Recent content by coki2000

But in the larmor precession case, eigenvectors of the hamiltonian is all time-independent. How can I know the before and after wave functions. Before and after time t' wave functions are same.

Yes I understand your point. But problem says that we apply an instantaneous magnetic field in x direction on the precessing particle at time t'. I tried to solve this like the dirac-delta potential problem but it is different I think. Because in this case I cannot find a time dependent wave...

Any ideas?

Yes, they are dirac-delta functions. Those dirac-deltas stand there for representing a magnetic field pulse in x direction at t = t'

Any advice :(

Hi PF members, I am stuck with a problem about larmor precession. I cannot find the eigenstates of the hamiltonian given as H = \frac{\hbar}{2}\begin{pmatrix} \omega_{0} & \omega_{1}\delta(t-t') \\ \omega_{1}\delta(t-t') & \omega_{0} \end{pmatrix} Can anyone help me? Since it has time...

Hello PF members, I am trying to solve for helium atom ground state by using perturbation theory. It is very easy to calculate the first order correction of ground state energy but I have no idea for how to find its wave function. I have tried to use the first order correction formula for wave...

In a question, I am given that electric field is constant and a lagrangian which includes a term with A. So how can choose A in this problem?

Hi PF members, I have a question about how to find the vector potential from a given electric field. For example, \textbf{E}=-\nabla\phi-\partial\textbf{A}/\partial t and \textbf{B}=∇\times\textbf{A} Given \textbf{E}=E_{0}\hat{x}, electrostatic potential may be 0 and...

Thank you very much for your help :)

Thank you for your response. But in the definition of the elliptic integral, we have the square of sine in the square root. In my case it is not square of the k*sinx.

Mathematica gives a solution with an elliptic integral but since my operation interval does not require any imaginary part, it is not useful for me. http://www.wolframalpha.com/input/?i=int%5Bsqrt%7B1+-+2sin%28x%29%7Ddx%5D So I need another and simpler solution.

Hello PF members, I want to solve this integral but I cannot find a method. \int\sqrt{1 - 2sin(x)}dx for 0 < x < ∏/6 Or more generally \int\sqrt{a - bsin(x)}dx for a > b How can I solve this? Thanks in advance

Thank you very much. I will search for it.

Very enlightening explanation, thank you for it. :) But current flows in the wire must be infinite since there is no resistance, right? Therefore the magnitude of electromagnetic wave also must be infinite. Doesn't it reduce the whole energy immediately?