Chinese Scholar Yang Jian liang Putting Wrongs to Rights in Astrophysics

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note that though the state p=-d had been put forward for long time, the origin is different from Yang's that. Yang don't need any assumption and the p=-d directly worked out of field equation according to the requirement of metric, and on Wiki, p=-d is other an assumption. Therefore, Yang's scheme is more logical and the calculation results are more reliable

 

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Obviously, dark energy is not exotic matter: look at the name. Perhaps you should learn what (dark) energy is?

Why is it that you are having such problems with the basics of GR and cosmology? I thought you'd spend years and years on this?

Dark matter is much less exotic than your proposed type of matter. Additionally, there's a lot of evidence for dark matter already; I think I linked the Wikipedia-article before in this thread; have a look at it!

And it's not that I oppose all types of exotic matter; that's a strawman. I oppose the concept of matter so exotic it can't reasonably be called matter anymore.

So... Yang introduces dark energy to replace the cosmological constant, something that is already done in standard cosmology for years? Well, if that's on the order of the biggest discovery Yang made, his work is pretty much worthless.

Is it? Evidence please!

The earth is made out of dark energy? What?

Not really; it'll be similar to what GR and cosmology did for us.

False; it's not an assumption in cosmology either. Please learn what GR and cosmology actually say about the matter (pun intended!) before making such ridiculous claims!

That argument only holds if both have more-or-less the same amount of explanatory power (Occam's Razor). You have yet to demonstrate this.

 

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but it is ext

dark energy isn't exotic matter, but it is exotic thing, in a word it is not ordinary

 

Right, exactly. Glad you agree on my answer to that question you asked in post #439. I'm glad I could teach you something.

 

on Wiki, state equation is writen as p=kd, the k is a uncertain const, they used k=-1 tentatively and cann 't be sure k=-1, therefore say p=-d is a assumption on Wiki, and Yang's p=-d is an exact solution.

 

It's an exact result? Great, let's see the evidence to support that claim!

 

1

 

so far haven't you seen the evidence yet? I say again, in the process of solving the metric of spherically symmetric weak field the coupling coefficient is confirmed for 4paiG and by the way the pressure in body is solved for p=-d, obviously Yang's theory is more plain

 

You clearly have no idea how science works. In science, your hypothesis must be supported by observational evidence before you can claim it's correct. Show the observational evidence that demonstrates that Yang is right (and that the usual EFE is wrong). This is why I asked if Yang's theory can model the Cl's of the CMB (which it apparently can't; at least, you couldn't point me to it); that's observational data that would need to be explained by Yang's model in order to replace the current paradigm, because the current combination of GR and cosmology can explain these features of the CMB quite well.

Edit: Oh, also, the universe is not spherically symmetric, nor purely weak field. So even if Yang's model works in such a case, that doesn't help you prove it works for our universe.

 

yes, it is because Yang's work completely consists essentially with observations that I say that there are many evidences to support Yang. the most important observations are the distances and reshifts of remote celestial bodies, the new relation between distance and reshift calculated using the modified field equation completely satisfies the data. Such consistency strongly indicates Yang's modification is successful. Before, the distance redshift relation derived from the old field equation was in serious contradiction with the observational data. In order to eliminate the contradiction, cosmologists artificially added the cosmological constant, which is actually adding new assumptions, and not really solving the contradicition. the cause to say cosmological constant is new assumption is that in solar system don't need cosmological constant, that is to say, cosmological constant is not verified in solar system, no reason used in whole universe. Moreover, cosmological const cann't make geodesic equations back to Newton law in the spherical symmetric weak gravitational field, indeed it makes serious logic crisis, therefor cosmological constant must be thrown away. Besides, Yang's modification fully qualifies to explain this CMB, and more natural. See Yang's discussion

 

Cosmologists often say that standard models explain a lot of observations, but most of them are far-fetched, or like a patchwork catered to observational data. No prophecy is a corollary of the standard model because there are too many uncertain parameters in the standard model, such as dark matter, dark energy, cosmic pressure, cosmological constant, and so on, besides, there are some odd artificial assumptions, such as unflation that is impossible to verify. Only Yang's new model is solid and really faces the world. again, the old theory cann't explain the earth's expansion, the solar system's expansion, as well as why the sun is bright and bright. It is Yang's work that links the observed rule for mass-luminosity ratio to the growth of celestial bodies, how profound this is! how powerful this logical system is!

 

No, you need to explain how two quite different things, one is the derivative of the other, become the same thing because of natural units.

Energy density = Joules per unit volume E/v ; Pressure = dE/dv. A body in thermal equilibrium has the same pressure and energy density everywhere. This is very obviously not the case in the present universe.

 

They are physically not the same thing but....read from Abstract down to just below eqn (1.4) here: https://arxiv.org/abs/gr-qc/0510041
There are some paradoxical issues associated with pressure as a source of gravity, but that's another story.
On the very large cosmological scale considered, pressure (assuming DE as a physical uniform negative pressure is true) and (matter + radiation) density average out to both being effectively uniform.

 

yes

 

Gave arfa brane a like for criticizing your use of pressure and density together? Interesting.

 

in natural unit, light's speed c=1 , thus the unit of pressure is the aame as density, see any textbooks

 

And you are addressing that to me not the poster of #453? Why? Unless you quote each time in responding, confusion results. To whom was that 'yes' in #455 addressed to?

 

I think the best anyone can say about pressure and density being "the same" in the real world is when you mean in a gas at a constant temperature at all points. Like I say above, that says nothing about the state of the current universe. This universe isn't in a state of equilibrium.

 

That's not the issue you took exception with, which was one of dimensionality, addressed in that article linked to in #454. Evidently ignored entirely.

Doesn't have to be. Large scale homogeneity of matter is quite compatible with an expanding even accelerated expansion universe. Cosmological principle.
And now I wait for some disjoint response from the other poster of late - addressed to someone, or maybe no-one....