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Why Acceleration Of A Universe Might Happen


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#18 Flummoxed

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Posted 05 April 2019 - 04:20 AM

If space-time expanded I would think the planets would just slide and stay in their original positions, seeing that space is without friction. In order for your idea to work, distance itself would have to expand between systems. And I don't think that is possible without some ambient dark energy. Even an either would still be without friction. In other words it would take a tremendous amount of energy to push against the systems within the universe. Where's the energy in your idea without dark energy?

 

I think that 006 is saying that the universe is expanding due to the gravitational constant which is the same as saying dark energy did it. I think also that the difference in terminology is that the cosmological constant gets away from trying to understand what dark energy is or what drives the expansion. You just plug a variable constant in to the math and of you go.



#19 Flummoxed

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Posted 05 April 2019 - 04:24 AM

Yes this is true, as Susskind put it more properly though by stating ''the cosmological constant becomes significant when a universe gets large enough,'' in conjunction with the evidence supporting acceleration in the late phase. We do not however know why the cosmological constant becomes significant in later cosmology, but I am proposing this is because gravity is weakening.

 

I think I may have misunderstood your grammar here I think you meant gravity between galaxies is weakening, and not gravity within galaxies is weakening. Am I correct?



#20 Dubbelosix

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Posted 05 April 2019 - 05:15 AM

I think I may have misunderstood your grammar here I think you meant gravity between galaxies is weakening, and not gravity within galaxies is weakening. Am I correct?

 

Yes, whatever drives expansion, you can call it a cosmological constant -  instead of believing it is changing, the constant remains the same and it is in fact the gravitational interaction between galaxies that is weakening. Since the cosmological constant, is a constant, working against gravity and if gravity gets weaker, the cosmological constant only appears to change, when really it hasn't.



#21 Flummoxed

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Posted 05 April 2019 - 05:34 AM

Yes, whatever drives expansion, you can call it a cosmological constant -  instead of believing it is changing, the constant remains the same and it is in fact the gravitational interaction between galaxies that is weakening. Since the cosmological constant, is a constant, working against gravity and if gravity gets weaker, the cosmological constant only appears to change, when really it hasn't.

 

Thanks, just checking you hadn't gone (totally) mad :)



#22 devin553344

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Posted 05 April 2019 - 09:09 AM

The problem with dark energy is that it would be a continuous energy density. Therefore it would exert an acceleration equally in all directions. And no expansion is then possible. So technically the idea is garbage.



#23 Dubbelosix

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Posted 05 April 2019 - 10:59 AM

The problem with dark energy is that it would be a continuous energy density. Therefore it would exert an acceleration equally in all directions. And no expansion is then possible. So technically the idea is garbage.

 

No, the cosmological repulsive energy only needs to be stronger than its own gravitational binding to expand. It's the fact that gravity weakens as it expands and so this constant energy is being literally intensified giving us the impression the cosmological constant is somehow changing.



#24 Dubbelosix

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Posted 05 April 2019 - 11:00 AM

Susskind was right in my opinion... the cosmological constant does get significant on larger scales, at least gravity will provide us with an answer why.



#25 devin553344

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Posted 05 April 2019 - 01:52 PM

No, the cosmological repulsive energy only needs to be stronger than its own gravitational binding to expand. It's the fact that gravity weakens as it expands and so this constant energy is being literally intensified giving us the impression the cosmological constant is somehow changing.

 

Can you provide what physics principle dark energy relates to? I understand gravitation is a curvature of space-time. And what I stated is true for curvatures. Dark energy as a curvature of space-time can provide no expansion. In fact the statement is usually made that dark energy is not understandable to support it's inclusion in physics. And a leading physicist professor at Oxford seems to explain how dark energy need not exist at all: https://horizon-maga...-physicist.html


Edited by devin553344, 05 April 2019 - 02:04 PM.


#26 Flummoxed

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Posted 06 April 2019 - 08:03 AM

 And a leading physicist professor at Oxford seems to explain how dark energy need not exist at all: https://horizon-maga...-physicist.html

 

That link is inconclusive, the prof is simply questioning the validity of the results. It seems the astronomical observations don't require as much verification as particle or quantum observations. According to the prof dark energy may not exist, dark energy or the cosmological constant being einsteins biggest blunder, I wonder if the prof might be making a blunder, or just calling for more evidence of cosmological claims.



#27 Moronium

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Posted 06 April 2019 - 09:42 AM

That link is inconclusive, the prof is simply questioning the validity of the results. 

 

Yeah, he doesn't exactly "explain" anything, eh?  There are many different theories which dispense with dark energy.  For example, here's an excerpt from a paper authored by 5-6 physicists, which appears to be well researched.

 

We use the Szekeres inhomogeneous relativistic models in order to fit supernova combined datasets. We show that with a choice of the spatial curvature function that is guided by current observations, the models fit the supernova data almost as well as the LCDM model without requiring a dark energy component.

 

In this paper, we present a first analysis of apparent acceleration using the appealing Szekeres inhomogeneous models [25, 26]; see also [27] and references therein for a review of the models...The models have been investigated analytically by several authors [28, 29, 30, 31, 32, 33, 34, 36, 37, 38] and are regarded as the best exact solution candidates to represent the true lumpy universe we live in....In this scenario, apparent acceleration is due to the fact that we happen to live in one of the many underdense regions of the universe.

.

 

https://arxiv.org/pdf/0708.2943.pdf

 

The general idea is that the expansion is merely apparent, not real. If that's the case, that's one less reason to question and try to modify GR, I guess.

 

Another (of many) theories I've seen claims that the appearance of expansion is caused by difficulties created by SR,  with its postulation of relative simultaneity, and could be eliminated by adopting a preferred frame theory of relative motion.  I've long been highly critical of SR, and it wouldn't surprise if this is at least part of the explanation.


Edited by Moronium, 06 April 2019 - 11:22 PM.

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#28 devin553344

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Posted 06 April 2019 - 02:09 PM

That link is inconclusive, the prof is simply questioning the validity of the results. It seems the astronomical observations don't require as much verification as particle or quantum observations. According to the prof dark energy may not exist, dark energy or the cosmological constant being einsteins biggest blunder, I wonder if the prof might be making a blunder, or just calling for more evidence of cosmological claims.

 

Well they hid the results for years and years. Why? And I myself have examined experiment results and found them to be much less precise then what they claim. For instance the Planck constant is only good up to 6.62607'ish, but they give a value of 6.62607001. And that is just crazy talk. I find the same discrepancies in the electron mass, and other constants. Maybe there is something to the professors claim? I kinda think there is. It's an interesting topic, thanks for responding! :)


Edited by devin553344, 06 April 2019 - 02:10 PM.


#29 fahrquad

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Posted 06 April 2019 - 04:58 PM

There was a SciFi story that I read many years ago where a galactic federation considered life on Earth to be an infection and the rest of the galaxy was retreating from us.  I can't remember who wrote it, but I suspect it was Dr. Isaac Asimov.

 

https://en.wikipedia...ki/Isaac_Asimov



#30 Moronium

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Posted 06 April 2019 - 05:25 PM

The general idea is that the expansion is merely apparent, not real. If that's the case, that's one less reason to question and try to modify GR, I guess.

 

Another (of many) theories I've seen claims that the appearance of expansion is caused by difficulties created by SR,  with its postulation of relative simultaneity, and could be eliminated by adopting a preferred frame theory of relative motion.  I've long been highly critical of SR, and it wouldn't surprise if this is at least part of the explanation.

 

Speaking of dumping special relativity in favor of a preferred frame theory, John Stuart Bell, Karl Popper, and many others have suggested that the (re)adoption of such a theory would resolve some of the conflicts between QM and GR.  Popper went so far as to say QM "falsified" SR.

 

‘’I would say that the cheapest resolution is something like going back to relativity as it was before Einstein, when people like Lorentz and Poincare thought that there was an aether-a preferred frame of reference...’’  (J.S. Bell)

 

 

‘’We have to give up Einstein’s interpretation of special relativity and return to Lorentz’s interpretation and with it to...absolute space and time...’’ (Karl Popper)

 


Edited by Moronium, 06 April 2019 - 07:53 PM.


#31 VictorMedvil

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Posted 06 April 2019 - 10:43 PM

No, the cosmological repulsive energy only needs to be stronger than its own gravitational binding to expand. It's the fact that gravity weakens as it expands and so this constant energy is being literally intensified giving us the impression the cosmological constant is somehow changing.

 

I am not saying the cosmological constant itself changes rather that the force the holds space together is weakening the actual fabric is allowing expansion, why is the cosmological constant, expanding acceleration because the fabric of time-space is getting larger. If time-space is like a spring then  the springness of the universe is being lost as time-space expands. The rate at which energy would be required to put pressure on time-space is increasing over time thus the universe must be getting weaker as it expands.


Edited by VictorMedvil, 06 April 2019 - 10:48 PM.


#32 Flummoxed

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Posted 07 April 2019 - 04:11 AM

Yeah, he doesn't exactly "explain" anything, eh?  There are many different theories which dispense with dark energy.  For example, here's an excerpt from a paper authored by 5-6 physicists, which appears to be well researched.

 

.

 

https://arxiv.org/pdf/0708.2943.pdf

 

The general idea is that the expansion is merely apparent, not real. If that's the case, that's one less reason to question and try to modify GR, I guess.

 

Another (of many) theories I've seen claims that the appearance of expansion is caused by difficulties created by SR,  with its postulation of relative simultaneity, and could be eliminated by adopting a preferred frame theory of relative motion.  I've long been highly critical of SR, and it wouldn't surprise if this is at least part of the explanation.

 

The idea that there the expansion of space non homogenic is appealing and I think plausible 

" The physical reason for such an observation is that inside the under-dense region, there is less matter to slow down the expansion and therefore the expansion rate in the under-dense region is larger than what it is in an over-dense region or compared to the overall averaged rate of expansion."

They do not make it clear in the paper that the apparent expansion of space has a real component. The red shift indicates there is an increase in distance. Unless the light gets tired and loses energy as it comes towards us :( but that would be against the standard model, and not all galaxies are red shifted a handful are blue shifted, some of which are at the outer limits of the observable universe.



#33 Flummoxed

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Posted 07 April 2019 - 04:13 AM

Speaking of dumping special relativity in favor of a preferred frame theory, John Stuart Bell, Karl Popper, and many others have suggested that the (re)adoption of such a theory would resolve some of the conflicts between QM and GR.  Popper went so far as to say QM "falsified" SR.

 

Problem is general relativity is very accurate on a lot of things, and a lot of people believe in it, and GR is based on SR isn't it ?



#34 Flummoxed

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Posted 07 April 2019 - 04:17 AM

Well they hid the results for years and years. Why? And I myself have examined experiment results and found them to be much less precise then what they claim. For instance the Planck constant is only good up to 6.62607'ish, but they give a value of 6.62607001. And that is just crazy talk. I find the same discrepancies in the electron mass, and other constants. Maybe there is something to the professors claim? I kinda think there is. It's an interesting topic, thanks for responding! :)

 

Why not sart a NEW topic on it, if you want to discuss what you think are discrepancies  :)  It might just measurements are getting more accurate. Apparently the gluon field gives ~99%ish of the mass to neutrons and protons not the quark masses alone https://en.wikipedia...e_of_properties