pervect's latest activity

One of the early steps, though perhaps not the very first, would be to pick a textbook appropriate to your background. It's...

First, some background. Sorry, it's a bit long. I've been considering the orbits of photons around a black hole. First some...

I had to look this up. My source is not the best, but it says the indices in h_ab do run from 0..3. I'm not sure if I actually said...

The two formal defintions of born rigidity I'm aware of apply to timelike congruence which I will denote as ##u^a##. I believe the...

I don't understand the reference to "trying to turn into a torus", but I did find references (and also had vague recollections that I...

Do you have a reference? I was unable to confirm, though I did run into some interesting reading about bar mode instabilities for a...

To understand the rotating disk in special relativity, I believe you need some background material that is not high school level. The...

That's a good comment, it might be worth mentioning a list of commonly used coordinate time standards besides cosmological time. The...

Some recent threads inspired me to want to make a list of the different notions of time we need in physics (As I write this, I am...

The organizational structure in MTW actually illustrates why there are 20 degrees of freedom and 21 unique (up to sign) nonzero...

I was doing some more reading, and apparently the "modern" approach to the topic involves decomposing the Weyl tensor rather than the...

It seems to me you are asking, at least in in part, about the self-force problem. "How does a particle, the thing that you are calling...

There is a way to break down, or decompose, the curvature tensor in General relativity (called the Riemann tensor) into parts, which can...

If you do an experiment in a small sealed box where you only look at things inside the box, the laws of physics according to special...

I'm on board with this - I regard it as the theory of timelike congruences, which I first stumbled across in Wald, and later read more...