Recent content by KariK

Well, nobody responded to this question and some time ago I understood the issue, so here is the answer for posterity. If you solve the Klein-Gordon equation for a scalar field, the answer depends on the phase: Phi = ...*e^(i*k.x)*..., where k is a constant and x is the comoving coordinate. We...

I am studying particle pair production using Parker and Toms book: Quantum Field Theory in Curved Spacetime. On page 48 they talk about converting the sum over momentum (k) into an integral. You assume boundary conditions so that k = 2*Pi*n/L, where n is an integer and L is the coordinate...

Thank you jedishrfu for moving this thread to a more appropriate place. While I got the Bessel equation from physics, the topic is indeed more math than physics. And thank you Paul Colby for confirming my assumptions.

In Wikipedia article on Bessel functions there is an integral definition of “non-integer order” a (“alpha”). For imaginary order ia I get that Jia* = J-ia, where * is complex conjugate and ia and -ia are subscripts. Then in same article there is a definition of Neumann function, again for...