacecraft passes the Earth at 60% of c. On the craft is a pair of twins. As the craft passes the Earth, one twin heads for Earth in a shuttle, and lands. The craft continues. Later, it executes a wide turn with no change of speed. Obviously, the manoeuvre causes a velocity change, but this is kept to a minimum, and is probably no greater than the positive and negative acceleration experienced by the other twin. After a journey of 10 light years the craft passes Earth, as it does so, time dilation tells us that the twin on the space craft is younger than the one on Earth, but how can this be attributed to acceleration?
Posted By: redewenur Re: the mystery of time and light - 09/01/10 03:43 AM
Originally Posted By: kallog
Originally Posted By: Bill S.

Could it not be argued that on the roundabout we know we are moving because we have experienced acceleration, whereas the world around us has not.


Sorry but it's exactly how I thought things worked too. Tho there is that possibility the roundabout might be enclosed in a massive spinning sphere, so we'd feel acceleration even tho we're not rotating relative to the distant stars. But it seems like more of a special theoretical case rather than what actually happens.

Seems to me that either one accepts or does not accept that there is no single reference point from which all motion is measured - i.e., that all motion is relative. If one takes rotational velocity to be an exception, then one has the task of explaining why. But hey, I reserve the right to be wrong twice before breakfast smile
Posted By: kallog Re: the mystery of time and light - 09/01/10 01:05 PM
I don't think we can have the choice for constant velocity motion. Unless we imagine something for which there's no evidence.

The way I see acceleration is your velocity changes from what it was before. So everybody knows it's changed. Not everybody may agree on how fast it was before, but at least they agree how much it changed by.

So it doesn't require any special reference frame. If you like, one usable frame would be the intertial frame of the previous state of the object before its speed changed.
Posted By: Bill S. Re: the mystery of time and light - 09/01/10 01:47 PM
I am not questioning the relativity of motion, nor doubting that acceleration can occur without a change of speed. Neither response has actually addressed the fundamental questions in my previous post. I.e. Is the more travelled twin younger that the one who hopped off onto the Earth? If so, why? Both have experienced acceleration. The major difference between them is a period of travel at a speed that has remained constant relative to the Earth.
Posted By: redewenur Re: the mystery of time and light - 09/02/10 12:39 AM
Needless to say I have an opinion, Bill, but it would be unreliable in the absence of the maths to back it up. It might be difficult to find a suitably qualified person who can give you a definitive answer, but you could try Ask a Scientist:

http://www.newton.dep.anl.gov/aas.htm
Posted By: socratus Re: the mystery of time and light - 09/02/10 01:05 PM
The mystery between Time and Quantum of light.
===.
When quantum of light moves with constant speed c=1
the Time is constantly frozen,
Questions.
How does constantly frozen Time broke and variable time appear?
In which Reference frame the frozen Time exist?
In which Reference frame the variable time exist?
What is interaction between these two systems?
#
According to SRT time depends on speed.
According to GRT time depends on mass.
And I ask maybe mystical , maybe scientific question:
Does quantum of light have influence on the time?
===.
Israel Socratus.
Posted By: Bill S. Re: the mystery of time and light - 09/03/10 10:18 PM
Well done Socratus! You have brought us back, at least close to the point where Gan set things in motion.
With regard to your questions, I would suggest trying to think of time as a static entity, through which we are moving. In that way, time does not have to change from being “frozen” to being variable, any more than space has to change when we start to move about.
Only in the frame of reference of an observer does time appear to change. True, relativity tells us that an observer in motion relative to something else can with equal validity consider herself to be moving, or the “something else” to be moving, but in the case where the “something else” is time that may make no more sense than Einstein’s alleged question: “Does Oxford stop at this train?”
A photon travelling through a vacuum must, as you say, be stationary in time. However, if it passes, for example, through the Earth’s atmosphere it slows slightly, thereby experiencing some passage through time in its F of R, but time remains unchanged.
I would argue that time does not depend on either speed or mass. Only an observer’s perception of time is altered by these things, and then only in his F or R.
Here’s a question though. The photon in a vacuum must be at every point on its journey at the same time. If it is going from A to B, it must be at B at the same time that it leaves A. Now suppose that between A and B it passes through the Earth’s atmosphere which slows it down slightly, so it experiences a passage through time, thus delaying its arrival at B. Now we have a situation in which the photon is at A and B, in its F of R, at the same time; but it also arrives at B shortly after leaving A, also in its own F of R. What is more, this situation is not improved if we reason that we cannot know anything about what the photon does on its way between A and B. How can it arrive in one place at two different times in its own F of R?
Posted By: Bill S. Re: the mystery of time and light - 09/03/10 10:21 PM
Sorry, I seem to have duplicated my last post; must be something to do with my lack of technical know-how.
Posted By: kallog Re: the mystery of time and light - 09/04/10 05:30 AM
Originally Posted By: Bill S.
Sorry, I seem to have duplicated my last post; must be something to do with my lack of technical know-how.


Haha. When I do that I prefer to blame the lack of human know-how of the people who developed the software. They should have made sure you can't accidentally do that.

Anyway, back to the twins. The situation isn't symmetric. The one who continued on still had to accelerate to turn around. If he did it slowly then he experienced a lower acceleration, but spent a longer time doing it. That means you can't necessarily make the effect arbitrarily small. If he could turn around with a small acceleration for a short time, then it would be reasonable to say that's as good as no acceleration at all.
Posted By: kallog Re: the mystery of time and light - 09/04/10 05:35 AM
Originally Posted By: Bill S.

going from A to B, it must be at B at the same time that it leaves A.

Now suppose that between A and B it passes through the Earth’s atmosphere which slows it down slightly, so it


If it slows down on the way then it can no longer be at A and B at the same time.

Or are you saying, when it starts out it 'thinks' it's already at B because it doesn't see the Earth in the way. Then somebody puts Earth in its path, so suddenly it has to not be at B anymore.
Posted By: Bill S. Re: the mystery of time and light - 09/04/10 12:46 PM
Kallog. I was not looking for a situation that could be equated to "no acceleration at all", but in this scenario both twins have experienced acceleration. I don't have the maths to work out which would have the greater effect, so let's try a different tack. If the travelling twin keeps going in a straight line at constant speed, at the point at which he is 10ly from Earth, is he younger than the other twin? There may be no way he could know that for sure, but the age difference should be there, unless we are saying that the age difference exists only if it can be directly observed.

As far as the photon is concerned, I am not saying that "when it starts out it 'thinks' it's already at B"; I am saying that it is at A and B, in its own F of R, in a sort of infinite "present". There is no need for someone to put the Earth in the way. The photon would have to be aware of the presence of the Earth at the outset, and would have no time in which to be aware. I think I am beginning to answer my own question, so I shall stop rabbiting, and do some thinking.
Posted By: kallog Re: the mystery of time and light - 09/04/10 03:39 PM
Originally Posted By: Bill S.

travelling twin keeps going in a straight line at constant speed, at the point at which he is 10ly from Earth, is he younger than the other twin? There may be no way he could know that for sure, but the age difference should be there, unless we are saying that the age difference exists only if it can be directly observed.


Hmm. If the travelling one stopped when he got to 10ly, then we could know for sure because they'd both be in the same reference frame. One way is to have clocks strewn about the universe, all stationary in the Earth's reference frame, then no matter how far away you are, you can tell the time. Not that I have an answer, but it'd be nice to figure one out.

If the travelling one didn't stop, then I'm pretty sure the people on Earth, looking through their telescopes and accounting for light travel time, would see him as being younger than the twin on Earth. But here the situation may well be symmetrical, with the travelling one also seeing the Earthy one being younger.
Posted By: Revlgking Re: the mystery of time and light - 09/04/10 04:04 PM
Originally Posted By: Bill S.
Kallog....As far as the photon is concerned, I am not saying that "when it starts out it 'thinks' it's already at B"; I am saying that it is at A and B, in its own F of R, in a sort of infinite "present"....

"a sort of infinite present"? Pardon the intrusion. Sound's like what I have mind when, in the Not-Quite-Science section, I use the acronym 'G0D'

Earlier you wrote
Originally Posted By: Bill S.
Well done Socratus! You have brought us back, at least close to the point where Gan set things in motion.

With regard to your questions, I would suggest trying to think of time as a static entity, through which we are moving....
I agree. Interestingly Paul, in Acts 17:22-28, expresses the same concept of God--as the one in whom we live, move and exist.

http://www.biblegateway.com/passage/?search=Acts%2017:22-28&version=NLT

I prefer using the acronym. It helps me avoid thinking anthropomorphically--that is, thinking of a god in a human-like and limited form:

http://www.tnellen.com/cybereng/lit_terms/anthropomorphism.html
===========================
Posted By: Bill S. Re: the mystery of time and light - 09/04/10 06:38 PM
Revlgking: There is no intrusion - welcome to the thread. Have you read Julian Barbour's "The End of Time", Oxford 2000? He has an interesting take on the idea of static time.
Posted By: Bill S. Re: the mystery of time and light - 09/05/10 07:19 PM
After lots of thinking, and numerous cups of tea (which undoubtedly betrays my location as UK), I have come up with some thoughts I would like to share; i.e. have kicked around.

A photon is a quantum object. I suggest the use of Nick Herbert’s “quon” for a quantum object. (This definition found its way into Wikipedia yesterday.)

Quons are able to be in more than one place at a time, as long as they are not being observed. As far as I am aware, we have no evidence to indicate that the restriction to a single place, which we observe from our F of R, also applies in the F of R of the quon. In its own F of R it may still be everywhere at once. It may exist in infinity (=eternity).

Eternity is not an infinite expanse of time; in fact, it does not involve time, the two concepts are, incompatible. The concept of eternity as being in any way “temporal” arises from our limited ability to comprehend the nature of infinity. Like “Flatlanders” who cannot even imagine a third spatial dimension, we try to examine infinity using only our four dimensions of spacetime. Thus we find ourselves constantly falling back on temporal analogies and terminology, which are, at best, only of limited value, and, at worst, are downright unhelpful.

John Wheeler said that “Time is nature's way to keep everything from happening all at once”. This may sound like a flippant comment, but it is in fact quite a profound observation. We might say that eternity is the absence of time, and that in eternity everything must happen at once. However, even that statement is misleading: in order for something to happen there must be some passage of time. In eternity, everything just is.

Whatever one can do with mathematical infinities, it seems inescapable that any physical infinity must be immutable. The corollary of this is extremely important. An infinite cosmos cannot be multiplied nor divided. It can have nothing added to it, because there is nothing outside it that could be added. It can have nothing taken away, because to take something away would either make it less than infinite, or it would mean that there was something other than the all-embracing infinity, which would constitute a contradiction in terms.

If we were able to divide infinity, for example, by two, what would we be left with? One possibility seems to be that we would have two halves of infinity. Each half would be less than infinite, thus it would be measurable. Measure this quantity and multiply it by two and we have a measure of infinity, which is nonsense. The second possibility must be that each “half” somehow becomes infinite. Mathematically this seems reasonable; after all we can multiply or divide zero by any number we choose, and the outcome will be zero. Perhaps we also could do this, mathematically, with infinity, (Cantor almost certainly did), but practically there is the complication that anything that is truly infinity must contain everything; there cannot be two infinities, because each would have to contain the other.

This apparently intrinsic indivisibility of infinity leads one to wonder if any “part” of infinity can be distinct from any other “part”. Is it in any way meaningful to talk of parts of infinity? If it is not, and if our Universe is “part” of this infinite cosmos, then we seem to have a problem. However, the problem may not be as difficult to solve as it at first appears. Consider the following possibility. The cosmos is infinite; therefore every part of the cosmos is the whole cosmos. Everything, including our apparently finite Universe, is infinite. The birth of the Universe and perhaps its ultimate death exist together in infinity, along with all the things that seem to us to “happen” between those two points. It is all there, in eternity, in an all-embracing now. We perceive spatial differences, and the passage through time, because our minds need to make sense of the partial image to which we are restricted.

Consider events A, B and C. In linear time these might occur, one after the other, in that order. In eternity, though, they would all be present together. There could not have been a point in eternity when, for example, A had happened, but not B or C. The whole of eternity must contain A, B and C, in their entirety, for all eternity.

Just when you thought I had wandered infinitely far from the point, this brings us back to our photon travelling from A to B, via the Earth’s atmosphere. In our F of R there is a passage through time involved, but in the Photon’s F of R it is at A and B, and in the Earth’s atmosphere all at the same infinite point.
Posted By: Revlgking Re: the mystery of time and light - 09/05/10 10:49 PM
Bill S. IMO, this sounds like the "mind" that I am IN, when I think: GOD.

BTW, tell us how you feel about theology.
Posted By: kallog Re: the mystery of time and light - 09/06/10 12:17 PM
Originally Posted By: Bill S.

immutable. The corollary of this is extremely important. An infinite cosmos cannot be multiplied nor divided. It


What do you mean by cosmos? It seems you distinguish it from the universe which you describe as finite. Do you mean something 'outside' the universe? I think that's more of a psychological desire. Still, even the universe might turn out to be infinite, so all your comments can apply to that too.


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anything that is truly infinity must contain everything; there cannot be two infinities, because each would have to contain the other.


There isn't that requirement. For example how many integers are there? Infinitely many. Now how many real numbers are there? Also infinity. But yet the infinite set of integers is only a proper subset of the apparently larger and more inclusive set of real numbers. Mathematicians call these "countable infinity" and "uncountable infinity". I guess there are other ways to classify different types of infinities too.



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there is a passage through time involved, but in the Photon’s F of R it is at A and B, and in the Earth’s atmosphere all at the same infinite point.


If it slows in the Earth's atmosphere then it's <c, so it experiences passage of time, so it's not at A and B simultaneously.
Posted By: Bill S. Re: the mystery of time and light - 09/06/10 09:15 PM
Originally Posted By: Kallog
What do you mean by cosmos?


Perhaps it would help if I outlined the way in which I use a few terms. It might be good if others, who use these terms differently posted their versions as well.



1. Universe: following John Gribbin, this is what started with the Big Bang. It is what we observe around us, and what I believe is finite.

2. universe: this could be any member of a multiverse, or any theoretical universe that might be under discussion.

3. cosmos: anything, including our Universe or a multiverse which may, or may not extend beyond that which we can observe, detect or definitely prove to exist. Personally, I believe that it is the cosmos, within this definition, that is infinite.

4. infinite: that which is all-embracing, boundless and eternal. Nothing that exists can be separate from infinity, nor can anything that is at any point finite become infinite. Our Universe may be unbounded; it may continue to expand for ever, but it will never become infinite.

5. eternal: because we are constrained to think in 4-D terms, we find it necessary to impute to infinity a temporal facet. This distinction exists only in our limited perception.

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how many integers are there? Infinitely many.


I wondered who would be the one to raise this argument.

Up until the early nineteenth century, mathematical existence was rather similar to physical existence. Both were considered to exist in the real world. The discovery of non-Euclidean geometries changed that view. Mathematical ‘existence’ came to mean only logical self-consistency and this did not require physical existence to complete it. If mathematicians could write down sets of non-contradictory axioms, and formulate rules for deducing true statements from them, then those statements were held to ‘exist’. If there can be such a profound difference between physical and mathematical “existence”, or “truth” then it seems reasonable to identify a similar difference between physical and mathematical infinities. The infinite series is entirely a mathematical entity.

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If it slows in the Earth's atmosphere then it's <c, so it experiences passage of time,


Let us not forget that even when light is travelling at "c" we, in our F of R perceive a passage through time. Can we be sure that the apparent reduction of the speed of light in the Earth's atmosphere is not also a feature of our limited perception? Why should there be any change, of any sort, in the F of R of the photon?
Posted By: Revlgking Re: the mystery of time and light - 09/07/10 07:13 PM
Bill S., I think it was Carl Sagan--the astronomer and great popularizer of science-- who said of the cosmos: "The cosmos is all that is or ever will be."
I write more about this at:
http://www.wondercafe.ca/discussion/religion-and-faith/hawking-outs-god-creation

Meanwhile, it is great to read interesting dialogue without the silly comments from people who lack the ability to debate without personal attacks.
Posted By: kallog Re: the mystery of time and light - 09/08/10 02:46 AM
Originally Posted By: Bill S.

The cosmos is infinite; therefore every part of the cosmos is the whole cosmos. Everything, including our apparently finite Universe, is infinite.

4. infinite: that which is all-embracing, boundless and eternal. Nothing that exists can be separate from infinity, nor can anything that is at any point finite become infinite. Our Universe may be unbounded; it may continue to expand for ever, but it will never become infinite.


I think your first point must be wrong, because a finite part of an 'infinite' thing is not all-embracing, so it's not also infinite itself. You suggested you can't take a finite part, but I think you surely have to be allowed to. Why not? The leftover bits wouldn't be 'infinite' anymore by your definition, but they may still have infinite extent in the traditional meaning of the word.

I wonder if you're getting into some Zeno paradox??
Posted By: Bill S. Re: the mystery of time and light - 09/08/10 07:27 PM
Originally Posted By: Kallog
...a finite part of an 'infinite' thing is not all-embracing, so it's not also infinite itself.


You must be a mathematician, if not by profession, then certainly by inclination. Try to divorce yourself from Cantor and his infinity of infinities (countable and uncountable). Forget the infinite series, in its many guises. These things exist only in the minds of mathematicians. They have less affinity with reality than does the square root of minus one. (I know I am going to regret bringing the sqrt of -1 into it).

You are probably familiar with holographic plates. Not the holograms we find on credit cards etc.,but those which when viewed by reflected light just look like a lot of swirls, but which when viewed by the right sort of transmitted light produce 3D images.
You are probably aware that however many times you cut one of these plates in half (or any other fraction), it will still product the whole 3D image. The quality will diminish, but the entire image is still there. It seems that every part of the plate contains the whole image. Physical infinity must be rather like this. Every part is the whole.

A finite part of an infinite thing is a figment of the mathematician's imagination.
Posted By: kallog Re: the mystery of time and light - 09/08/10 11:07 PM
Originally Posted By: Bill S.

mathematicians. They have less affinity with reality than does the square root of minus one. (I know I am going to regret bringing the sqrt of -1 into it).

Hehe regret indeed. -1 itself has no more affinity with reality than sqrt(-1)

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still product the whole 3D image. The quality will diminish, but the entire image is still there. It seems that every part of the plate contains the whole image.


I've heard of that. But a diminished quality means it's not the whole image. Perhaps by "all embracing" you mean covers the complete range of space/etc, but may not actually include everything within that range?

The real world isn't all holographic plates, it includes some conventional photographic plates too. I still don't get what's wrong with a finite part of an infinite thing. Imagine the universe was infinite in extent. A single atom is surely a finite part of that, isn't it? Furthermore if there was a distinction we could know if the 'cosmos' was infinite or not simply by observing anything in it - oh look that atom is only finite, so the cosmos must be finite too. Or hey all these atoms are infinite, that means there's other stuff outside our finite universe.

I think it's a good idea not to invent new meanings for old terms. It seems you don't really mean "infinity". Perhaps just call it "all embracing" or something else to avoid confusion by people like me.
Posted By: Revlgking Re: the mystery of time and light - 09/09/10 12:40 PM
ABOUT THE RESEARCH OF Dr.Michael Persinger
==========================================
Dr. Persinger is a Neuoscientist at Laurentian U. who has been conducting experiments on 'god experiences' for the last few years. What he actually does is stimulate parts of the brain in his research participants in order to manufacture feelings of religious experience, alien abduction, encounters with ghosts etc. I believe his goal is to "prove" that religion and many other so called "mystical" or unexplained experience can be attributed to reactions in parts of the brain. )

(Just to self-identify, I am not an atheist myself, however, I have followed Persinger for awhile.)

Here is a bit from his bio/research interests at Laurentian:

"As a human being, I am concerned about the illusionary explanations for human consciousness and the future of human existence. Consequently after writing the Neuro-psychological Base of God Beliefs (1987), I began the systematic application of complex electromagnetic fields to discern the patterns that will induce experiences (sensed presence) that are attributed to the myriad of ego-alien intrusions which range from gods to aliens.

"The research is not to demean anyone's religious/mystical experience but instead to determine which portions of the brain or its electromagnetic patterns generate the experience. Two thousand years of philosophy have taught us that attempting to prove or disprove realities may never have discrete verbal (linguistic) solutions because of the limitation of this measurement.

"The research has been encouraged by the historical fact that most wars and group degradations are coupled implicitly to god beliefs and to the presumption that those who do not believe the same as the experiment are somehow less human and hence expendable. Although these egocentric propensities may have had adaptive significance, their utility for the species' future may be questionable."

To which I commented:

So what if Dr. Persinger's research helps us see how GOD does interpenetrate matter! As John tells us: "The Word became flesh ..." Unitheism welcomes such research. The important question is: How, with the help of the media, which loves to headline the bad news, are we going to get this good news out there? It could be of great value in helping us deal with the problem of evil in the human body, mind and heart (spirit), the root cause of so much pain and suffering.


====================
Reference:
http://www.wondercafe.ca/discussion/religion-and-faith/atheism-part-2-science#comment-508174
Posted By: redewenur Re: the mystery of time and light - 09/09/10 08:00 PM
You've veered off topic there, Rev. Another thread in NQS, maybe?

However -

"The research is not to demean anyone's religious/mystical experience but instead to determine which portions of the brain or its electromagnetic patterns generate the experience..."

- A commendably scientific endeavour.
Posted By: Bill S. Re: the mystery of time and light - 09/09/10 10:45 PM
Originally Posted By: Kallog
...oh look that atom is only finite, so the cosmos must be finite too. Or hey all these atoms are infinite, that means there's other stuff outside our finite universe.


Aha! We have a glimpse of that effervescence that bespeaks a delight in argument for its own sake.

The fact that we are restricted to the 4D of spacetime prevents us from making the sort of observations you suggest. If that were not the case we would all be able to observe, and understand, infinity, so this discussion would be unnecessary.

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…a diminished quality means it's not the whole image.


Of course, you are right, but an analogy is not the real thing, and should not be taken too literally. Possibly your "conventional photographic plates" should be regarded in this sense?

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I think it's a good idea not to invent new meanings for old terms.


I don’t think I have invented a new meaning for infinity. The Ancient Greeks and Augustine of Hippo, among others, were there centuries ahead of me. It was Cantor who introduced a new way of thinking about infinity when he let mathematicians loose on it. I am not saying that was a bad thing, only that it resulted in a lot of muddled thinking among those who did not distinguish between mathematical infinities and physical infinity.

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Perhaps just call it "all embracing" or something else to avoid confusion by people like me.


It is certainly not my intention to cause confusion, but I doubt that replacing “infinity” with “all embracing” would enhance clarity.
Posted By: kallog Re: the mystery of time and light - 09/10/10 03:55 AM
Originally Posted By: Bill S.

The fact that we are restricted to the 4D of spacetime prevents us from making the sort of observations you suggest.

Huh? We can see atoms, or Christmas cakes and notice that they're finite in space. So why not just look at them and say "oh the cosmos is finite because this part of it is also finite"?


Quote:

Of course, you are right, but an analogy is not the real thing, and should not be taken too literally. Possibly your

But that was the critical point of the idea! That a finite part still includes everything. A holographic plate doesn't do that, so the analogy isn't relevant.


Can you explain what your 'infinity' means?

I think you said "all embracing". That's certainly not what it means to most people. You're really not using the same definition, so nobody knows what you mean. I think if you call it "ugbugu" then you can't lean on people's preconceptions, and you'll be forced to really understand what it means in your context.


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I don’t think I have invented a new meaning for infinity. The Ancient Greeks and Augustine of Hippo

It doesn't matter what happened thousands of years ago. The meaning that it's generally given today seems to be very different from your meaning. That difference has allowed you to make some logical deductions which would fail if the conventional meaning of infinity were applied.
Posted By: Bill S. Re: the mystery of time and light - 09/10/10 12:11 PM
To "ugbugu" and beyond....!

Originally Posted By: Kallog
It doesn't matter what happened thousands of years ago
. I can't agree that we can discount all the milestones in science and maths, just because they occurred before we were around to argue with them.

Perhaps we need to clarify one point at a time. Let's start by finding out if you agree that a mathematical reality is not necessarily the same as a physical reality.
Posted By: kallog Re: the mystery of time and light - 09/10/10 03:31 PM
Originally Posted By: Bill S.
To "ugbugu" and beyond....!
:P

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I can't agree that we can discount all the milestones in science and maths, just because they occurred before we were around to argue with them.

I mean it doesn't matter to this discussion, just trying to stay focussed.


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by finding out if you agree that a mathematical reality is not necessarily the same as a physical reality.

Sure I agree.

Posted By: Bill S. Re: the mystery of time and light - 09/10/10 04:39 PM
Originally Posted By: Kallog
Sure I agree
.

Good. (2): Do you accept that a mathematical infinity is not necessarily the same thing as a physical infinity?
Posted By: kallog Re: the mystery of time and light - 09/11/10 02:53 AM
Originally Posted By: Bill S.
Originally Posted By: Kallog
Sure I agree
.

Good. (2): Do you accept that a mathematical infinity is not necessarily the same thing as a physical infinity?


I don't think there can be such a thing as a physical infinity. There might be a quantity which can be measured to have the value infinity, but that's only a mathematical representation of something else. For example how much time does it take for a stationary object to move 1m? Answer is infinity, is that a physical infinity? Another example. If the universe was infinite in extent, we could simply define its size as 1/extent. So it's size becomes 0 in our new units. The apparent physical infinity has just evaporated.

Would you say there's such a thing as a physical "3"? A physical "-3"? A physical pi? A physical complex number?

I would say certainly not to all of the above, with the possible exception of "3", but even then it's tenuous.
Posted By: Bill S. Re: the mystery of time and light - 09/11/10 05:42 PM
Originally Posted By: kallog
There might be a quantity which can be measured to have the value infinity, but that's only a mathematical representation of something else.


Thanks. I didn't expect you to make my point for me....and so eloquently! What is the "something else"?

I agree that there is not a physical "3" etc. These are just mathematical conventions that are frequently used to quantify physical objects.

Let's have another go at finding some common ground. Would you think there could ever have been a time when absolutely nothing existed?
Posted By: kallog Re: the mystery of time and light - 09/12/10 02:12 AM
Originally Posted By: Bill S.
Thanks. I didn't expect you to make my point for me....and so eloquently! What is the "something else"?

Glad we agree. So why have you used infinity to describe physical things rather than measurements of physical things? That confusion of terms is what lead to all this 'every part contains the whole' business.

Quote:

Let's have another go at finding some common ground. Would you think there could ever have been a time when absolutely nothing existed?


If you include no time in absolutely nothing, then no, by definition. But if you mean time without matter and space, well naively it sounds possible, but maybe those physicists have found some interdependency between them.
Posted By: Bill S. Re: the mystery of time and light - 09/12/10 04:30 PM
Originally Posted By: K
..why have you used infinity to describe physical things rather than measurements of physical things?


If you answer the question "What is the something else" you will have answered your question as well.

According to the BB theory, time was created with the Universe. Unless you believe that something existed prior to the BB, then "no time" must be included in "nothing"
Posted By: kallog Re: the mystery of time and light - 09/12/10 11:42 PM
Originally Posted By: Bill S.
[quote=K]..why have you used infinity to describe physical things rather than measurements of physical things?


If you answer the question "What is the something else" you will have answered your question as well.


What was the question again? And what's the answer?
Posted By: Bill S. Re: the mystery of time and light - 09/13/10 11:52 AM
Originally Posted By: K
..why have you used infinity to describe physical things rather than measurements of physical things?


If a physical thing exists that can be measured as being infinite, then "infinity" would be as appropriately applied to that thing as to the measurement. However, I still maintain that any "infinite thing" that can be measured is only a mathematical infinity.
Posted By: kallog Re: the mystery of time and light - 09/13/10 02:28 PM
Originally Posted By: Bill S.
If a physical thing exists that can be measured as being infinite, then "infinity" would be as appropriately applied to that thing as to the measurement. However, I still maintain that any "infinite thing" that can be measured is only a mathematical infinity.


Now I'm getting lost again. Please apply it to a stationary object taking infinite time to travel a small distance.
Posted By: Bill S. Re: the mystery of time and light - 09/13/10 05:02 PM
Originally Posted By: K
Now I'm getting lost again. Please apply it to a stationary object taking infinite time to travel a small distance.



I’ll try, since you asked so politely.

First, I should take issue with “infinite time”; it is another example of the ubiquitous infinite series which cannot exist outside mathematics. However, in the interest of mutual understanding, let’s not be pedantic.

You want to talk about a stationary object taking infinite time to travel a small distance. If the object is stationary, it does not move, even a small distance. Even if it could be given infinite time, it would have to stop being a stationary object in order to move.

Your turn to do some explaining here: How does a stationary object move while still remaining stationary?

Let me try a little harder to understand what you are asking me to do. Can you tell me when a progression of time becomes infinite? Surely, a little time > a long time > a very long time etc. At what point can you say “this is now infinite”? Only at that point could you say that the stationary object had been stationary for an "infinite time", and even then it would not have moved.

I'm trying, but it seems that to ask the impossible, one has only to make it seem possible, then ask it!
Posted By: kallog Re: the mystery of time and light - 09/14/10 12:16 AM
Originally Posted By: Bill S.
now infinite”? Only at that point could you say that the stationary object had been stationary for an "infinite time", and even then it would not have moved.


OK I'll improve it. An object is decellerating such that its position asymptotically approaches x=2m. How long does it take to reach 2m? Isn't that infinite time?

Doesn't matter if the universe can last that long. We can imagine it happens in a universe that lasts forever. Like, say the one we're in according to the idea that it continues expanding and never ends.
Posted By: Bill S. Re: the mystery of time and light - 09/14/10 01:46 AM
Kallog. Its 2.45am here. I'm going to sleep on this one before I attempt to answer it.
Posted By: Bill S. Re: the mystery of time and light - 09/14/10 03:40 PM
Originally Posted By: K
An object is decellerating such that its position asymptotically approaches x=2m. How long does it take to reach 2m? Isn't that infinite time?


Now you're trying to confuse me with technical stuff, that's "candy from a baby"...too easy to be any fun. However, learning trumps point scoring in the serious threads, in my book, so here goes.

Would I not be right to say that an asymptote is just a mathematical device which bears no more relevance to the real world than did Zeno's paradox. An asymptotic relationship involving deceleration breaks down at Planck's length and Planck's time, if not before. Mathematical infinity, yes; physical infinity, no.
Posted By: kallog Re: the mystery of time and light - 09/14/10 04:38 PM
Originally Posted By: Bill S.
Now you're trying to confuse me with technical
No

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involving deceleration breaks down at Planck's length and Planck's time, if not before. Mathematical infinity, yes; physical infinity, no.


Hmm well yea I suppose it wouldn't continue moving as the classical mathematical description says. But that means this whole infinity philosophy depends on QM and would have been impossible to consider 100 years ago. Seems strange for philosophical possibilites to change so fast.

Anyway, here's another way. Have a wave, say EM. Reduce its frequency all the way to zero. What happens to its wavelength or period?


By the way, we can cancel this whole discussion if you reckon an object moving 'backwards' at 3m/s doesn't have a physical velocity of -3m/s. Pretty much any measurable quantity can be measured in different ways to give different numbers representing the same thing. We could make up new units to give all sorts of numbers - even complex numbers to represent physical things.


Back to way back. If numbers aren't physical things then what did you mean about all that infinity business? It should all be invalid because there's no physical infinity, just as there's no physical -3.

I have a feeling you just invented a new concept which nothing is known to comply with, gave it some properties, called it 'infinity', then made some deductions based on all this made-up stuff, and using some assumptions, made a conclusion about the possibility of multiple universes.

Reminds me of the guy who builds his castle higher by taking bricks out of the bottom and putting them on the top wink
Posted By: Bill S. Re: the mystery of time and light - 09/14/10 06:39 PM
Originally Posted By: K
depends on QM and would have been impossible to consider 100 years ago


Same can be said for wave/particle duality etc. etc. What's your point here?

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Have a wave, say EM. Reduce its frequency all the way to zero. What happens to its wavelength or period?


Come back Zeno...all is forgiven. Have you un-quantised your EM radiation for the sake of argument?

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It should all be invalid because there's no physical infinity, just as there's no physical -3.


If there is no physical infinity, then presumably, when we talk of an infinite universe (cosmos, or whatever), all we are saying is that it is unbounded. So why not say that?
Posted By: Bill S. Re: the mystery of time and light - 10/03/10 01:23 PM
Originally Posted By: gan
we can breakthrough the constant of time ( that means we can travel past or future ) as well


It is sometimes interesting to look back to see where discussions like this started. An important point here seems to be the possibility (or otherwise) of time travel; with past-directed TT being particularly relevant in view of recent experimental results with the speed of light.

In the course of thinking about TT, I found myself going round in circles, so I took my wife's advice and wrote everything down. The following is something I wrote a couple of years ago, which seems relevant here.

Think about other people! This is not an exhortation to indulge in charitable thoughts, laudable as such a practice might be, it is, rather, an invitation to think about the people who would be left behind by someone who travelled through time. Suppose you were to travel back a hundred years, what would become of your family and friends? Indeed, what would become of all the people who were living on Earth at the time from which you departed? The simple answer is that they have not yet been born. This is true in your frame of reference, but what of theirs? Suppose for a moment that it was not you who frisked off into the past; suppose it was your friend, or your neighbour, or even someone you did not know. What would happen to you? Nothing, I suspect! Life for you would not change. If you go back in time, your family and friends have to get on with their lives without you. They do not cease to be – in their frame of reference – only in yours.

What does this tell us about the nature of time? Intuitively, we think of only the present as being present. We reason, like St Augustine, that the past no longer exists and the future has not yet happened, so only the present is real; but if you travel to the past, then the past becomes your present, while the present which you left behind still exists for those who did not travel with you. This must raise questions about how you could have gone to the past, if the past were not real, and how your loved ones could still be living in the future, when the future has not yet happened. It begins to look as though time, past, present and future, are all relative: as though time might be a static entity, of which we are able to experience only an “infinitesimal point” as we progress through it. If time really is static, and we are moving through it, then surely we have overcome the first hurdle in our quest for time travel. We are already travelling through time, all we have to do is find some way to change the direction or speed at which we travel. If that sounds easy – think again!
Posted By: gan Re: the mystery of time and light - 10/29/10 03:47 AM
really confuse.... is that possible to change the direction or speed at which we travel???
Posted By: KirbyGillis Re: the mystery of time and light - 10/29/10 04:16 PM
I think that we’re overlooking something here. One of the most fundamental and revered laws of physics is the conservation of mass. If one could travel back to Jan. 1, 1812; they would be injecting additional mass into the universe of 1812. This isn’t going to happen.

I am just as enamored by Sci-Fi lore as anyone else. The notion of time travel to the past is romantic, mysterious, paradoxical… Fortunately, we don’t have to worry about the safety of our grandfathers. The past is not changeable because the laws of physics prohibit it… lucky us.
Posted By: Bill S. Re: the mystery of time and light - 10/29/10 05:19 PM
Originally Posted By: gan
is that possible to change the direction or speed at which we travel???


Let’s start from the idea that we are all travelling through spacetime at the speed of light. Obviously, not everyone will agree with that, but I thing you will find it is supported by S R. This will mean that any change in our speed through space will influence our speed through time.

We cannot claim that we are stationary in any absolute sense, so we usually regard the Earth as being stationary, and measure our movement relative to that.

When stationary, relative to the Earth, I am travelling through spacetime at “c”.
If I hop into an aeroplane and travel at “v”, relative to the Earth, I am still travelling through spacetime at “c”, so I am travelling through time at “c” – “v”.
I am moving into the future, relative to people on Earth, albeit at a very tiny rate.

When stationary on Earth, my speed through space, relative to Earth, is “v” = 0.
There is no way I can give “v” a minus value, so I can neither increase my speed through time, nor travel back in time.

Having said all that, there are those who believe that it is possible to exploit closed time-like loops to travel back in time, but that’s another story.
Posted By: KirbyGillis Re: the mystery of time and light - 10/30/10 04:00 AM
Originally Posted By: Bill S.
Originally Posted By: gan
is that possible to change the direction or speed at which we travel???


Let&#146;s start from the idea that we are all travelling through spacetime at the speed of light. Obviously, not everyone will agree with that, but I thing you will find it is supported by S R. This will mean that any change in our speed through space will influence our speed through time.

We cannot claim that we are stationary in any absolute sense, so we usually regard the Earth as being stationary, and measure our movement relative to that.

When stationary, relative to the Earth, I am travelling through spacetime at &#147;c&#148;.
If I hop into an aeroplane and travel at &#147;v&#148;, relative to the Earth, I am still travelling through spacetime at &#147;c&#148;, so I am travelling through time at &#147;c&#148; &#150; &#147;v&#148;.
I am moving into the future, relative to people on Earth, albeit at a very tiny rate.

When stationary on Earth, my speed through space, relative to Earth, is &#147;v&#148; = 0.
There is no way I can give &#147;v&#148; a minus value, so I can neither increase my speed through time, nor travel back in time.

Having said all that, there are those who believe that it is possible to exploit closed time-like loops to travel back in time, but that&#146;s another story.



Interesting viewpoint (v0=c). In my mind, the only aspect that can belie that possibility is length contraction. Why would travel at a slower speed result in more length compaction? Now, if the “fabric” of space were traveling at c, I would expect that result. For reasons that I don’t want to get into, I have my doubts about either scenario (Earth at c or space at c). However, I have no doubt that Earth is at some fraction of c (to say the least).

None-the-less… an interesting viewpoint. I don’t think that this scenario can be ruled out 100% and therefore, we should remain mindful of the possibility.

I also believe that exchanging the roles of the “background” and “figure” is a valuable exercise that can result in enlightenment.

Do you subscribe to this as a possibility or as a probability? If the “singularity” was traveling through space at the speed of light; how would this be convenient?

Please keep in mind that I am not busting chops here...I already know that you have a large abstract capacity.
Posted By: Bill S. Re: the mystery of time and light - 10/30/10 02:21 PM
Originally Posted By: KG
The past is not changeable because the laws of physics prohibit it… lucky us.


Enter the multiverse! Personally, I think it doesn't provide an answer to the problems of past-directed time travel, but it certainly has a good try.
Posted By: magiimice Re: the mystery of time and light - 11/07/10 07:28 PM
Albert Ainstein predicted that if you travel faster than light, you will travel backwards in time, and shrink. But is that so shure? If you trawel in the speed of light you woud reash you destination (b) at the exact time the light from your destination woud reash you start possision (a) at the exact time. So if you were going faster than light, you woud come to b before the light from b woud come to a. So from a it woud lock that you (c) have traweled back in time, but from you c and b time woud be normal, cuse light is yout a picture of whats happened. So a million lightyears we have the time to trawel from a to b with c. Then, c and light (d) Woud be each fast, and be at a and b at the exact same time, if c traweled each constant as d. So then c woud be this fast -> and d woud be this fast <- . Each fast. But when c came to b, a woud need another 1 000 000 lightyears to see the light from your ship at b. But if c traweled twice as fast as d you woud be traweling --> also twice the speed of light. Then, you woud be at b 500 000 years before d vame to a. Then they woudent see you traweling, cuse you are traweling faster than light. So if you sent a signal when you reached b with the speed -> same 2 000 000 years, but with the speed --> it woud be 1 500 000 years, cuse light still woud be traweling each fast. So if e is speed, the formular woud be: c= -> d=<- e= c=--> d= <- e 1/4 ore somthing. I am not good at formulars, and this is youst my thought.
Posted By: magiimice Re: the mystery of time and light - 11/08/10 07:22 PM
I am wery awere of Einsteins prediction of that nothing can go faster than light. But we have to test it. dosent we?
That is the point of science.

Another formulation woud be this. Speed=S Destionation=B Startoftrawle=C Acserelaiton=A Gravity=G You=Y Light=L Year=U Infinitve=I

L/S=1 L/A=I G=0 L/A-B-A=2 000 000 U Y/S=1 Y/A=I G=0 Y/A-B-A=2 000 000

Here lightspeed is defined as 1. Something you shoud notice.
Lets analyce. Lightspeed=1 lightacseleration=Infinitive Gravity=zero, that means there is no gravitaytion to slow down anything, Light from A to B and then back to A, takes 2 000 000 years, thats means from A to B takes 1 000 000 years with the speed of light. In rest you trawel in the speed of light, youst the same. That mean if you trawel with speed of 2, gravity is 0 and acseleration infinitive, you woud trawle twice as fast as light, thats mean you coundt be detected at right spot cuse when light reached detector, you woud be 2 lightyears away from detector if light traweled one year. So you cudent be detected at great accuratcy before you have stopped. Also traweling to a area where light cames from the past when it reaches earth, dosent mean you are traweling backwards in time.
Posted By: Bill S. Re: the mystery of time and light - 11/14/10 02:41 PM
Magiimice, would I be right in thinking that your line of reasoning is that any apparent past-directed time travel would depend on the frame of reference of the observer? If so, that, surely, is what relativity is "all about".
KG is right, we cannot change the past, because every point is an immutable spacetime event, and even the act of going to a point in the past, unless we were there originally, constitutes a change.
There are those who argue that the multiverse gets us round that difficulty, but I suspect that even the multiverse would not really solve the problem.
Posted By: Farsight Re: the mystery of time and light - 11/18/10 01:19 AM
Hi guys. Ever heard of a stasis box?. Like time travel, it's science fiction, but conceptually it's just a glorified refrigerator, and it tells you something important about "time travel".

No motion occurs inside a stasis box, so when I put you inside one, electromagnetic phenomena don’t propagate. So you can’t see, you can’t hear, and you can’t even think. Hence when I open the door 5 years later, to you it’s like I opened the door just as soon as I closed it. As far as you're concerned, you “travelled” to the future. But you did this by not moving. It wasn't you moving, it was everything else.

Ergo if you travel to the future by not moving, you aren't really travelling forward through time, hence there's no way you can travel backwards in time. For that to happen everything else in the universe would have to be subject to negative motion. And there's no such thing as negative motion. Motion is motion. You can reduce a rate of motion to zero, but you can't keep on reducing it.
Posted By: Bill S. Re: the mystery of time and light - 11/18/10 10:28 PM
Being shut in the refrigerator for 5 years does not sound like my idea of fun.
However, it has a slightly more realistic feel to it than Richard Gott's suggestion for constructing a time machine, which starts:

“First, disassemble the planet Jupiter and use its material to construct around yourself an incredibly dense spherical shell whose diameter is just a bit larger than the critical diameter needed for the mass to collapse to a black hole (for a Jupiter-mass shell, that is a bit larger than 5.64 meters, roomy enough for you to sit inside).”

Perhaps high speed time travel is the best option after all.
Posted By: Farsight Re: the mystery of time and light - 11/20/10 06:22 PM
Have a look at the simple inference of time dilation. What actually happens when you move fast on a round trip through space is that all your macroscopic motion reduces local motion. If you could travel at 99.99999999% of the speed of light there's hardly any local motion left, so it's a bit like being in the "no motion" stasis box. But there are practical problem,s like you hit stuff. And it takes a lot of energy to accelerate then decelerate. The best practical way to "travel to the future" would be via cryogenics. After all, we can freeze embryos now, so one day we'll maybe be able to freeze and defrost adults.
Posted By: gan Re: the mystery of time and light - 12/14/10 07:19 AM
I want to ask that why SR say that actual time = dt-dx??? The twin paradox tell us that the traveler will have a longer time... but if minus dt than it will be shorter!!!! can anybody teach me???
Posted By: Anonymous Re: the mystery of time and light - 01/03/11 04:18 AM
If you were to go faster than the speed(approximately 300000 meters per second) you bend space and time(much like a worm hole) shirnk space infront of you and expand it out the otherend,
thus,taking you to a differnt part of the universe and a different point in time.
Posted By: Bill S. Re: the mystery of time and light - 01/03/11 02:45 PM
Hi, Astrophysisict, good to see a new poster.

I would be interested to see the theoretical stuff to back your idea up. The maths would have to be fairly simple for me to cope. smile

My own thoughts would be that if you could actually reach the speed of light, you would have no time dimension in which to travel, so you would be everywhere at once. No need for wormholes to take you to other places.
Posted By: magiimice Re: the mystery of time and light - 01/17/11 12:00 PM
A multiverse woud let us travel in time. Well not exsactly. Travelling in time is inpossible. What we sees as time traveling, is simply creating a new universe.
Posted By: Bill S. Re: the mystery of time and light - 01/17/11 07:25 PM
Originally Posted By: magiimice
Travelling in time is inpossible.


Do you mean that past-directed TT is impossible, or do you include forward-directed TT as well.
Posted By: gan Re: the mystery of time and light - 08/06/11 10:31 AM
but actually we are watching at past... Doesn't we? We watch at our com... the light need time to travel from the com to our eyes. What happened if we look at "now" but not history?
Posted By: Bill S. Re: the mystery of time and light - 08/06/11 11:14 AM
Hi Gan, long time no see. smile

You make the point that every thing we see is in the past because it takes a finite time for light to reach us. How can we look at now? Surely "now" is a concept that exists only in the mind of the thinker.

We percieve ourselves as existing in time because we have a view of our existance that is restricted to just 4 dimensions. "Now" may be our only link to infinity outside QM.
Posted By: Revlgking Re: the mystery of time and light - 08/06/11 10:28 PM
Bill S:

Intrigued by the thread, "The mystery of time and light", today, I went back and checked what we said to one another last August and September, 2010. I think the thread was started by Gan (tell us more about yourself, Gan). I went back, particularly, to page 3 of this thread.

I do not expect you to recall that this was when I first "intruded" in this thread. However, thanks for your welcome.

Today, I took the time to go back and read, carefully, the very interesting dialogue that we then had about space, time and the cosmos. I found your comments very interesting.

At the time, you spoke of time as a "static entity". Is this what you said? If so, I have two questions:

What is a "static entity"?

I also ask: Is space, for you, also a "static entity"?
Posted By: gan Re: the mystery of time and light - 08/07/11 01:52 AM
I'm just a normal student. And I don't think space is a static entity because I think that space is just a imaginative place. A place where start from nothing and end with nothing.

I used all over my holiday on reading String Theory, GR, SR and QM. I don't agree all of this. We just like an ant, start from an end to the other end. We will never reach the reality if we start like this.

Can you feel that if we start from one real thing, we will just get another real thing? It is wrong because we are just get things that start and end with a finite space. What if we think that all things through space are just imaginative, change when we change, static when we static?

It is just what I think. No offense.

________________________________________________________________
"Every moment of your life is infinitely creative and the Universe is endlessly bountiful. Just put forth a clear enough request, and everything your heart desires must come to you."
written by Shakti Gawain
Posted By: redewenur Re: the mystery of time and light - 08/07/11 10:42 AM
I think I understand what you're saying, gan, but please correct me if I don't:

You think that because science is limited to the study of the physical universe that the knowledge derived from it must be incomplete and therefore wrong.

I agree that one would be in error to suppose that science alone can ever provide a total picture of reality. As Erwin Schrödinger said...

"The sensation of colour cannot be accounted for by the physicist's objective picture of light-waves. Could the physiologist account for it, if he had fuller knowledge than he has of the processes in the retina and the nervous processes set up by them in the optical nerve bundles and in the brain? I do not think so."

Schrodinger was pointing out that the realities we experience, known to philosphers as 'qualia', are beyond the reach of science, even though all the associated physical phenomena may be precisely accounted for.

Is that what you mean? If so, 'incomplete' is true, and 'wrong' is true to that extent, in this context.

Scientific theories can, of course, be wrong or incomplete in other ways - and they most often are found to be incomplete. But the trend is quite evidently toward refinement and an ever greater working knowledge of the physical universe.
Posted By: Revlgking Re: the mystery of time and light - 08/07/11 02:07 PM
Originally Posted By: redewenur
.... As Erwin Schrödinger said...

"The sensation of colour cannot be accounted for by the physicist's objective picture of light-waves. Could the physiologist account for it, if he had fuller knowledge than he has of the processes in the retina and the nervous processes set up by them in the optical nerve bundles and in the brain? I do not think so."

Schrodinger was pointing out that the realities we experience, known to philosphers as 'qualia', are beyond the reach of science, even though all the associated physical phenomena may be precisely accounted for.

Is that what you mean? If so, 'incomplete' is true, and 'wrong' is true to that extent, in this context.

Scientific theories can, of course, be wrong or incomplete in other ways - and they most often are found to be incomplete. But the trend is quite evidently toward refinement and an ever greater working knowledge of the physical universe.
Rede..., thanks for pointing this out to us. To help clarify things may I add the following ABOUT Qualia (From which we probably get our word 'quality')
First published Wed Aug 20, 1997; substantive revision Tue Jul 31, 2007

Feelings and experiences vary widely. For example, I run my fingers over sandpaper, smell a skunk, feel a sharp pain in my finger, seem to see bright purple, become extremely angry. In each of these cases, I am the subject of a mental state with a very distinctive subjective character.

There is something it is like for me to undergo each state, some phenomenology that it has. Philosophers often use the term ‘qualia’ (singular ‘quale’) to refer to the introspectively accessible, phenomenal aspects of our mental lives. In this standard, broad sense of the term, it is difficult to deny that there are qualia.

Disagreement typically centers on which mental states have qualia, whether qualia are intrinsic qualities of their bearers, and how qualia relate to the physical world both inside and outside the head.

The status of qualia is hotly debated in philosophy largely because it is central to a proper understanding of the nature of consciousness. Qualia are at the very heart of the mind-body problem.

http://plato.stanford.edu/entries/qualia/
Posted By: Bill S. Re: the mystery of time and light - 08/07/11 06:52 PM
Rev, I, too, went back to page 3 to remind myself of the context in which I talked of time as a "static entity". I am bringing the appropriate paragraph into this post so as not to have to keep going to and fro.

"With regard to your questions, I would suggest trying to think of time as a static entity, through which we are moving. In that way, time does not have to change from being “frozen” to being variable, any more than space has to change when we start to move about.
Only in the frame of reference of an observer does time appear to change. True, relativity tells us that an observer in motion relative to something else can with equal validity consider herself to be moving, or the “something else” to be moving, but in the case where the “something else” is time that may make no more sense than Einstein’s alleged question: “Does Oxford stop at this train?”"

By a "static entity" I mean nothing more than an indeterminate thing that does not have movement as an essential, diagnostic feature. I was not stating definatively that time, even in my opinion, is a static entity; just suggesting thinking of it that way as a thought experiment.

Obviously, one could apply the same thought experiment to space.

OK. Now I have done what so often happens in discussions like this: I have answered both your questions without actually answering either. smile

This is probably as near as I can get to a straight answer: In the present state of my knowledge/understanding, static time makes more sense to me than flowing time. I suspect the same may be true of space, but relativity casts some doubt on that.
Posted By: Revlgking Re: the mystery of time and light - 08/07/11 10:39 PM
BS--I admit I am a joker--perhaps I will stick with, Bill S. smile

Meanwhile, I see you respond with a confession
Quote:
OK. Now I have done what so often happens in discussions like this: I have answered both your questions without actually answering either. smile
Your response being as you describe it to be, prompts me to ask the following questions: Do you have a problem with the questions I asked? If so, how could I have worded my questions to avoid problems?

Is there such a thing as an objectionable--maybe even stupid--question? BTW, I just found this:

http://www.wired.com/wiredscience/2010/02/what-is-time/

Me? I have always thought of time as somewhat GOD-like. It is something in which I live, move and have my being.
Posted By: Orac Re: the mystery of time and light - 08/08/11 05:39 AM
There are a number of views lets look at them.

GR Perspective:

From a modern science GR perspective space and time can't be seperated to do so will lead you to anomolies the correct term from Einstein perspective is to talk about spacetime. It is a loaf of bread which exists here and now for all space and all time how you slice it sections your view. It begins at some inflationary point and ends ???? we dont know.

Conceptually the problem becomes that of freedom of choice if all space and all time is already defined then all fate is set in stone.


Enter Quantum mechanics:

Quantum mechanics exists only in time space does not exist for it. You entangle two particles does not matter how far you seperate them they will respond because QM works in a world without space.

Modern thinking is this is important because light has a Quantum side to it even though GR specifies that spacetime exists QM will tell you the nature of light can be changed as required across the spacetime loaf. Thus QM ensure freedom of choice even though the fabric is set. Wheeler's delayed choice quantum erasure experiment done on photons leaving a star billions of years ago means an observation now can reach back billions of years which if you think about it is astounding (http://www.bottomlayer.com/bottom/basic_delayed_choice.htm).


Our Personal view:

As a number of people above commented we don't see the world as science does we see it as sensory input. The world is definitely a solid 3D construct and time progresses from second to second and we know what is behind us but not what is infront.


If you notice all three views are at odds with each other and that in a nutshell is why there is problems.

For revlgking where does GOD fit in ... wherever a person wants it to fit in. Science is about study of physical observation and facts and if a divine body exists they can make and break whatever science they want. Hence religion lies outside science as even our personal view is somewhat outside science which is causing us so much angst.
Posted By: Bill Re: the mystery of time and light - 08/08/11 01:55 PM
Originally Posted By: Orac

If you notice all three views are at odds with each other and that in a nutshell is why there is problems.

That is a better way to say it than I have been using. Thanks

Originally Posted By: Orac
For revlgking where does GOD fit in ... wherever a person wants it to fit in. Science is about study of physical observation and facts and if a divine body exists they can make and break whatever science they want. Hence religion lies outside science as even our personal view is somewhat outside science which is causing us so much angst.

Another well stated summation of the problem.

Bill Gill
Posted By: Revlgking Re: the mystery of time and light - 08/08/11 09:55 PM
Interesting and stimulating response, Orac.

Assuming you are a physicist, I will interject some comments of my own, in [brackets] and within your comments:

Originally Posted By: Orac
There are a number of views lets look at them. GR [By using GR, I assume you mean general relativity, right?] Perspective:

From a modern science and GR--general relative--perspective, space and time can't be separated [This, in my opinion, is a GOD-like quale, or quality. See: http://en.wikipedia.org/wiki/Qualia] to do so will lead you to anomalies. [Note: I put a period.] The correct term from Einstein perspective is to talk about spacetime.

[Orac, Einstein was, in my opinion, a unitheist. So was Spinoza.

A unitheist (I put this word in Wikipedia), or panentheist (also see Wikipedia).

What is clear is this. Neither Spinoza nor Einstein thought of 'god' as an objective being--a 'god' with dimensions.

A 'god' with dimensions is an idol, a work of art, which can be a symbol for good, or evil. To get beyond this limited and simplistic way of thinking is why I use the acronym, GOD, not the noun, God.

By the way, Orac, I assume that you are a physicist.

As such do you acknowledge that there is more to existence than that which we call measurable material? Do you give much thought to philosophy, to theology and the like?
You go on
]:

It is a loaf of bread which exists here and now for all space and all time how you slice it sections your view.

[OK, by saying this, it seems to me that you think and feel, as do I: We are human (spiritual) beings who are continuously creating the reality we have. If so, what a wonderful opportunity there is for us to create what we will have--the future. If this is so, this means that each of us is a GOD-like son or daughter of GOD. Meaning no disrespect to well-trained dogs I add:If we want to be DOG-like beings (dominating, diabolic, over-bearing and growling grinch-like beings we are free to make that choice..

Of course, we are also free--within the laws of nature--to destroy the earth and turn it into the kind of jungle--ruled by the laws of the jungle--that perhaps it was billions of years ago, especially when it was what scientists call pangea--long before the time of air-breathing land creatures. See: http://en.wikipedia.org/wiki/Pangaea

Or--again within the laws of nature as we understand them--it could over time--much time of course--become more and more of a mixture of jungle and desert--one unfriendly to air-breathing creatures like us.

THE OPTION I CHOOSE
Or, we also have the option to make it into, not only "a thing of beauty and a joy forever" (Keats) but a beautiful space-ship earth from which our descendants will continue to explore the planets and beyond. When my wife and I were both 39 (1969) we had the privilege of seeing the live TV broadcast of the moon-landing when the astronautic, Neil Armstrong took that first giant step for humanity
]

It begins at some inflationary point and ends ???? we don't know.

Conceptually the problem becomes that of freedom of choice if all space and all time is already defined then all fate is set in stone.

Enter Quantum mechanics:

Quantum mechanics exists only in time space does not exist for it. You entangle two particles does not matter how far you separate them they will respond because QM works in a world without space.

Modern thinking is: this is important because light has a Quantum side to it even though GR specifies that spacetime exists QM will tell you the nature of light can be changed as required across the spacetime loaf. Thus QM ensure freedom of choice even though the fabric is set. Wheeler's delayed choice quantum erasure experiment done on photons leaving a star billions of years ago means an observation now can reach back billions of years which if you think about it is astounding (http://www.bottomlayer.com/bottom/basic_delayed_choice.htm).

"Our Personal view [Do you mean your personal view?] :

As a number of people above commented we don't see the world as science does we see it as sensory input.

The world is definitely a solid 3D construct and time progresses from second to second and we know what is behind us but not what is in front.

If you notice all three views are at odds with each other and that in a nutshell is why there is problems.

For revlgking where does GOD fit in ... wherever a person wants it to fit in. Science is about the study of physical observation and facts and if a divine body exists they can make and break whatever science they want.

Hence religion lies outside science as even our personal view is somewhat outside science which is causing us so much angst.
Posted By: Bill S. Re: the mystery of time and light - 08/09/11 01:45 AM
Originally Posted By: Rev
Do you have a problem with the questions I asked? If so, how could I have worded my questions to avoid problems?


I have no problem with your questions, which is why I answered them. However, I thought it appropriate to point out that your questions seemed to imply that I had made a statement that I had not made. Far be it from me to neglect an invitation to a little verbal sparring. smile
Posted By: Orac Re: the mystery of time and light - 08/09/11 03:05 AM
Originally Posted By: Revlgking

They never thought of 'god' as an objective being--one with dimensions. A 'god' with dimensions is an idol, a work of art, which can be a symbol for good, or evil. To get beyond this limited and simplistic way of thinking is why I use the acronym, GOD, not the noun, God.


And that is entirely possible our universe appears to be a construct and there does appear to be things outside it which I would believe is the current mainstream view.

If you like I am telling you explicitly Big bang nor any other physics can deny the existance of god because our world is not as hard and set as our human mind percieves and that is the personal view I was talking about.

It is only layman understanding that pits Big bang against God because the layman thinks the Big Bang is the start as a physicist it's just an event just like our sun will blow up one day.

Hmmmm ... never thought about that I guess layman would consider that the end of the universe because there world ends which of coarse it is not from a physics point of view the universe would tick along quite happily without our solar system.
Posted By: Revlgking Re: the mystery of time and light - 08/09/11 05:00 PM
Originally Posted By: Bill G
...
Originally Posted By: Orac
For revlgking where does GOD fit in ... wherever a person wants it to fit in.

Science is about study of physical observation and facts and if a divine body exists they can make and break whatever science they want. Hence religion lies outside science as even our personal view is somewhat outside science which is causing us so much angst.
Another well stated summation of the problem. Bill Gill
Bill G, I suspect that when Orac says--and correct me if I am wrong, Orac--that religion, which is a very person-based phenomenon, and our personal opinions are somewhat outside science, he does not mean that they must be enemies of one another. All he is doing is stating it as a fact. I think that the way we personally perceive what is going on, physically, is a challenging and interesting problem--one looking for a solution. Working on and finding a solution could help us have to less angst.

Orac--again I say, correct me if I am wrong--as an example of what it means to have a personal point of view, here is how I heard what you said to me. Here is my personal perception, in my words + your words, of your recent post:
Quote:
It is entirely possible that our universe is a construct, and there does appear to be things--beyond our current ability to detect--outside it, which I would believe is the current mainstream view.

I hear you say: I am telling you explicitly: Neither the Big bang, nor any other phenomenon of physics, can neither deny, nor affirm, the existence of god.

Why do I say this? because our world is not as hard-wired and set as our human mind perceives. Personally speaking, that is what I was talking about.

PROFESSIONAL OPINIONS--are valuable, but can differ
EXPERT OPINIONS--again, valuable, but can differ
LAY OPINIONS--same as the above
COMMONSENSE OPINIONS--not always held in common
LAWS--are opinions codified
ABOVE ALL--misunderstanding and miscommunication--can happen in all categories, and can lead to serious conflict.

Interestingly, our word 'laity' comes from the Greek word, laos. It means the people, the mob, the crowd, the community in general).

For example, professional astro-physicists accept the Big-bang phenomenon of the creation of the universe, as we know it, as a confirmed theory. Lay people--often armed with ignorance--who know little about science and theology, will often jump to the conclusion that all scientists reject the value of religion and vice versa. Not true. As in all fields, wise people usually, and with an agape-based attitude, leave their options open.

Few educated religionists believe that there is a one true 'god'--like the one we read about in the first two chapters of Genesis--one who created the universe, as we know it, in six literal days, and rested on the seventh. Again, some do, and some don't. There is no such thing as one true theology. As the following quote makes clear, there is great flexibility, especially among those well-educated in the Bible as literature, in science and in theology.
Quote:
The Big Bang hypothesis is widely known in popular thought as the best explanation for how the universe came to be.

However, very few people know that a Catholic Christian priest formulated this theory in the late 1920s. Reverend Monsignor Georges Lemaître, a Belgian scientist, challenged the conventional thinking of his colleagues, including Albert Einstein, and rejected the static universe hypothesis for a dynamic model. In the course of carrying out his research, he confronted illogical thinking that pitted faith against reason, and science against the Church. His legacy extends beyond cosmology, to the nature of truth itself.
You see, the BIG Bang theory was actually proposed by a Christian priest--Father Georges Lemaitre http://www.catholicculture.org/culture/library/view.cfm?recnum=8847 Read more of his story in Wikipedia.

THE HISTORY OF SCIENCE--Of course there were and are atheist and agnostic thinkers, but the history of religion is also replete with the stories of great religionist thinkers from all faiths--Jewish, the great Eastern Religions, Christians, Muslims and others, who contributed--and are still doing so--so much to the growing body of knowledge (our philosophies, sciences and the arts) on which we base the laws of by which we live day to day.
Orac, you conclude your post with comments about the Big Bang and future of our Sun and its children, the
Planets: In reality, it was just an another event in space. just like
Quote:
our sun will blow up one day.

Hmmmm ... never thought about it that way before. I guess that for layman that would be the end of the universe, because the world as they know it would end. But from point of view of professional physicists the universe, as a whole, would go ticking along quite happily without our puny little solar system.
Posted By: Orac Re: the mystery of time and light - 08/10/11 03:26 AM
Correct revlgking I am happy with that.

Reality is very personal like religion physics is far starker than that ... and I am not sure stark is the right word.

The best I can use is Plato's and socrates cave story (http://en.wikipedia.org/wiki/Allegory_of_the_Cave)

Quote:

In the dialogue, Socrates describes a group of people who have lived chained to the wall of a cave all of their lives, facing a blank wall. The people watch shadows projected on the wall by things passing in front of a fire behind them, and begin to ascribe forms to these shadows. According to Socrates, the shadows are as close as the prisoners get to viewing reality. He then explains how the philosopher is like a prisoner who is freed from the cave and comes to understand that the shadows on the wall do not make up reality at all, as he can perceive the true form of reality rather than the mere shadows seen by the prisoners.


Reality is defined by what one senses not by the reality of physics.
Posted By: Revlgking Re: the mystery of time and light - 08/11/11 03:54 AM
Stark? Did you mean "rigid" ?

http://www.merriam-webster.com/dictionary/stark?show=0&t=1313033761

Which poses all kinds of questions like: Is reality an absolute? Or is it something which each individual creates for itself?

Do human beings (conscious and otherwise), animal beings, insects, vegetables, whatever all experience the same reality?
Posted By: Orac Re: the mystery of time and light - 08/11/11 07:08 AM
Originally Posted By: Revlgking


Yes thats better sorry I struggle with english :-)

Originally Posted By: Revlgking

Which poses all kinds of questions like: Is reality an absolute? Or is it something which each individual creates for itself?


QM answers that definitely via a law called Bell's Inequality (http://en.wikipedia.org/wiki/Bell's_theorem)

Quote:

The violations of Bell's inequalities, due to quantum entanglement, just provide the definite demonstration of something that was already strongly suspected, that quantum physics cannot be represented by any version of the classical picture of physics.


Many who believe in a one real physical world interpretation like Einstein were horrified by this and science has spent nearly 100 years trying to fight it.

We usually call our two observers Alice and Bob (A & B I know novel) and QM will proove they never experience the same reality it's not possible for them to unless there are hidden variables behind the scenes which we can show don't exist again via classic test that is EPR (http://en.wikipedia.org/wiki/EPR_paradox). This may be simpler to understand (http://www.science20.com/alpha_meme/why_...ould_have-81602)

Quote:

Einstein struggled to the end of his life for a theory that could better comply with causality, protesting against the view that there exists no objective physical reality other than that which is revealed through measurement interpreted in terms of quantum mechanical formalism.


Einstein really disliked QM :-)

I must admit when I first moved from GR to QM studies it was hard but it grows on you. It's not that it's really mind blowing just different to how you experience the world.

Originally Posted By: Revlgking

Do human beings (conscious and otherwise), animal beings, insects, vegetables, whatever all experience the same reality?


For the same reasons above no two humans would experience the same "physics reality".

I would say animals etc even more so because there sensory inputs are so different for example they can hear much higher up the audio spectrum.

Reality seems to be about the observer much more than the world is one of the main things QM teaches us.
Posted By: Bill Re: the mystery of time and light - 08/11/11 02:00 PM
Originally Posted By: Orac
Einstein really disliked QM :-)

Very true, which is especially strange when you consider that he was one of the pioneers of QM. One of the first stages of the development of QM was his explanation of the photoelectric effect, which is what he got his Nobel Prize for. And of course he was one of the main contributors to the EPR (Einstein–Podolsky–Rosen) paper about quantum entanglement (he didn't really believe in it) but it is one of the most quoted papers about entanglement.

Bill Gill
Posted By: Revlgking Re: the mystery of time and light - 08/11/11 08:42 PM
Originally Posted By: Bill
Originally Posted By: Orac
Einstein really disliked QM :-)
... And of course he was one of the main contributors to the EPR (Einstein–Podolsky–Rosen) paper about quantum entanglement (he didn't really believe in it) but it is one of the most quoted papers about entanglement. Bill Gill
BG: Does the following, from The Stanford Encyclopedia of Philosophy, mean that some modern physicists are actually catching up to what some philosophers, theologians and pneumatologists have been saying all along? In Hamlet (Act 1, scene V) Shakespeare puts the following words in the mouth of Hamlet: There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.

http://plato.stanford.edu/entries/qt-entangle/

Quote:
2. Exploiting Entanglement: Quantum Teleportation: Quantum Teleportation
Consider again Schrödinger's realization that an entangled state could be used to steer a distant particle into one of a set of states, with a certain probability. In fact, this possibility of ‘remote steering’ is even more dramatic than Schrödinger demonstrated.

Suppose Alice and Bob share an entangled state of the sort considered by Bell, say two photons in an entangled state of polarization. That is, Alice has in her possession one of the entangled photons, and Bob the other. Suppose that Alice has an additional photon in an unknown state of polarization |u>, where the notation ‘|&#8201;>’ denotes a quantum state.

It is possible for Alice to perform an operation on the two photons in her possession that will transform Bob's photon into one of four states, depending on the four possible (random) outcomes of Alice's operation: either the state |u>, or a state that is related to |u> in a definite way. Alice's operation entangles the two photons in her possession, and disentangles Bob's photon, steering it into a state |u*>.

After Alice communicates the outcome of her operation to Bob, Bob knows either that |u*> = |u>, or how to transform |u*> to |u> by a local operation. This phenomenon is known as ‘quantum teleportation.’

What is extraordinary about this phenomenon is that Alice and Bob have managed to use their shared entangled state as a quantum communication channel to destroy the state |u> of a photon in Alice's part of the universe and recreate it in Bob's part of the universe.
Posted By: Bill S. Re: the mystery of time and light - 08/11/11 09:34 PM
Quote:
What is extraordinary about this phenomenon is that Alice and Bob have managed to use their shared entangled state as a quantum communication channel to destroy the state |u> of a photon in Alice's part of the universe and recreate it in Bob's part of the universe.


However, since neither Alice nor Bob could know this until they were able to communicate conventionally, this rather fanciful pseudo-teleportation, is of somewhat limited value.
Posted By: Revlgking Re: the mystery of time and light - 08/12/11 03:45 AM
Originally Posted By: Bill S.
... However, since neither Alice nor Bob could know this until they were able to communicate conventionally, this rather fanciful pseudo-teleportation, is of somewhat limited value.
What intrigues me in all this is the fact that serious intellects like the physicist, like David Bohm--I once heard him speak at the University of Toronto--and others are even giving serious thought to such ideas.

Note: This Page
http://technovate.org/web/articles/quantumthought.html
Quote:
It covers many interesting topics in physics and metaphysics and contains many interesting hyperlinks to other fascinating pages. So that you won't lose your place in this narrative, links on this page will open up to a new window on your web browser - leaving this original page still intact.

"Quantum Teleportation to Quantum Thought:
Psychism is now real Science"
by Ray White

Something very exciting has happened for the future of the unification of science and metaphysics. This new evidence I think is the greatest step forward towards a scientific realization that there might be some possibility for the existence of psychism, magic and miracles. That neat little thing, which hasn't gotten nearly enough fanfares in the press, is Quantum Teleportation.

Quantum Teleportation is a somewhat mindboggling concept, but it's really not all that hard to explain philosophically. The mathematics is mind-bendingly complex and I certainly don't fully understand it myself. However I have been doing much armchair physics research myself in the topic of quantum physics lately, and I would like to share some of that with you.

I will go into much more detail on this issue of Quantum Teleportation, and also several other physics theories that lead up to it and also strengthen the footing of metaphysics, magic, and miracles. Although for now let me just tantalize you.

Quantum Teleportation does something very unique in the annals of science. It shows that it is possible for one thing to effect another without any intervening mechanism involved...
Posted By: Orac Re: the mystery of time and light - 08/12/11 04:22 AM
And this one will make your day Revlgking

If we define a persons soul as an energy
http://www.technologyreview.com/blog/arxiv/24759/

We can transport energy across time and space.

Quote:

There is a growing sense that the properties of the universe are best described not by the laws that govern matter but by the laws that govern information. This appears to be true for the quantum world, is certainly true for special relativity, and is currently being explored for general relativity. Having a way to handle energy on the same footing may help to draw these diverse strands together.


Einstein would have been very unhappy but perhaps science is coming back more in favour with religion because the big bang is certainly not the start and end of the story.

So in some ways religion has been a bit harsh on science which simply follows the truth wherever it leads and however uncomfortable it gets.

And finally I thought I would share a thought experiment that shows just how funny reality is (http://www.newscientist.com/article/mg21128253.700-time-need-not-end-in-the-multiverse.html) ... see even 50/50 odds may not be what they seem.
Posted By: gan Re: the mystery of time and light - 08/12/11 12:02 PM
I think Einstein said that if our sun burnt out, our space-time will have a big wave. The wave is exactly the speed of light, and push our earth out from its path.

He said that if sun burnt out, we will saw lights, but is history of lights. Am I right?
Posted By: Bill S. Re: the mystery of time and light - 08/12/11 12:09 PM
“The essence of the argument is that you don't need any new information, in this case the fact that you woke up, to understand why the odds are no longer 50/50. In a multiverse that grows exponentially, where each new generation of universes is far larger than the last, younger universes always outnumber older ones. Waking up, you will either be in a universe in which 1 minute has passed (heads), or in a universe in which 1 hour has passed (tails). "The experiment sets up a 59-minute ambiguity in the age of the universe," Guth says. "You should always bet on the younger one."”

This seems logical, but unless you have changed universes while sleeping, you will still be in a universe in which the original odds were 50/50.
Posted By: redewenur Re: the mystery of time and light - 08/12/11 02:11 PM
Gan

According to Einstein's theory, the Earth is following a geodesic through spacetime that's curved due to the proximity of the sun's mass. See: http://oh-math.net/1.php

As far as I know, Einstein didn't actually refer to the sun burning out, but his theory says that if the sun suddenly ceased to exist then there would, in a sense, be a wave. This is because the spacetime curvature that the sun had caused would gradually disappear, beginning at the sun's former location, and spreading outward at the speed of light. The result would be that the Earth would, after about 8 minutes, begin to travel at a tangent to its former orbit. It would not have been pushed, and its momentum would be unchanged, but it would be following a new geodesic.

Regarding light, photons that left the sun during the final 8 minutes of its life would still be arriving at Earth for 8 minutes after it ceased to exist.

http://oh-math.net/1.php
http://www.physicsoftheuniverse.com/topics_relativity_curved.html
Posted By: Revlgking Re: the mystery of time and light - 08/12/11 09:00 PM
Originally Posted By: Orac
And this one will make your day, Revlgking
More than that, Orac: It also made my night laugh
BTW, is Orac your official name? Or is it the one you use here? And, what is your mother-tongue? Religion? Feel free not to tell us. Also, feel free to tell me: Mind your own business!

Being a lover of knowledge, I am just very curious about what makes people tick.

You go on:
Quote:
If we define a person's soul as an energy
http://www.technologyreview.com/blog/arxiv/24759/
We can transport energy across time and space.
You go on to say that science is coming back to the ideas of religion.

Orac, you mention soul "as an energy". Why not? Sounds like a good idea, to me.

Interestingly, for a logo, the Israeli airlines uses ELAL. EL comes from Hebrew. It is the root word for "the power, the energy" and also 'god'. The logo means "to the highest heights" (Genesis 1:1). AL is the root word in Arabic. ALLAH simply means, the one and only power.

MY IDEA OF RELIGION?
In my opinion, choosing to be bright, intelligent, moral, ethical, truth-loving, gentle, perceptive and people-serving scientists--ones who are not just interested in having power, fame and fortune--past and present, have been, and are, religious, in the best sense of the word. The same is true for positive religionists.

As a positive religionist, I have no right to demand that you trust me, just because I am ordained and ask you to trust me. It is up to me to win that trust by what I do. This was the basic message of Jesus: He never demanded that people give him blind obedience to "me and my church". He simply said--and I paraphrase--: Do to, and for, others--and expect them to do same in return--that which is moral, ethical and love-based.

PHILOSOPHY, RELIGION, SCIENCE, ART, POWER AND MONEY
Powerful words. As I understand them: philosophy, religion, science (ABOUT knowledge), religion (ABOUT wisdom--the use or abuse of knowledge), art (the application of knowledge), power (physical, mental and spiritual), and money are just servant-like tools.

In the hands of genuine, good-hearted and generous people--who I, as a religionist, call GOD-like people--such servant-like tools ought to be used to build of republics of GOD--ones ruled by secular laws, in which philosophy, religion, science, art, power and money are just that: servant-like tools--not dogmatic powers.

Even the best of powerful tools--for example, money--in the hands of disingenuous (insincere) mean-spirited, self-centered and greedy people will give us nothing but corrupt financial systems--Our media is full of such bad news in North America. How about Australia?--which are fear and greed-based. Such systems do not serve the common good.

Instead, they bring us famines that kill millions, and wars (usually started by criminal minds out for profit and power); dysfunctional families, riots in the streets, you know the story. You mention
Quote:
So, in some ways religion has been a bit harsh on science, which simply follows the truth wherever it leads and however uncomfortable it gets.
Religion harsh? Perhaps you mean, critical--like parents often are of their children. Religion, as I practice it, is never harsh--cruel, severe and without pity. I only speak out to be helpful and warn of dangers to come? Is that harsh?

BRIDGES BETWEEN SCIENCE AND RELIGION ARE EVEN NOW BEING BUILT
BTW, how many scientists are aware that there are a number of modern clergy who are also qualified scientists?
http://www.ordainedscientists.org/

In history, there were any number of ordained scientists. Just to name a very important few:
Copernicus, a monk. He was not just an astronomer:
http://en.wikipedia.org/wiki/Nicolaus_Copernicus
And who has not heard of Gregor Mendel
http://en.wikipedia.org/wiki/Gregor_Mendel

There also lay Christian scientists:
Galileo
http://en.wikipedia.org/wiki/Galileo_Galilei
Isaac Newton was a lay Christian--another man of many talents.
http://en.wikipedia.org/wiki/Isaac_Newton
Speaking of physics, there was
http://en.wikipedia.org/wiki/Max_Planck
He was a German and Lutheran layman.

By the way, I certainly agree with you when you say
Quote:
There is a growing sense that the properties of the universe are best described not by the laws that govern matter but by the laws that govern information.

This appears to be true for the quantum world, is certainly true for special relativity, and is currently being explored for general relativity. Having a way to handle energy on the same footing may help to draw these diverse strands together.

Interesting stuff. There's no telling where this kind of thinking might lead.

Posted By: Orac Re: the mystery of time and light - 08/13/11 02:56 AM
Orac was a fictional computer in the TV series Blake's 7. To me it was a milestone in thoughts about computers and there relationship to humans because Orac was not the slave computer that obeyed humans nor was it the crazed computer out of control like HAL 9000 in a space odyssey. It was basically a box that knew pretty much everything but had this rather caustic personality and would even refuse to answer question that were to stupid. It was an interesting thing here was this box that could pretty much solve everything but chose not to out of ego, indifference and dislike for the stupid humans.

Nationality Tatar, from Uzbekistan, from the former USSR and there is something in the order I have written them :-)

My former masters would say my language is Russian although I speak a few other dialics much better and a Russian will tell you I speak Russian crassly. I was taught English as were most who showed aptitude in science although now living in an English speaking world it wasn't good enough :-)

Orac became my sort of hero because I would choose whether or not I would answer questions for my former masters as most of the politcal police where rather stupid.

I was given political asylum by Australia in 1996 and am a proud Australian citizen although I currently reside in USA because of my work. I really miss Australia and all my friends at ANU ... very home sick .. can you get homesick for a country you only call home for 10 years?

Religion was very discouraged in my upbringing whilst tolerated there was definite frowning upon.

My area of expertise is modelling astrophysics and particle and high energy physics.

I am slowly looking at religion but I find it very hard alot seem to want to grab you and brainwash you, I know that is probably harsh but from where I come from anyone trying to force you to "think this way" ... umm theres an expression ... gets my back up .. I think? I am reading a few books but alot of them are hard going ... one of my friends calls them "fire and brimstone" but it doesn't really make sense to me.

Well that I think covers me :-)
Posted By: Revlgking Re: the mystery of time and light - 08/13/11 03:44 AM
Originally Posted By: Orac
Orac was a fictional computer in the TV series Blake's 7...

Nationality Tatar, from Uzbekistan, from the former USSR and there is something in the order I have written them :-)


Orac became my sort of hero ...

I was given political asylum by Australia in 1996 and am a proud Australian citizen ... I currently reside in USA because of my work....

Religion was very discouraged in my upbringing whilst tolerated there was definite frowning upon.

My area of expertise is modeling astrophysics and particle and high energy physics.

I am slowly looking at religion ... very hard. A lot seem to want to grab you and brainwash you, I know that is probably harsh but from where I come from anyone trying to force you to "think this way" ... umm theres an expression ... gets my back up ... I think?

I am reading a few books but a lot of them are hard going ... one of my friends calls them "fire and brimstone" but it doesn't really make sense to me...
Thank for the excellent summary of your journey, so far. Rest assured: While I respect the right of anyone to believe what they freely choose to believe, Fire-and-brimstone Christianity makes little sense to many open-minded Christians.

By the way, after studies and work experience in Canada I did some post graduate studies in theology at Boston University School of Theology--Liberal-thinking Methodists (1954--1955)--very open-minded to the sciences and to other open-minded forms of religion, not just Christian. I abhor and resent narrow religions that try to brain wash people. Thank GOD, there are those which do not.
Posted By: Bill S. Re: the mystery of time and light - 10/28/11 10:55 PM
Early in this thread I found:

Originally Posted By: Rede
That's nothing, Bill. When you reach Megastar they give you a limo and chauffeur.


Rede, how can I ever trust you again?
Posted By: redewenur Re: the mystery of time and light - 10/29/11 08:29 AM
Still waiting Bill? Tut-tut. They must have got lost in the multiverse. Still, just think, somewhere out there is a chauffeur driven Bill S. Either that, or it's a serious case of time dilation.
Posted By: Bill S. Re: the mystery of time and light - 10/29/11 11:51 AM
I should have known there would be a get-out clause. frown
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