Recent content by DerHutmacher

Hi all, I finally understood what is happening. So no residue is taken, but after the deformation of the contour, for every point of the path left to the branch cut, one subtracts the value of the horizontal point right to the branch cut. Because of the branch cut, this value is the same, if we...

Thank you for the quick answer but I still do not quite understand what we are doing to finally evaluate the integral? After we showed that our former integral is equal to the contour integral that is attached in the file, I would still not know what I should do, to get any value from the...

Hello all, I have a additional question to this topic ( I don't regard is at off-topic which is why I didn't open a new thread. If I'm mistaken, please correct me). In general I understand the argument made above, but I do not see, why one can use the residue theorem, since by closing the...

Hello everyone, for quite some time I am struggling with the following question: If we consider the action for a single particle in Classical Electrodynamics $$S[x(\tau),A(x)]=\int - m\ ds - \int d^4x\ A_{\mu}(x)j^{\mu}(x) -\frac{1}{4}\int d^4x F^{\mu\nu}(x)F_{\mu\nu}(x) $$ with $$ds=...