Skip to main content

All Questions

11 votes
1 answer
1k views

Why use Crank-Nicolson over Matrix Exponential when solving Schrödinger's equation?

For Schrödinger's equation, $$\psi(x,t+\Delta t)=e^{-i H\Delta t}\psi(x,t)\approx\frac{1-\frac{1}{2}i H\Delta t}{1+\frac{1}{2}i H\Delta t}\psi(x,t).$$ The right-most expression is the Crank-Nicolson ...
XYZT's user avatar
  • 779
0 votes
0 answers
286 views

Finding the initial state in the power method for Hamiltonian diagonalization

In section III of the lecture note Chapter 1: Exact Diagonalization, Weimer has described the Power method for Hamiltonian diagonalization. The process requires the choice of an random initial state ...
Omar Shehab's user avatar
2 votes
1 answer
342 views

Can I state that $\Psi (x_1, \dots , x_n,t)= \sum_{i=1}^n a_i \psi (x_i,t) $ via superposition?

Given that the hamiltonian $\hat H$ of a system is a linear operator and $\dot \psi (x_i,t)$ does not depend on spatial coordinates $x_1, ..., x_n$ with bases $\hat e_1, ... , \hat e_n$ can I state ...
bolzano's user avatar
  • 196