The Laws Of Cosmology May Need A Re-Write?

Errr, what do you suggest is going to happen in the universe in trillions of years that looks any different than what's happening for the last twelve billion? All the galaxy clusters are going to get further and further apart. IDGI.

 

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There is no such thing as certainty that a scientific theory is true. So it cannot grow too. Another question is that the conviction that it works as a reasonable approximation will increase with time once it works nicely as an approximation.

"Near certain" sounds nonsensical. "Has a good accuracy" would be more appropriate.

And, no, this is not "just as", because for the principles of quantum theory there is no known domain of applicability. Quantum theory has a classical limit, thus, it can be used in the classical domain too. Even if it is not, given that in the classical domain the classical approximation, which is much easier to compute, is preferred, it could be used as well, and therefore the classical domain is not outside its "domain of applicability".

 

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There exists theories of gravity with a cyclic universe.

One would not even have to modify the theory of gravity for this. Replace the actual cosmological SM with Wiltshire's timescape cosmology (which uses the same GR, only with $\Lambda=0$). Then, introduce there a much smaller $\Lambda$ with the opposite sign. This would, then, later, maybe in trillions of years, stop the expansion and turn it back.

The point was, of course, simply that we have no observational evidence about the evolution in trillions of years, only about billions. So, extending our actual theories would be speculation.

 

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Other then the theory of evolution, I have never claimed any scientific theory is true. I do see some as near certain, but please do not play semantics with that phrase.

They both seem OK with me, although with SR/GR I would add great: Another example, high precision: But again Schmelzer we are arguing on semantics.

 

Some pretty fancy statistics here, but it would all be ruined if someone double-counted some correction factor.
http://arxiv.org/abs/1604.01424

 

To use the word "correct" gives yet the wrong associations. I would suggest "accurate enough". But it is already better than "true" or "certain".

And, no, this has nothing to do with my ether theory, because the same criticism would have to be applied to those who name my ether theories "true", "certain", or "correct".

Then, of course, we are able to make predictions, by simply using the same equations. But forget about any "reliable".

The first time where we have some reasonable observational support is the period of nucleosynthesis https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis between 0.1 and 1000 seconds. This period predicts the distribution of H, deuterium, He, Li created in this period. And it has a problem with Li abundance. But, given that it makes some good predictions about H, D and He, one can say that something about this period seems already well understood and tested.

The description about what happened before is roughly the result of extrapolating without any empirical evidence to support it. One can think that this extrapolation is reliable for the hadron epoch, between $10^{-6}$ second and 1 second after the Big Bang. Because this is the domain where we have evidence about the particle physics based on the SM.

If you think you can reliably extrapolate from $10^{-6}$ s down to $10^{-43}$ s, think twice. $10^{-3}$m is what you can see with your eyes, $10^{-10}$ m is already the atomic distance, $10^{-15}$ m is around the proton radius. This is what changes by $10^{-12}$. From $10^{-6}$ s down to $10^{-43}$ s we have three such factors.

 

I didn't use the word reliably. I said reasonably, reasonably speculative if you like.
The point is knowing what we already know, we can speculate reasonably back to around t+10-43 seconds.
Around that time the four forces existed as one "Superforce," that as the universe expanded and pressures and temperatures dropped, this superforce decoupled into the four forces we know today, gravity being first.
At this epoch, or thereabouts, temperatures and pressures were such that matter did not exist.
As phase transitions and false vacuums took hold, it enable energy excesses to
create our first fundamentals........Data re this period and shorlty following, is gained by scientists today, smashing particles in a particle accelerator and studying the tracks. As the Universe cooled, these particles combined to form protons and neutrons, which later joined to form the nuclei of atoms.
This is thought to have occurred in the first three minutes.
380,000 years later temperatures were such that electrons were able to couple to atomic nuclei: From there it was plain sailing.
This is a reasonable speculative mainstream picture of how it all came to be.
Like I said, the closer to the BB, the less certainty...the further from the BB, the more certainty.
You may not agree with that, but that's basically and roughly the story.
Unless you have a better picture that more reasonably and logically gives us an insight as to what happened.

 

Ok, you have a point here. Speculation, in form of extrapolation of existing theories beyond the domain where we have any empirical evidence, is indeed reasonable.

But here I have to disagree. We have, as an established theory, a theory we already know, the Standard Model of particle physics. But theories about a Superforce are theories beyond the SM. So, this is nothing we already know. This is speculation only. Even if this particular speculation may be popular.

What we obtain today in particle accelerators is all covered by the SM. And below the "electroweak phase transition", which one can reasonably believe if one believes the SM, but which is nonetheless only theoretical speculation yet.

The point is not who has the most beautiful picture. The point is to distinguish between regions where we have empirical evidence in favor of a theory, regions where we simply extrapolate theories which are supported by empirical evidence, and regions where we have to use even theories which are purely speculative, without own independent empirical support.

BTW: What is your problem with discussing semantics? I think to discuss semantics https://en.wikipedia.org/wiki/Semantics and to correct semantical errors is important.

 

Good point. Thanks for explaining your thinking.

 

It is based on what we do know though, and that's the reason it is popular:

I do use the phrases "near infinite" and "near certain" and by applying semantics one could as you say, class them as nonsense.
But just as obviously any logical human should know what idea is really meant to be conveyed with such phrases. eg: I often say the universe is "near infinite" in extent and content, meaning that it is so humongously big as to be beyond any human comprehension.
Of course if it is not "near infinite" it is certainly infinite if you know what I mean. In other words for someone [and I'm not referring to you in this case] to grab hold of the semantics of those phrases and run with them, are most likely just avoiding the real issues at hand.

Schmelzer, I know what speculate means, and agree that what mainstream scientists propose did and will happen is speculation.
But it is not just speculation that they drag out of their rear end: It mostly has some reference to present knowledge.

 

You should more correctly say it is "at least near infinite." Perhaps that will help you two work through your semantics.

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wrong bloody thread!

 

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What I'm really trying to say in even more basic language, is that certainly cosmology certainly still has a long way to go to achieve [if achievable] the positive results that Schmelzer is on about. No argument. But the fact that they are even able to make "educated guesses," on questions such as "how can we have something from nothing," or the Universe being the "ultimate free lunch," as well as the reasonable predictions already mentioned, means we have come a long way and can be reasonably pleased with ourselves. [ourselves being humanity in general]
In the distant past, to even ask such questions, got nothing more then blank looks, or the invoking of mythical deities, spaghetti monsters, magical Unicorns and such.

 

No. GUTs are simply speculations. Not based on anything but a nice dream how a final theory could look like. Made compatible with the SM, that's all.

I have an idea what you could mean with "near certain", and I think this is simply wrong. That's why I object.
I also have an idea what you could mean with "certainly infinite", and I think this is wrong too. Simply because it is not at all impossible to develop a viable theory with a very large but finite number of degrees of freedom.

In the same way as my ether theories have some reference to present knowledge. (Not exactly the same way, my ether theories have a much closer reference to present knowledge. http://www.sciforums.com/threads/an-ether-theory-of-gravity-compatible-with-modern-physics.153203/ gives the Einstein equations in a natural limit, and http://www.sciforums.com/threads/an...he-standard-model-of-particle-physics.153207/ the fermions and the gauge group of the SM.)

I would disagree here. Except if one interprets the quotation marks around the "educated guesses" in a pejorative way.

 

Once again going past your usual semantics, your first statement I totally reject with regards to your claim a GUT is not based on anything, and your ether hypothesis in no way resembles what I'm saying and what you are dismissing: We already have GR explaining gravity and the cosmos in a fashion that has had overwhelming confirmation of late. No ether is needed. [But please, let's not get into that again

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GUT of course, is based on Maxwell's unifying of electric and magnetic
forces as far back as the 19th century.

Would you?

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That's OK, you're entitled to your opinion, but I believe I have pretty much told it as it is.

 

My remark was not at all about GR. The Einstein equations of GR have sufficient empirical support, I have not questioned this. The reason why I have rejected some of your speculations as speculation was that they, together with assuming GR, have also assumed theories about matter far beyond the SM.

You have a simple method to avoid responses defending the ether: Not making false claims against the ether. Once you don't use this possibility, don't whine.

The problem of quantization of GR is unsolved since the creation of quantum theory. How to quantize a condensed matter theory in Newtonian spacetime is, instead, well-known. So, quantization of an ether theory of gravity is not even a problem.

No. Ok, you can say that GUT is based on the vague idea that unifications of different forces are a good idea. And Maxwell's theory of unifying electricity and magnetism was a historical example that this vague idea worked nicely. That's all.

This has been discussed elsewhere, and I'm too lazy to repeat myself. Ok, short summary:

You need, of course, some basic physics education to understand the first parts of the following transformations:

GR has a big problem that it has a big bang singularity --> GR describes how the universe is created out of nothing, greaaat!
GR has a big problem that it has no adequate local energy-momentum conservation laws --> GR describes how we can have the ultimate free lunch not restricted by conservation laws, juchheee!

But this does not make nor the transformations, nor the result educated guesses in any reasonable understanding of this phrase.

 

You are not rejecting any of my speculation, you reject generally mainstream speculation, based on what we already know.

I have not made any false claims in this thread about the ether: Obviously it is unecesary and superfluous and has yet to be cited.
Mainstream in general reject such a theory.

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Yes, GUT certainly does have past accepted mainstream examples to support such speculation as I have said.
https://en.wikipedia.org/wiki/Grand_Unified_Theory
Grand Unification is reminiscent of the unification of electric and magnetic forces by Maxwell's theory of electromagnetism in the 19th century, but its physical implications and mathematical structure are qualitatively different.
https://en.wikipedia.org/wiki/Grand_Unified_Theory

Yet you do:

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But I'm really not interested in reading again some fabricated excuse to basically add credibility to a superfluous ether hypothetical by deriding GR and the BB.
On your little crack at me re needing education, sure! And I'll certainly keep getting that from reliable, respected, reputable quarters.
My claims that reasonable speculation and educated guesses based on current knowledge and data stand.

 

No it hasn't.

The frozen star description comes from GR.

When you read the Einstein digital papers you understand what a gravitational field is, then you understand that the frozen-star description is the right description and the point-singularity description is wrong. Because light can't go slower than stopped. Then you flip it around and there's no point-singularity in your early universe, just homogeneous "frozen star space". So you don't need inflation to smooth it out.

I'm just here to talk physics. Now follow my references and read the Einstein digital papers and other material instead of clinging to some pop-science ersatz version of GR peddled by self-promoting quacks who appeal to Einstein's authority but flatly contradict the guy. Make sure you read Ether and the Theory of Relativity, then you can apologise to Schmelzer.

 

Naively applied GRT having a singularity doesn't preclude a more sophisticated approach (i.e. inflation) that also uses GRT cleaning up that as well as some of the other problems (domain walls, isotropy and flatness, size of the density fluctuations indicated in the CMB vs. size of the predicted density fluctuations in the Big Bang) that the naive approach appears to lead to. Inflation isn't accepted by mainstream cosmology for nothing. And as far as creating a universe from nothing, it doesn't do that; that requires QM (vacuum fluctuations) as well.

As long as you stay in a consistent frame, GRT preserves energy and momentum conservation laws. It's only when one (erroneously) attempts to transport values from one frame to another without transforming them that energy and momentum aren't conserved. As far as the universe not obeying energy conservation, the idea is that the total energy of the universe is zero. If it's zero, then there's nothing to violate conservation; started at zero, is zero now, will be zero for the foreseeable future. I'd like to see your justification for claiming that GRT doesn't conserve energy and momentum. I suspect I'll rather quickly find where a proper transform from one frame to another isn't being done correctly; I've seen a lot of claims like this and been able to find that place rather quickly in every case so far.

 

Pulling out of context quotes from Einstein's papers is not doing physics. Why won't you take some courses and learn something instead of making baseless statements and wasting everyones time?