Recent content by jsc01

I am somewhat new to tensor algebra so I am not too familiar with the contraction operation. Here is what I found from Wolfram. When T^j^i is interpreted as a matrix, the contraction is the same as the trace. Sometimes, two tensors are contracted using an upper index of one tensor and a...

Hello George, I was told that E^2-c^2B^2 and \vec{E} \cdot \vec{B} are the only Lorentz invariants composed of E and B bilinearly. Could it be that if we let \vec{E} \cdot \vec{B} = 0, which is true for an electromagnetic wave, then the binlinear form is EB which is invariant...

I believe you but how can this be proved? JSC

Hello all, this is my first post so I hope the question I have is interesting, at least to a few, and that I can learn something from the discussion. I had problem for a class not long ago in which I had to prove that: \vec{E} \cdot \vec{B} and E^2 - c^2B^2 were Lorentz invariant. I was...