Thank you for sharing your experiences. I fully agree with your statement.
It just feels strange that Hirata's paper was used as lecture notes of a GR class that he taught in 2012 at the Caltech. So a lot of students got this and used it for their study. Surely they must be the most critical...
Hi Paul ! Thanks for taking the time to give your feedback.
Personally I don't think there is an issue with the Lorenz gauge.
The only condition that a coordinate transformation needs to satisfy to remain within the Lorenz gauge is the wave equation (as explained in wikipedia ...
Thank you for confirming. That's too bad then, because it means that the calculation of the vector product at the end of the paper showing that the wave is transversal does not produce 0 :
The last 2 terms, both negative in the paper text, will then turn out to be positive, and cause the...
I read Chris Hirata's paper on gravitational waves (http://www.tapir.caltech.edu/~chirata/ph236/lec10.pdf) where he performs a multipole expansion of the gravitational source.
I got most of it, apart from the part where he expands the inverse distance function into a series :
More specifically...