Recent content by zb23

In the spectrum of the closed string, we encountered a graviton. Why is the symmetric 2-tensor in the open string spectrum, not a graviton?

Of course, I understand, I mean I am currently doing field theory in particle physics and some arguments for plane wave solutions, for me, lack some structure, therefore I asked...I just wanted to get some more insight into some basics...

Yes, I understand that but aren't the things you said just consequences? It is like it bothers me in some fundamental QM way. I mean I can't be satisfied with the argument that it gives nice solutions. I mean, it is obviously correct considering the experiments in QM.

Yes, I agree, but still, is there some deeper meaning behind plane waves? Is it "just" most physically appropriate?

Why in order to derive the QM momentum operator we use the plane wave solution. Why later on in field theory and particle physics, the plane wave ansatz is so physically important?

What would happen with Einstein's coefficients if we wouldn't neglect the recoil effects?

Can a solid vibrate with only one frequency-Debye maximal frequency?

yes of course

is the concept of potential just a mathematical model

It doesn't matter. Sorry for bothering you.

I am not talking about those trivial stuff

Please understand my question more deeply

What is the difference on microscopic level between electric current and heat current(conduction)?

E is not a vector field that represent electric field*

I understand but E is not longer a vector field it is just an amplitude vector that doesn't have to satisfy maxwell equation.