Jaime Rudas's latest activity
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Jaime Rudas reacted to PAllen's post in the thread I The quintessence as variable dark energy with
Informative.
That is an exceedingly narrow statement of the equivalence principle. The most commonly accepted meaning of strong equivalence principle... -
Jaime Rudas reacted to PAllen's post in the thread I The quintessence as variable dark energy with
Like.
While the FLRW metric, when used for a realistic universe, is purely an emergent approximation at large scales, there is one aspect of... -
Jaime Rudas reacted to PeroK's post in the thread I The quintessence as variable dark energy with Like.
There are no voids in a homogeneous universe. If you want to study a local region of the universe, then you need to set up the...
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Jaime Rudas reacted to PAllen's post in the thread I The quintessence as variable dark energy with Informative.
Yeah, but if you are talking about galaxies, you are outside the FLRW idealized model - that has only perfect fluid with different...
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Jaime Rudas reacted to PAllen's post in the thread I The quintessence as variable dark energy with Like.
As far as I know, the common models of quintessence still use the FLRW equation metric, just with particular forms of ##a(t)##. In...
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Jaime Rudas reacted to PeterDonis's post in the thread I The quintessence as variable dark energy with Like.
"Space" isn't an invariant. It varies in spacetime. Whether that means variation in "space" depends on your choice of coordinates...
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Wikipedia says: Does the quintessence really vary in space? Wouldn't that imply violating the cosmological principle? Or perhaps it...
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Jaime Rudas reacted to PeterDonis's post in the thread A Couldn't the cosmological constant also have some sort of "dynamics"? with Like.
It's straightforward to write down the model; indeed doing that is an exercise in some advanced GR textbooks. The usual way is to use a...
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Jaime Rudas reacted to PeterDonis's post in the thread A Couldn't the cosmological constant also have some sort of "dynamics"? with Like.
Because a constant is the simplest model, and we have no evidence that it's not constant, so we use the simplest model that's consistent...
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Jaime Rudas replied to the thread I Euclidean geometry and gravity.Ah, yes, now I understand: its area is equal to that of a sphere of the same radius 4πR².
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Jaime Rudas replied to the thread I Euclidean geometry and gravity.In what sense the pseudo-sphere isn't "a global embedding – the complete unbounded hyperbolic plane in ##E^3##"? Is it, perhaps, because...
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Jaime Rudas reacted to PAllen's post in the thread I Euclidean geometry and gravity with Informative.
I can’t seem to let this go, partly because some have asked for how to make the embedding result (part of Euclidean plane in 3-sphere)...
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Jaime Rudas reacted to PAllen's post in the thread I Euclidean geometry and gravity with Informative.
Radius of curvature = 1
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Jaime Rudas replied to the thread I Euclidean geometry and gravity.What does "unit" mean in this context?
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Jaime Rudas replied to the thread I Euclidean geometry and gravity.Is that "flat plane" two-dimensional or three-dimensional?