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#55801 - 04/26/16 01:08 PM Is the Steady State dead?
Bill S. Offline
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Registered: 08/20/10
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I think I've sorted the computer problem that has kept me off line for a while.

Good to see that Bill is still posting great links about our ancestors. I have some catching up to do.

I'm not really suggesting a revival of the Steady State, but one of its proposals crept into my thinking about gravity. I'm not posting this in "New Theories" as it is neither new, nor a theory.

For clarity I follow (roughly) John Gribbin’s. terminology in which:
Universe = that which started with the Big Bang; universe = any other universe we might hypothesize and cosmos = everything that exists, or could possibly exist.

I use infinite/eternal in the sense in which these terms are normally used by scientists, although I suspect that this is often an oversimplification.

The Universe started with the Big Bang, and is a finite part of an infinite cosmos.

The cosmos contains a balance of what we perceive as “ordinary” matter and dark matter. The BB constituted a fluctuation which disrupted the balance of ordinary/dark matter.

The nascent Universe was composed (almost?) entirely of the raw material for ordinary matter.

The steady state theory; if I remember correctly; proposed that the necessary rate of creation of new matter would be about one H atom per m^3 per 10^9 years, and that this would facilitate the expansion of the Universe.

Could it be that, as the Universe expands, dark matter is “leaking” into it at roughly that rate, and is responsible for the observed acceleration of expansion?

If dark matter is entering the Universe at a rate equivalent to one H atom per m^3 per 10^9 years, it might remain undetected until gravity pulls it into clumps around ordinary matter, when its gravitational influence is detectable.
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#55803 - 04/27/16 05:07 AM Re: Is the Steady State dead? [Re: Bill S.]
Orac Offline
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Good to see you still thinking about things Bill S.

Okay lets me first deal with an inconsistency in you post

Originally Posted By: Bill S.
cosmos = everything that exists, or could possibly exist.

That is a very clear definition then you follow with this.

Originally Posted By: Bill S.
The Universe started with the Big Bang, and is a finite part of an infinite cosmos.

The use of the word infinite creates the same problem as me talking about running forever on a circular track. It can be "true" in some ways but yet it is clear the physical enviroment is itself finite. I find the use of the word infinite as both confusing and wrong as it is when used with a running track.

Think carefully now, under that definition of cosmos the expansion of the universe is actually into the future cosmos. Time therefore must be considered as an integral part of the cosmos as a discrete component. I am not saying this is right or wrong just an inevitable consequence of the definition.

Originally Posted By: Bill S.
The cosmos contains a balance of what we perceive as “ordinary” matter and dark matter. The BB constituted a fluctuation which disrupted the balance of ordinary/dark matter.

The nascent Universe was composed (almost?) entirely of the raw material for ordinary matter.

It also contains a balance which is somehow related to past and future and must contain time, which is the flip side of those statements smile

Originally Posted By: Bill S.
Could it be that, as the Universe expands, dark matter is “leaking” into it at roughly that rate, and is responsible for the observed acceleration of expansion?

There are many theories (you need extra dimensions on space) around this sort of idea but there are also very tight limits put on them by specific tests being

a) LHC results limits on large scale extra dimensions
b) Upper limits to submillimetre-range forces from extra space-time dimensions

Your idea itself is very general and covers a wide range of actual scientific theories such as Brane Cosmology and leaking Neutrinos.

The problem for all theories is tests on Earth put very very tight limits on these cosmological ideas.


Edited by Orac (04/27/16 05:08 AM)
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#55805 - 04/27/16 07:49 PM Re: Is the Steady State dead? [Re: Bill S.]
Bill S. Offline
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Originally Posted By: Orac
The use of the word infinite creates the same problem as me talking about running forever on a circular track.


This is why I attached a proviso to the use of “infinite”. I suspected you would try to foist me with my own petard. For the sake of this discussion, let’s just drop the “infinite”. Does that make any difference?
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#55807 - 04/28/16 02:52 AM Re: Is the Steady State dead? [Re: Bill S.]
Orac Offline
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Nope that was my confusion your definition of cosmos was self encompassing and in some ways defined something finite (like the running track).

So are you comfortable with the position you have put time in?
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#55808 - 04/28/16 09:38 AM Re: Is the Steady State dead? [Re: Bill S.]
Bill S. Offline
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Registered: 08/20/10
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Loc: Essex, UK
Originally Posted By: Orac
So are you comfortable with the position you have put time in?


For the sake of this discussion I am comfortable with the idea that in an infinite cosmos time goes infinitely in both directions. Time in the Universe then becomes just a “section” within that. Would that work?

This is a simplification, and like analogies, simplifications should not be taken beyond their boundaries.
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#55809 - 04/29/16 09:36 PM Re: Is the Steady State dead? [Re: Bill S.]
Bill S. Offline
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In the situation suggested in the OP I suspect there would be serious problems involving time and distance, especially as matter particles would travel at sub-luminal speed. A solution might be to introduce extra dimensions, such that balanced cosmos and unbalanced Universe could occupy what we perceive as the same space; along the lines of David Deutsch’s version of the multiverse.

That's probably a step too far into fairytale physics. smile
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#55811 - 04/30/16 07:03 AM Re: Is the Steady State dead? [Re: Bill S.]
Orac Offline
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You actually expressed my concern you have put time and distance in the flat earth syndrome. You are using the here and now and then extending it infinitely without the thought your "here and now" are very subjective.

The lesson from our science history is you need to be careful extending time and distances they may not be flat and linear even on Earth smile

Perhaps a challenge for you, prove to yourself time, and space as independent things are linear. Always good for a think session.


Edited by Orac (04/30/16 07:08 AM)
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#55813 - 04/30/16 05:05 PM Re: Is the Steady State dead? [Re: Bill S.]
Bill S. Offline
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Registered: 08/20/10
Posts: 3570
Loc: Essex, UK
Quote:
Perhaps a challenge for you, prove to yourself time, and space as independent things are linear.

If, at a location that is stationary relative to Earth, I measure time; then, later measure it again, at the same location; if I compare the measurements I might conclude that time is linear.

If I do the same thing, but take the first measurement in deep space, and the second in the gravity well of a planet, I might conclude that time is non-linear.

Therefore, I might reason that time is linear locally, but non-linear globally. OK, I see a problem arising there, but one step at a time.
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#55817 - 05/01/16 01:34 PM Re: Is the Steady State dead? [Re: Bill S.]
Orac Offline
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Registered: 05/20/11
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Loc: Currently Illinois, USA
Originally Posted By: Bill S.
Therefore, I might reason that time is linear locally, but non-linear globally. OK, I see a problem arising there, but one step at a time.

Yes its the flat earth locally, round earth from distance problem. Black holes for example would have very slow moving time but the prediction is you would not notice it.

To do anything conclusively you need measurements from things that aren't local and when we look at things like pulsars, novas and super nova there are some interesting results.

There are in fact a number of theories in which time is actually slowing thru the universe and it's not as easy to dismiss them as you might think.

If I attack the problem mathematically it gets worse you can have have no time, two times, and time and space switching dimensions you see this problem come up a lot with wormholes in GR.

However this is not about what others or I think, its about what you think so lets leave that there except for a joke.

Joke: An off the wagon creationist dies and ends at the pearly gates. St Peter looks at the book and finds he is to be sent to hell for loss of faith. The creationist complains but the scientists have all this evidence the earth is billions of years old and the bible says it's only 6000, how was I to deal with that. What you overlooked the obvious that it is written in GOD years and with that he was cast down to start his time.


Edited by Orac (05/01/16 01:48 PM)
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#55818 - 05/02/16 01:53 AM Re: Is the Steady State dead? [Re: Orac]
Bill Offline
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Registered: 12/31/10
Posts: 1858
Loc: Oklahoma, USA
Joke: The Atheist and the Bear

An atheist was taking a walk through the woods. 'What majestic trees! What powerful rivers! What beautiful animals!', he said to himself.

As he continued walking alongside the river he heard a rustling in the bushes. Turning to look, he saw a 7 foot grizzly charging towards him.

He ran as fast as he could up the path. Looking over his shoulder he saw that the bear was closing in on him. His heart was pumping frantically and he tried to run even faster.

He tripped and fell on the ground. He rolled over to pick himself up but saw the bear raising his paw to take a swipe at him.

At that instant the atheist cried out: 'Oh my God!...'

Time stopped.
The bear froze.
The forest was silent.

It was then that a bright light shone upon the man and a voice came out of the sky saying:

'You deny my existence for all of these years, teach others I don't exist and even credit creation to a cosmic accident. Do you expect me to help you out of this predicament? Am I to count you as a believer?'

The atheist looked directly into the light.

'It would be hypocritical of me to suddenly ask you to treat me as a Christian now, but perhaps, could you make the BEAR a Christian?'

'Very well, 'said the voice. The light went out, and the sounds of the forest resumed.

And then the bear lowered his paw, bowed his head and spoke: 'Lord, bless this food which I am about to receive and for which I am truly thankful, Amen.'
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#55822 - 05/04/16 08:36 PM Re: Is the Steady State dead? [Re: Bill S.]
Bill S. Offline
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Registered: 08/20/10
Posts: 3570
Loc: Essex, UK
The problem I thought might arise involved a thought experiment.

An astronaut is in deep space. She measures the minimal effects of gravity, then measures time.

Another astronaut is 1,000,000 ly away. The gravitational effects are identical. He measures time.

It’s a thought experiment, so they have instantaneous communication. When they compare their time measurements, they are identical.

Would they be justified in concluding that time is linear globally?
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#55824 - 05/04/16 10:40 PM Re: Is the Steady State dead? [Re: Bill S.]
Bill Offline
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Registered: 12/31/10
Posts: 1858
Loc: Oklahoma, USA
Under the conditions as stated they could hypothesize that time is linear. However, they would really need to make the same observations under different gravitational conditions to test their hypothesis. IF they didn't realize that different gravitational conditions existed they would probably be more likely to accept the hypothesis as true.

In a somewhat similar situation it is believed that what an object is made of has no effect on how it behaves in a gravitational field. I believe there is currently a satellite in orbit, or about to be in orbit, to test whether gravity affects different materials the same way. It has samples of different metals, I forget which ones, and will see if they experience exactly the same acceleration due to gravity. Presently we assume it does, but we haven't done extremely fine tests, since they are hard to do. This test will check the idea much more precisely than has been done before.

I don't think that anyone really thinks that they will not respond precisely the same, but science is always trying to find out if what we think is true is really true.

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

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