- #1
robousy
- 334
- 1
Ok - so essentially the Feynman propogator is a Green function solved for a point source - i.e a delta function in 3 dims.
My question is more mathematical.
When you solve for the Green Function you assume
(id-m)G(x,x') = delta(x-x') (roughly)
Then solving this going through the standard process (Fourier Transforming RHS, performing integral etc) you come up with the Green function aka the Feynman propogator.
Now my question is this:
What is the original justification (for ALL Green function proplems actually) that the RHS is a delta function?? Why/How do you assume this and what is the physics meaning??
My question is more mathematical.
When you solve for the Green Function you assume
(id-m)G(x,x') = delta(x-x') (roughly)
Then solving this going through the standard process (Fourier Transforming RHS, performing integral etc) you come up with the Green function aka the Feynman propogator.
Now my question is this:
What is the original justification (for ALL Green function proplems actually) that the RHS is a delta function?? Why/How do you assume this and what is the physics meaning??