Compute SHO Propagator: Eigenfunction Expansion

  • Context: Graduate 
  • Thread starter Thread starter chafelix
  • Start date Start date
  • Tags Tags
    Propagator Sho
Click For Summary
SUMMARY

The discussion focuses on computing the Simple Harmonic Oscillator (SHO) propagator using eigenfunction expansion. The formula presented is K(x’,x;t)=sum_ i phi_i(x’) phi_i(x) exp(-iε_it/hbar), which incorporates Hermite polynomials and generating functions. The user encounters difficulties in applying the generating function to multiple Hermite polynomials and seeks clarification on the use of the Mehler formula for this purpose. The conversation highlights the complexities of quantum mechanics calculations involving eigenfunctions and propagators.

PREREQUISITES
  • Understanding of quantum mechanics principles, particularly the Simple Harmonic Oscillator.
  • Familiarity with Hermite polynomials and their properties.
  • Knowledge of generating functions in mathematical physics.
  • Experience with the Mehler formula and its applications in quantum mechanics.
NEXT STEPS
  • Study the derivation and applications of the Mehler formula in quantum mechanics.
  • Explore the properties and applications of Hermite polynomials in quantum systems.
  • Learn about generating functions and their role in solving differential equations.
  • Investigate the mathematical techniques for computing propagators in quantum mechanics.
USEFUL FOR

Quantum physicists, graduate students in physics, and researchers working on quantum mechanics problems involving propagators and eigenfunction expansions.

chafelix
Messages
26
Reaction score
0
I know how to do SHO propagator by computing the action. I was only trying to do it
via the eigenfunction expansion
K(x’,x;t)=sum_ i phi_i(x’) phi_i(x) exp(-iε_it/hbar )=(m omega/pi*hbar)
sum_i=-^infty h_i(y’) h_i(y) exp[-(y**2+y’**2)/2] [s(t)/2]**i
with s(t)=exp(-iomega t)
This looks close, but not quite there:
I can get the 1/i! from the Hermite polynomials h_i, and I can use the generating function, but that only applies to a single h, not a product. Am I missing something along this way? I also tried substituting the expression involving (y-d/dy)**i for the h_i, but cannot get it to work
 
Physics news on Phys.org
ok, need the Mehler formula
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 6 ·
Replies
6
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 9 ·
Replies
9
Views
4K