Hi All, I am trying to understand the directional independence of LT. In contrast, we all know that Doppler Effect is dependent on the direction of motion. I have tried to find any reasoning or explanation and could not find one so far. May be I did not use correct terms in my searches. If anyone can explain or point to any existing explanation(s), that will be great. I would like to clarify that V**2 is not an explanation; the "directional independence" is same as that Math term. I am looking to find any existing explanation(s) beyond that. If no other explanation exists, I have to take that as the answer! If it has been discussed before and I missed, I apologize for that. Thanks.