Universe expanding or time speeding up?


by CosmologyHobbyist
Tags: expanding, speeding, time, universe
CosmologyHobbyist
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#1
Dec29-09, 09:12 AM
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Redshift measurements show the universe is expanding, and the rate of expansion has been accelerating since 5 (is that the correct number?) billion years ago. It occurred to me that instead of space expanding (a concept with a few unresolved problems such as what is dark energy?), the same redshift effect could be caused by time speeding up over the life of the universe.

This would appear similar to the redshift that occurs when light leaves a gravity well. Time runs "slower" in intense gravity. As the light leaves the gravity well, it is redshifted as it moves out into space where time "runs faster".

Perhaps someone can tell me what is the correct terminology for "fast" time and slow "time". (Is time "dilation" slow time? What is the term for "fast" time? Un-dilation? :)

My question 1 is: Is time "speeding up" exactly the same as space expanding? It seems to me the answer is no, space expansion is overcome by gravitational structures such as galaxies, and it not reshaping the universe on such small scales. It seems to me that if time is speeding up, it would have impact down to the subatomic level. Can anyone explain if the two ideas (space expansion vs time speeding up) are interchangeable?

Question 2: Searching on the internet I found someone already proposing this idea: Jose Senovilla. Where does this man stand in mainstream science? Is he for real or far out? Is there anyone else working with this idea? Is there anyone creditable working with this idea?

Summary: I am expecting that the idea of time speeding up over the life of the universe breaks down and falls apart at some point. Can anyone explaing to me what shoots down this line of thinking? Or maybe someone can tell me that it is a valid line of thought that is being considered in the mainstream?
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S.Vasojevic
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Dec29-09, 09:58 AM
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If time speeds up uniformly in whole universe, we wouldn't even notice it, or be able to measure it. It would appear to us just the same.
Consider light that goes twice faster than now. Now you take clock to measure it's speed. Clock also runs twice faster - result is the same.
CosmologyHobbyist
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Dec29-09, 10:25 AM
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Right, right, right. Of course.

BUT - When looking back into the the very distant parts of the universe, which means simultaneously looking back in time to the origins of the universe, the change in the rate of time would cause the light from distant galaxies to undergo exactly the same redshift that is currently attributed to space expanding.

In other words, you could have a steady-state universe, which gives the appearance of an expanding universe, if time is "speeding up" over the life of the universe.

If the universe is steady-state, and time is speeding up, then instead of the universe expanding from a "point" 13 billion years ago, instead, 13 billion years ago time was standing still. It would cause the same record in the redshifts observed.

I personally think this must break down and fall apart somewhere, but I am not sure where. I am also disappointed I cannot find a debunking of this idea anywhere. Surely this is not a new alternative? Space expanding or time speeding up, its very interchangeable, and shouldnt someone have looked at it already?

Garth
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Dec29-09, 11:29 AM
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Universe expanding or time speeding up?


What you are discussing is a conformal model of cosmology.

You can have two models conformally related to each other with two time systems

The important question is does the time parameter "t" have physical significance; that is, does it relate to some clock in each model that is usable in physical experiments?

Forms of coordinate time can be anything we want them to be through conformal transformations - that is why it is important to connect any particular definition of time with a physical process to ensure that it is physically significant.

So, for example, we can define two physically significant times as follows.

Sample two photons, one emitted by a caesium atom the other sampled from the CMB radiation.

First time system: In the standard LCDM model of an expanding universe, with regular atomic clocks and fixed atomic meter rulers, the standard of time is the "atomic" second defined as the duration of exactly 9.19263177x109 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom.

Second time system: A "photonic" second, may be defined as the duration of exactly 1.604x1011 periods of the radiation corresponding to the peak of the CMB black body spectrum.

Both systems of time measurement are physically significant and agree with each other in the present epoch, although they will diverge from each other at other times.

When compared to the "atomic" clock system, the "photonic" clock system model, extrapolated back to the earliest moments of the BB, diverges to (-) inifinity as atomic time t->0.

Thus in this model we can recover "an infinitely old universe" within an apparently finite (as measured by an "atomic" clock) BB paradigm. Furthermore it will be static in size as measured by the "photonic" metre.

To give this "photonic" system of clocks and rulers a physical reality (i.e. physically consistent) you will have to make atomic masses grow exponentially with time, this will require an alternative theory of gravitation and cosmology.

However in such a model, if ephemeris time is that measured in the "photonic" system, (as it was in SCC), then the Pioneer spacecraft will appear to have an anomalous sunwards acceleration of cH or 6.69×10−8 cm.sec−2; such an acceleration aP = (8.74±1.33)×10−8 cm.sec−2 is actually observed. (Allowing for drag and radiation non-inertial forces and uncertainty in H.)

Garth
S.Vasojevic
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Dec29-09, 11:56 AM
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Quote Quote by Garth View Post
However in such a model, if ephemeris time is that measured in the "photonic" system, (as it was in SCC), then the Pioneer spacecraft will appear to have an anomalous sunwards acceleration of cH or 6.69×10−8 cm.sec−2; such an acceleration aP = (8.74±1.33)×10−8 cm.sec−2 is actually observed. (Allowing for drag and radiation non-inertial forces and uncertainty in H.)

Garth
Well I was about to writte that that model would settle Pioneer anomaly.


To give this "photonic" system of clocks and rulers a physical reality (i.e. physically consistent) you will have to make atomic masses grow exponentially with time, this will require an alternative theory of gravitation and cosmology.
Could you elaborate this a bit more?
Garth
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Dec29-09, 02:35 PM
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Quote Quote by S.Vasojevic View Post

Quote Quote by Garth
To give this "photonic" system of clocks and rulers a physical reality (i.e. physically consistent) you will have to make atomic masses grow exponentially with time, this will require an alternative theory of gravitation and cosmology.
Could you elaborate this a bit more?
Yes conformal transformations between metrics changes the definition of both space and time units, metres and seconds, and also the masses of fundamental particles.

If the Einstein frame metric (of coordinates and units) [itex]g_({\mu}{\nu})[/itex] is transformed into the conformal metric [itex]g'_({\mu}{\nu})[/itex] then the Riemannian line element

[tex]d{\tau}^2 = g_({\mu}{\nu})dx^{\mu}dx^{\nu}[/tex]

is changed through

[tex]g_({\mu}{\nu}) \rightarrow g'_({\mu}{\nu}) = {\Omega}^2 g_({\mu}{\nu})[/tex]

to

[tex]d{\tau}'^2 = g'_({\mu}{\nu})dx^{\mu}dx^{\nu} = {\Omega}^2d{\tau}^2 [/tex]

and the constant mass, m, of a particle is transformed

[tex]m'(x^{\mu}) = {\Omega}^{(-1)} m[/tex].

Therefore we need a theory in which particle masses vary with position in space and time.

SCC did just this where [itex]\Omega[/itex] was simply the Newtonian Gravitational Potential, so masses varied with gravitational potential energy and cosmologically particle masses m(t) = mo exp(Ht).

Unfortunately the 2002 form of the theory did not seem to be supported by the results of the Gravity Probe B experiment!

Garth
edpell
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#7
Dec29-09, 03:50 PM
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It is inertia that sets the timescale of the universe. If inertia is decreasing we will get more distance traveled in one second by an object that experiences a force F. So from the perspective of someone not experiencing the inertia decrease the folks experiencing the inertia decrease would appear to be moving faster.

So maybe inertia is changing with time?
CosmologyHobbyist
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Dec29-09, 10:11 PM
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I once read that half million years after BB, electrons were measured to be 30% more massive than at present. I am unable to google up a reference, perhaps someone knows one. Is this likely explained by time moving at a different rate than today? Or is that a less likely explanation? (Unfortunately, I believe Hubble redshifts require time to be speeding up over the life of the universe; while electron mass decreasing requires time to be slowing down of the life of the universe, correct??)

I've read a lot on space expanding. As baffling as the expansion of space is, to me it seems equivalent to the rate of time changing. Yet I do not run into much discussion on the topic of the rate of time not being constant - why is it not under consideration? Reality may end up with a mix of the two.

Evidence, evidence, evidence! What does the evidence say? Or what does evidence disqualify? What are the two extreme cases for : 1) All Hubble redshift attributable to space expanding (this gets high points for the amount of discussion I can find); other extreme: All Hubble redshift attributed to time speeding up (not much discussion found, and possibly evidence found against it). 3) Could reality fall between the two extremes, or is the evidence for 100% space expansion, 0% change in rate of time? I am very curious as to why all the discussion falls on one side of this argument, no one discusses the other side. I hope it is because of evidence, and not because I am the first to think outside of the box! :D
petm1
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Dec29-09, 11:59 PM
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I once read that half million years after BB, electrons were measured to be 30% more massive than at present.
Who did the measuring?
petm1
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Dec30-09, 01:49 AM
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Quote Quote by Garth View Post
Unfortunately the 2002 form of the theory did not seem to be supported by the results of the Gravity Probe B experiment!Garth

Why?
Garth
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Dec30-09, 02:04 AM
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Quote Quote by petm1 View Post
Quote Quote by Garth
Unfortunately the 2002 form of the theory did not seem to be supported by the results of the Gravity Probe B experiment!Garth
Why?
See Alternative theories being tested by Gravity Probe B .

Garth
petm1
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Dec30-09, 02:33 AM
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Quote Quote by S.Vasojevic View Post
If time speeds up uniformly in whole universe, we wouldn't even notice it, or be able to measure it. It would appear to us just the same.
Consider light that goes twice faster than now. Now you take clock to measure it's speed. Clock also runs twice faster - result is the same.
But time does not change uniformly everywhere in the whole universe, except at extremes like maybe a black hole or a photon, as every frame of reference is it own time. Atoms are the only thing that I can think of that move uniformly throughout our visible universe.
Garth
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Dec30-09, 07:24 AM
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Quote Quote by petm1 View Post
Quote Quote by S.Vasojevic
If time speeds up uniformly in whole universe, we wouldn't even notice it, or be able to measure it. It would appear to us just the same.
Consider light that goes twice faster than now. Now you take clock to measure it's speed. Clock also runs twice faster - result is the same.
But time does not change uniformly everywhere in the whole universe, except at extremes like maybe a black hole or a photon, as every frame of reference is it own time. Atoms are the only thing that I can think of that move uniformly throughout our visible universe.
The point I have made is that if the mass of atomic particles increases monotonically with cosmological time, then atomic clocks would 'speed up' "uniformly in the whole universe".

This would occur for example in a mass field theory such as Fred Hoyle's described in On the Origin of the Microwave background

The problem would be that we would not be able to notice this increase in clock rate unless there was another kind of clock to measure it against.

In SCC theory such a clock would have been provided by the photons in the microwave background.

The secular increase in atomic clock rates would then be observed as cosmological red shift, a thought pertinent to the OP question.

Garth
DevilsAvocado
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Dec30-09, 08:45 AM
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Quote Quote by CosmologyHobbyist View Post
... In other words, you could have a steady-state universe, which gives the appearance of an expanding universe, if time is "speeding up" over the life of the universe.
... I personally think this must break down and fall apart somewhere, but I am not sure where. ...
Excuse the layman, but...

Don’t we overlook one crucial fact here? Wouldn’t it be impossible to see the CMB in a steady-state universe?? The CMB photons would be long gone, ... or ...?? As opposed to the expanding universe:



Ned Wright: Why haven't the CMBR photons outrun the galaxies in the Big Bang?
Garth
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Dec30-09, 08:58 AM
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Quote Quote by DevilsAvocado View Post
Excuse the layman, but...

Don’t we overlook one crucial fact here? Wouldn’t it be impossible to see the CMB in a steady-state universe?? The CMB photons would be long gone, ... or ...?? As opposed to the expanding universe:
Actually DevilsAvocado no!!

You are correct for the actual Steady State Theory in which atomic time is the standard and atomic clocks are 'regular', however CosmologyHobbyist was using the word 'steady-state' in a loose way to mean an infinitely old universe, as measured by his clocks that are 'speeding up'.

In the model I described, in which atomic particle masses are monotonically increasing and therefore atomic clocks are speeding up and metre rulers (made of atoms) are shrinking, the universe may be measured by the energy and frequency of photons.

The energy of the photon gives the measure of mass through m = E/c2 and the inverse of its frequency gives the measure of time, length is simply c(t2 - t1).

If you look into the past then atomic processes appear slowed down (red-shifted) and as the frequency of photons in the CMB increases asymtotically the closer you get to the BB then time as measured by those photons becomes stretched out, so the moment of the BB itself is projected back to minus infinity.

You have replaced a universe expanding from a BB 13.7 Gyrs ago, which has regular atomic clocks and fixed steel 'atomic' rulers, with a static universe of infinite age, which has atomic clocks that speed up and shrinking steel rulers.

Both alternative models are the same thing, it just depends on what sort of clock you use to measure it!

Garth
CosmologyHobbyist
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Dec30-09, 10:59 AM
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Dear Petm1, I stand corrected. The actual figure is for change in ratio of proton to electron mass, (not electron mass alone) and the amount is in millionths of a percent (not 30%). In answer to question - Who measured it (if still interested) :
Reinhold E, Buning R, Hollenstein U, Ivanchik A, Petitjean P, Ubachs W.
But the results are in question, and would indicate change in nuclear strongforce, not rate of time, so becomes irrelevant to this discussion. Sorry for the bunny trail, but I'm glad at least I was able to find a lead and follow it up!
DevilsAvocado
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Dec30-09, 11:14 AM
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Quote Quote by Garth View Post
... Both alternative models are the same thing, it just depends on what sort of clock you use to measure it!
Thanks for the explanation!

This is 'weird' and interesting, and I like it! I also like to ask 'awkward' questions (genetic defect ). Not to be 'rude', just to maybe contribute to the 'fine-tuning' of a theory (hopefully ).

Questions:

Q1) Olbers' Paradox is solved partly by the expansion of universe. I can see that your theory solves this through "speeding time & shrinking rulers". But (as to my understanding) Olbers' Paradox is solved mainly by the fact that the age of universe is finite, 13.7 billion years. How do you solve this in a static universe of infinite age?

Q2) If the atoms are shrinking, what happens to the Fine-structure constant (electromagnetic interaction α = 0.08542455)? Which hold atoms together to make molecules, and If α were > 0.1 stellar fusion would be impossible...?

Q3) If your theory fixes Q2, how could we synchronize such a 'massive event' in an infinite universe? Unsynchronized neighboring parts of an infinite universe would make a great New Year's fireworks!

Q4) (Warning: Stupid question!) How can you measure any difference in photon energy (m = E/c2) and photon frequency (c(t2 - t1)) if all 'apparatus' (time/rulers) are 'flexible'?

Q5) How do you avoid a static and infinite universe from turning into a singularity (pretty fast)? This worried Einstein and Schwarzschild contributed with the solution to do it:

[tex]r_{s} = \frac{2GM}{c^{2}}[/tex]
Garth
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Dec30-09, 12:27 PM
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Quote Quote by DevilsAvocado View Post
Thanks for the explanation!

This is 'weird' and interesting, and I like it! I also like to ask 'awkward' questions (genetic defect ). Not to be 'rude', just to maybe contribute to the 'fine-tuning' of a theory (hopefully ).

Questions:
These are good questions, I shall interleave the answers.
Q1) Olbers' Paradox is solved partly by the expansion of universe. I can see that your theory solves this through "speeding time & shrinking rulers". But (as to my understanding) Olbers' Paradox is solved mainly by the fact that the age of universe is finite, 13.7 billion years. How do you solve this in a static universe of infinite age?
In the "photonic" way of measuring the universe distant stars are still red-shifted, although the effect is interpreted as a time dilation effect and not an expansion effect. It is this red-shift which resolves the paradox, as indeed it does in an open, infinite, universe in the standard theory.
Q2) If the atoms are shrinking, what happens to the Fine-structure constant (electromagnetic interaction α = 0.08542455)? Which hold atoms together to make molecules, and If α were > 0.1 stellar fusion would be impossible...?
The Fine structure constant is invariant. All you are changing are the masses of atomic particles, the size and transition energies of atoms are dependent on the atomic mass.
Q3) If your theory fixes Q2, how could we synchronize such a 'massive event' in an infinite universe? Unsynchronized neighboring parts of an infinite universe would make a great New Year's fireworks!
The universe is not necessarily infinite, in fact in SCC it was closed, however it would be infinite in age, which gives plenty of time for even disparate parts of the universe to be synchronized.
Q4) (Warning: Stupid question!) How can you measure any difference in photon energy (m = E/c2) and photon frequency (c(t2 - t1)) if all 'apparatus' (time/rulers) are 'flexible'?
You count the beats! It is the photon which becomes the clock.

As I said in my post 4:
Second time system: A "photonic" second, may be defined as the duration of exactly 1.604x1011 periods of the radiation corresponding to the peak of the CMB black body spectrum.
Q5) How do you avoid a static and infinite universe from turning into a singularity (pretty fast)? This worried Einstein and Schwarzschild contributed with the solution to do it:

[tex]r_{s} = \frac{2GM}{c^{2}}[/tex]
There are two possible ways of proceeding here.

One possibility is simply to take GR cosmology and decide to define time from a CMB photon as above, the result is a static, infinitely old, universe that is simply a conformal projection of the GR universe.

It is the same model but the dynamics look different because of the way you are measuring it, and it is stable and will not collapse.

Put that another way, if the GR universe did collapse into a Big Crunch then the "photonic" system of measuring would still yield a static universe, but it would imply masses were now decreasing and rulers expanding etc. The problem would be that there would be no physical reason for masses to behave in this way.

However SCC was an attempt to modify GR and give a reason for such a variation of mass, - the inclusion of gravitational potential energy. The result was a static and closed universe.

Furthermore, its conformal transformation into its Einstein frame with constant mass etc. yielded a linearly expanding universe and a theory that gave all the same predictions of GR in tests of particle and photon trajectories through vacuum. These included all tests right up to the Gravity Probe B experiment!

Ah well, never mind!!

Garth


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