PeterDonis's latest activity

More precisely, by the Riemann curvature tensor that's derived from a metric via its Levi-Civita connection. There's no problem with...

If the paper is "hovering" statically, i.e., no radial or tangential motion, frame dragging has no effect.

The paper cited in the OP makes heavy use of the DESI 2025 release. Statistical analysis is in section 4.

Basically, yes. Not from cosmology, no. If I understand the paper correctly, revising our model of the universe in the way the paper...

Yes, one possible result if this new analysis holds up is that cosmologists would revise their estimate of the value of the cosmological...

Ok, so your "therefore" should not have been there.

It is, provided that our universe's cosmological constant actually is positive.

Yes. I'm not sure where your "therefore" here comes from; this statement is completely unrelated to the previous one. There's no...

Yes, there are theoretical models that do that. If there is no dark energy (zero cosmological constant), then the only significant...

Of course that's wrong. The Einstein Field Equation works just fine with a positive, zero, or negative cosmological constant. All models...

Not. Even if it turns out that there is no dark energy and the expansion of the universe is not accelerating, that doesn't mean the...

Where? Please give a link to the specific thread.

I marked this thread as "A" level for a reason. You've gotten some good general responses, but be aware that you might not be able to...

We use Type 1a supernovae to estimate distances because how bright they are is well correlated with various other characteristics like...

Yes it does, because a tetrad by definition has four mutually orthogonal vectors.