This was vaguely discussed in another post, but unsatisfactorily in my oppinion. (http://www.sciencefo...ffect-is-right/)

I read the article on mass in special relativity, and it discusses transverse and longitudinal mass. https://en.wikipedia...ngitudinal_mass

My question is this, why is it a power of 3 for parallel to the direction of the velocity and a power of 1 for the perpendicular velocities, ie:

fx = m . γ^3 . ax = mL . ax

fy = m . γ . ay = mT . ay

fz = m . γ . az = mT . az

I've always been taught that relativistic mass is:

m = m0/γ

Thanks for any explanation in advance.

The reason I'm asking is that I found that gravitation expands itself with a power of 3 and might relate to longitudinal mass, but it's unclear how it relates until I understand why they're using a power of 3 above. Here's the theory that includes power 3 for gravity:http://www.sciencefo...-of-the-forces/

**Edited by devin553344, 05 July 2020 - 02:12 PM.**