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#41371 - 11/08/11 08:30 PM Question to Physics experts Re: Light & Space
SWMayers Offline
Junior Member

Registered: 10/19/11
Posts: 4
If given that c is the speed of light, if a photon, say, travels in open empty space for one second, how far will the photon be from its starting point in one second?

You might say this would be obviously, c, but what about the consideration of the expansion of the Universe during this second? Is this distance c + (expanded space) or is it still c, where c = (expanded space) + X?

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#41373 - 11/09/11 06:58 AM Re: Question to Physics experts Re: Light & Space [Re: SWMayers]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Space is expanding not stretching so the answer is c.

If what you said was real you would also be getting taller, wider, fatter because you would also be stretching you and earth are you are both in timespace as well.

Imagine you in a ballon and its being blown up the walls are moving out but nothing is changing in the ballon.

For us the walls for timespace are racing out into the nothingness so space is getting bigger and bigger.

Assuming there are no constraints, which I can not give you a scientific guarantee of, eventually the universe will become a bleak empty place and when we look up at the heavens there will be few stars as the matter of the universe will be vastly spaced out.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41375 - 11/09/11 08:48 AM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
ADVANCE DISCUSSION MAY BE BEYOND YOUR PHYSICS

The question the expanding universe always brings up is how can the universe expand if it is the universe into what is it expanding and whats this edge look look.

This is in the technical domain called the universe event horizon. In GR/SR dominant days this event horizon was considered absolute as was like a black hole horizon. Things simply ceased to exist in our space when they crossed them.

With the rise of QM as not only real and important but consolidated in science terms this view of event horizons became untenable.

QM information as represented by tiny spins could not be destroyed much as we tried. QM information does not see gravity like matter sees gravity because they are little waves and so they can not simply be crushed out of existance at a black hole event horizon.

This tenant was eventually accepted by Stephen Hawking who when he incorporated the idea into the GR/SR mathematics came up with a remarkable conclusion. That based upon the Quantum Information the event horizons of black holes must have temperature and there emit radiation, named after him as Hawking Radiation. It spawned a whole new area of study called black hole thermodynamics (http://en.wikipedia.org/wiki/Black_hole_thermodynamics).

In the meantime QM had advanced tremendously and understanding the implications of what QM was implying we created out first artifical equivalents of event horizons in glass and fibre optics in 2008.

http://spectrum.ieee.org/aerospace/astro...g-optical-fiber
http://physicsworld.com/cws/article/news/33256

These experiments have continued getting ever more advanced and many showing emission which would be characterised as Hawking radiation.

In the meantime QM turned it's sites back on the universe event horizon.

Way back in 1976 Bill Unruh had made the realization that GR/SR implied that an inertial observer would see temperature. In other words if you accelerate a thermometer it will record a temperature. At the time it was one of those hotly debated odities and largely ignored.

However for QM this was a big deal especially out on the universe event horizon. For QM whats on the inside of is the same as what is on the outside except for QM information.

Where this leads QM is that our space is simply the energy filled section of a much bigger empty space.

My english is not up to simplifying this down so I will use wiki text from unruh effect entry (http://en.wikipedia.org/wiki/Unruh_effect)

Quote:

Vacuum interpretation

In modern terms, the concept of "vacuum" is not the same as "empty space", as all of space is filled with the quantized fields that make up a universe. Vacuum is simply the lowest possible energy state of these fields, a very different definition from "empty".

The energy states of any quantized field are defined by the Hamiltonian, based on local conditions, including the time coordinate. According to special relativity, two observers moving relative to each other must use different time coordinates. If those observers are accelerating, there may be no shared coordinate system. Hence, the observers will see different quantum states and thus different vacua.

In some cases, the vacuum of one observer is not even in the space of quantum states of the other. In technical terms, this comes about because the two vacua lead to unitarily inequivalent representations of the quantum field canonical commutation relations. This is because two mutually accelerating observers may not be able to find a globally defined coordinate transformation relating their coordinate choices.

An accelerating observer will perceive an apparent event horizon forming (see Rindler spacetime). The existence of Unruh radiation could be linked to this apparent event horizon, putting it in the same conceptual framework as Hawking radiation. On the other hand, the theory of the Unruh effect explains that the definition of what constitutes a "particle" depends on the state of motion of the observer.

The (free) field needs to be decomposed into positive and negative frequency components before defining the creation and annihilation operators. This can only be done in spacetimes with a timelike Killing vector field. This decomposition happens to be different in Cartesian and Rindler coordinates (although the two are related by a Bogoliubov transformation). This explains why the "particle numbers", which are defined in terms of the creation and annihilation operators, are different in both coordinates.

The Rindler spacetime has a horizon, and locally any non-extremal black hole horizon is Rindler. So the Rindler spacetime gives the local properties of black holes and cosmological horizons. The Unruh effect would then be the near-horizon form of the Hawking radiation



This has massive implications

- Space no longer ends at the universe event horizon
- It's actually possible to have 2 or many "universes" in one big empty space is our universe unique to the empty universe?
- Are particles real or are they just the virtual effects expected


I am afraid we don't have alot of answer we have alot of questions.

The one thing we do predict if that view is correct the Higgs particle will not exist because remember particles are only virtual effects caused by inertia.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41376 - 11/09/11 07:09 PM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Revlgking Offline
Megastar

Registered: 01/17/07
Posts: 2311
Loc: markham (Thornhill), Ontario, ...
Originally Posted By: Orac
Space is expanding not stretching so the answer is c. ... For us the walls for time-space are racing out into the nothingness so space is getting bigger and bigger.
... eventually the universe will become a bleak empty place and when we look up at the heavens there will be few stars as the matter of the universe will be vastly spaced out.
Orac, I think I understand what you just wrote. However, I can't say that I understand what this means for us now, or even for those who come after us.
May add: Whenever I try to read articles about the latest findings, like the one, as follows, which you mentioned--
http://en.wikipedia.org/wiki/Unruh_effect --I have to admit I am a loss as to what it, especially the maths, is all about.
However, when I read you say--and note my edit
Quote:
I am afraid we don't have a lot of answers, we have a lot of questions.

The one thing we do predict, if that view is correct, is: It will be found that the Higgs particle will not exist, because, remember, particles are only virtual effects caused by inertia.
I don't feel quite so blank.
=====================
The story is told of an art teacher who, noticed that one of the students seemed lost in trance-like thought as he drew.
The teacher stopped and asked the student:
"What are you drawing?"
"I am drawing a picture of God" the student said.
"But no one knows what God looks like" said the teacher.
"They will when I am finished" said the student. smile


Voltaire(1694-1778), the French author, humanist, rationalist, & satirist was once asked his idea of God. He is credited with responding: "God is a circle whose center is everywhere and whose circumference nowhere."

Me? G.O.D. is an unfinished and individualized process-like concept . The child within me is happy using the imagination. However, the adult I am wants to add intellect, reason, science--with all those questions.

Sure I appreciate the role and value of childhood, but in no way do I object to facing the questions of life--even the tough ones without answers, yet.





_________________________
G~O~D--Now & ForeverIS:Nature, Nurture & PNEUMA-ture, Thanks to Warren Farr&ME AT www.unitheist.org

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#41377 - 11/09/11 10:57 PM Re: Question to Physics experts Re: Light & Space [Re: SWMayers]
Bill S. Offline
Megastar

Registered: 08/20/10
Posts: 3570
Loc: Essex, UK
Originally Posted By: O
Assuming there are no constraints, which I can not give you a scientific guarantee of, eventually the universe will become a bleak empty place and when we look up at the heavens there will be few stars as the matter of the universe will be vastly spaced out.


My understanding is that it is the galaxy groups that are moving apart. If this is the case would it not be that the gravitational force between the groups would lessen. Thus, the gravitational attraction within the groups, and individual galaxies, would become more dominant, pulling bodies closer together. should we not then see more stars as we look up?
_________________________
There never was nothing.

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#41378 - 11/09/11 11:36 PM Re: Question to Physics experts Re: Light & Space [Re: Bill S.]
Bill Offline
Megastar

Registered: 12/31/10
Posts: 1858
Loc: Oklahoma, USA
Originally Posted By: Bill S.
My understanding is that it is the galaxy groups that are moving apart. If this is the case would it not be that the gravitational force between the groups would lessen. Thus, the gravitational attraction within the groups, and individual galaxies, would become more dominant, pulling bodies closer together. should we not then see more stars as we look up?

That of course depends on some things we don't quite understand yet. For example, my understanding of dark energy is that after it pushes all the galaxies apart it will continue to push the stars in the galaxies apart, then all matter will be pushed apart, until even the subatomic particles are disintegrated. Of course this depends a lot on just what dark energy is and how it operates.

And someplace just recently I saw that somebody is questioning the reality of dark energy. He thinks that the apparent acceleration in the expansion of the universe is a problem with the measurement. Ah! here it is Physorg.com has the story.

Bill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#41379 - 11/10/11 03:04 AM Re: Question to Physics experts Re: Light & Space [Re: Bill]
Revlgking Offline
Megastar

Registered: 01/17/07
Posts: 2311
Loc: markham (Thornhill), Ontario, ...
Originally Posted By: Bill
[quote=Bill S.]... Of course this depends a lot on just what dark energy is and how it operates.... Bill
Is dark energy dark? If so, dark what? Black, Brown? whatever. Is there such a think as light energy?
_________________________
G~O~D--Now & ForeverIS:Nature, Nurture & PNEUMA-ture, Thanks to Warren Farr&ME AT www.unitheist.org

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#41380 - 11/10/11 03:18 AM Re: Question to Physics experts Re: Light & Space [Re: Revlgking]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Bill S exactly what Bill G said is correct I would have to know what the dark stuff is to know what will happen.

In my group we talk about space pressure because in some ways it's like air pressure or hydrolic pressure rather than dark energy or dark matter .. remember it's "dark" because we can't see it.

For Rev: I assume you use a remote on A TV. There is an invisible beam that you can't see because it's outside your eyes range of light. Does it make it any less real just because you can't see it, I mean we even call it an invisible beam yet you can see the result?

What I call space pressure because Dark Energy or Dark matter has become so distorted by the public in exactly the way you just did. Just because I can't see it doesn't mean I can't measure it's effect.

If you truely believed in only visible things then get up and walk to your TV and change channels.


Edited by Orac (11/10/11 03:19 AM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41381 - 11/10/11 03:39 AM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
The more interesting thing which I always find funny is people seem to ignore the interesting thing with QM version of the universe.

There could actually be a universe next door expanding like us and eventually we will collide. We have seen galaxies collide and QM opens the door our universe could actually collide with another.

Technically we would say two space event horizons met.

See we have no way of knowing how big the unenergized space is or if there are other universes doing the same as us. We could have a whole new layer on space and it could be a whole lot bigger than we even think of it now.

Everytime I see bubble wrap plastic I always wonder :-)


Edited by Orac (11/10/11 03:40 AM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41383 - 11/10/11 05:50 AM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Ethan over at "starts with a bang" has put up a background of physics fundemental constants which will aid if we have discussions beyond the depth we have covered so far.

http://scienceblogs.com/startswithabang/2011/11/are_the_fundamental_constants.php

This covers the finding the universe expansion may not be uniform.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41388 - 11/10/11 03:53 PM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Bill Offline
Megastar

Registered: 12/31/10
Posts: 1858
Loc: Oklahoma, USA
That link is interesting. I generally check Ethan's blog, but not today, at least not until I saw your link. I have seen reports of this finding, but hadn't seen a good discussion of it. I have been dubious about it. But I have a lot of respect for Ethan and if he says there may be something to it I will accept that. Of course even he says it may have a problem of some sort. Once again we will just have to wait and see.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#41389 - 11/10/11 06:21 PM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Revlgking Offline
Megastar

Registered: 01/17/07
Posts: 2311
Loc: markham (Thornhill), Ontario, ...
Originally Posted By: Orac
For Rev: I assume you use a remote on A TV. There is an invisible beam that you can't see because it's outside your eyes range of light.

Does it make it any less real just because you can't see it ... ?
Orac, of course not. I acknowledge that there are very real and physical results which are caused by invisible beams of "light".

GENESIS 1:3: Then God commanded, "Let there be light"--and light appeared.
===============
For me, one of the qualities of what I call G.O.D. is light--pure, but mostly invisible, light. Then you add
Quote:
What I call space pressure, because Dark Energy or Dark matter has become so distorted by the public, in exactly the way you just did. Just because I can't see it doesn't mean I can't measure it's effect....
I distorted (twisted out of shape)? All I did was ask questions. When expert physicists use words like "dark matter" or "dark energy", is it not up to them to clarify what they mean?

SPACE PRESSURE?
You say you call it "space pressure"?. Is it similar to air pressure, like in a tire? Or blood pressure, like in the body? What do your fellow physicists say when you use the term "space pressure" ?
_________________________
G~O~D--Now & ForeverIS:Nature, Nurture & PNEUMA-ture, Thanks to Warren Farr&ME AT www.unitheist.org

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#41390 - 11/11/11 01:09 AM Re: Question to Physics experts Re: Light & Space [Re: Revlgking]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Yes those are good analogies.

If you look at a flat rubber tire tube the rubber has elasticity you pump air in you inflate the tire but there is pressure trying to expel the air from the rubber elasticity.

We see "unused" space as space with no energy at what we call zero potential as energy is put into it it assumes a new "ground" potential but that is not zero it is the equivalent of your tire pressure.

We are not sure if energy is pushed in or we are looking more like space as a sponge where it absorbs energy. From inside your tire your would not be sure if air was being pumped in or a vacuum cleaner was sucking air in. Push and pull of energy into zero energy space would look the same to us.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41392 - 11/11/11 02:55 AM Re: Question to Physics experts Re: Light & Space [Re: Orac]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
I guess I shouldn't really complain about finiter if our own scientists are going to do it

Here => (http://www.nature.com/nature/journal/v479/n7371/full/479006a.html)

Quote:

In September, CERN's council discussed a report on ‘The scientific significance of the possible exclusion of the SM Higgs boson in the mass range 114–600 GeV and how it should be best communicated'. The public version of the document, available online, emphasizes that the failure to find the Higgs would be just as exciting as a discovery. Privately, discussions are under way on whether the lab should announce that a negative result ‘excludes' the Higgs, which sounds final, or merely ‘disfavours' it — as 95% leaves a bit of wriggle room.


At best I will say they are trying to cover there Butts as they sold the LHC that it would find the higgs. At worst they are doing a finiter and trying to deny the result because they so cherish there little higgs particle. So I really hope it's more a PR disaster reason.

You know my view on the Higgs from the above discussion, finding the Higgs would cause us some angst with recent QM experimental observations, so for us no Higgs is good news.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41396 - 11/11/11 04:01 PM Re: Question to Physics experts Re: Light & Space [Re: Orac]
finiter Offline
Senior Member

Registered: 08/15/11
Posts: 211
Originally Posted By: Orac
I guess I shouldn't really complain about finiter if our own scientists are going to do it

You know my view on the Higgs from the above discussion, finding the Higgs would cause us some angst with recent QM experimental observations, so for us no Higgs is good news.

A very nice comment. But I would add a little more: 'The QM wizards will do the very same thing when confronted with such a situation; let us wait and see'.

'No Higgs' is good for my theory, and so I welcome it.

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#41398 - 11/11/11 05:30 PM Re: Question to Physics experts Re: Light & Space [Re: SWMayers]
Bill S. Offline
Megastar

Registered: 08/20/10
Posts: 3570
Loc: Essex, UK
I suspect that even if The Higgs is dead, it will not lie down very readily.
_________________________
There never was nothing.

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#41403 - 11/12/11 01:19 AM Re: Question to Physics experts Re: Light & Space [Re: finiter]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: finiter

A very nice comment. But I would add a little more: 'The QM wizards will do the very same thing when confronted with such a situation; let us wait and see'.

'No Higgs' is good for my theory, and so I welcome it.


No we don't believe in anything .. I have been consistantly told that, finiter :-)

While not true it's close.

QM basicly saying the universe is a whole lot bigger and weirder than science had it.

Man started this journey with the earth as the centre of the universe with stars, moon and sun circling us.

We came to realize that we were a planet and circled the sun. Then we realized that those stars were other suns.

Next we realized that different suns were part of galaxies and those galxies were moving about a thing called the universe.

QM is telling you that may not be the end of it because the universe event front is racing out into something and the QM information had to come from somewhere.

Perhaps as a final comment I should show a link to what happens when you put a schrödinger wave equation for a particle, the basis of all quantum mechanics, in a 3D box.

http://www.youtube.com/watch?v=ONvEH8tddbI


Edited by Orac (11/12/11 01:25 AM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41406 - 11/12/11 03:07 AM Re: Question to Physics experts Re: Light & Space [Re: SWMayers]
Bill S. Offline
Megastar

Registered: 08/20/10
Posts: 3570
Loc: Essex, UK
Originally Posted By: O
There could actually be a universe next door expanding like us and eventually we will collide.


Does QM make any proposals as to what the nature of the "space" between these universes be?
_________________________
There never was nothing.

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#41408 - 11/12/11 01:25 PM Re: Question to Physics experts Re: Light & Space [Re: Bill S.]
Orac Offline
Megastar

Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Unenergized empty space it's covered in the unruh section

Quote:

In modern terms, the concept of "vacuum" is not the same as "empty space", as all of space is filled with the quantized fields that make up a universe. Vacuum is simply the lowest possible energy state of these fields, a very different definition from "empty".





Edited by Orac (11/12/11 01:27 PM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#41410 - 11/12/11 03:19 PM Re: Question to Physics experts Re: Light & Space [Re: Orac]
finiter Offline
Senior Member

Registered: 08/15/11
Posts: 211
Originally Posted By: Orac
While not true it's close.
QM basicly saying the universe is a whole lot bigger and weirder than science had it.

Remember, 'while not true it's close' is a statement showing belief. The QM people rather believe it. But, there have been such 'close encounters' in the past. Laplace's law of determinism was one such 'close to end'. Now 'determinism' is out and 'chaos' is in. I think 'determinism' will come back.

I believe that the universe is much simpler than what is now being portrayed. However, if it is actually weirder, we have no choice but to agree with the QM concepts.

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