Recent content by Dale

Excellent, I am glad I could help

I am not so pessimistic about @Foretranimal because of their openness here. There is quite a bit to do, but they do not seem resistant to learning. I think that willingness to learn is probably more important than having mostly correct concepts to begin with.

Length contraction is the comparison of a length in a frame where it is at rest vs the length in a frame where it is not at rest. Light is not at rest in any frame, so the length contraction formula cannot apply to light. This is one reason why I recommend new students of relativity not use the...

By conflicting claims I am talking about your OP. These are indeed genuinely conflicting claims. But the thing is that they are not merely different “perspectives” (coordinate charts). They are different spacetimes (manifolds). In a spacetime where one statement holds, the other does not. Here...

Yes. Coordinates are optionally added to a manifold, but only in a manner in which all coordinates can be used to write the laws of physics and predict the outcome of experiments.

Valid is a fine word. If you want to go beyond valid then a more clear description is that the principle of general covariance says that all “perspectives” agree on the laws of physics and the result of applying them to any given experiment. I agree. There is no universal “now”. Causality is...

The standard Schwarzschild coordinates that you refer to in the second statement are on a different manifold than the Hawking spacetime for the first statement. The equivalence principle does not say your perspective is valid. The principle of general covariance says your “perspective” is valid...

That is good work. It is much more difficult to do than it appears at first glance.

I don’t think this is correct.

Indeed, if I am reading my notebook correctly the Lagrangian for a free particle in an Anderson synchronized frame is $$L=-(\dot T+(\kappa-1)\dot X)(\dot T +(\kappa+1)\dot X)+\dot Y^2 + \dot Z^2$$ This leads to a conserved energy $$E=\frac{m(1+V_X...

I hadn’t seen that, but it is a good quote. It also helps that it is clear that physics depends not only on positions but also on velocities/momenta. So it is natural that our mathematical model will contain both positions and velocities at a pretty basic level in the model.

Why would you do it without recourse to parallel transport?

There is disagreement in the literature on this point. But I tend to agree with you. Anderson, in contrast, does not restrict his ##\kappa## to be less than 1.

Unfortunately, that means the topic is not suitable for this forum. We exclusively focus on topics that are in the literature. We could discuss EFT’s in general, but not the specific topic of applying EFT’s in ways that are not established in the professional scientific literature

I see where you are coming from, but I think that usually EFT's are considered in the context of renormalization groups etc. I don't believe that those would be fruitful in EM, at least I haven't worked on an EM problem where I wanted to use such techniques. Maybe they would be useful for point...