Recent content by Kamikaze_951

Hi dextercioby, Thank you a lot for your reply, that was exactly what I needed. I did the calculation with that in mind and it worked. In fact, I am ashamed not having seen this by myself.

Homework Statement To whom it may concern, I am trying to understand the central force problem of the Dirac equation. In particular, I am following Sakurai's Advanced Quantum Mechanics book. There (section 3.8, p.122), it is shown that there is an operator K = \beta(\Sigma . L +...

Hi everyone, I would like to know if the energy of each body of a two body gravitationnal problem is separately conserved. I know that the individual angular momentum are separately conserved and that the TOTAL energy of the two bodies is conserved. However, I don't know if there could be...

Hi clamtrox, I thank you a lot for your reply. It doesn't solve my problem, but it allows me to clarify what I am trying to do. We can compute R_{\mu\nu} easily once we know that the FRW metric applies. However, it is the energy-momentum tensor that I am looking for (i.e. I have to work...

Hi everyone, It's not a real homework problem, but something I am trying to do that I haven't found in the literature. I am still stating the problem as if it was a homework Homework Statement Consider a FRW Universe. That is, ℝ x M, where M is a maximally symmetric 3-manifold, with a RW...

Your post just made me realize that I considered the wrong system (Sun+mass rather than Sun+Earth) and forgot to take into account the energy transfer between two masses of the same system. Your answer was very helpful and I thank you a lot for it.

Hi everyone, This is my first post here and I am really sorry for that question, but I have found the answer nowhere. Consider a mass at the Earth's equator that is static in the Earth's referential during an entire day. Put the Earth at one of its equinoxes to simplify the problem. Then...