Griffiths quantum harmonic oscillator derivation

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SUMMARY

The discussion focuses on Griffiths's derivation of the quantum harmonic oscillator, specifically addressing the transition from the recursion relation for large j to the equations presented in the second photo. The user seeks clarification on the derivation process and explores alternative methods to arrive at the approximate solutions. The conclusion reached is that the solution can be derived by recognizing that each subsequent term in the series is divided by j/2, leading to the factorial expression (j/2)! in the denominator, confirming c/(j/2)! as a valid solution.

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  • Understanding of quantum mechanics principles, particularly the quantum harmonic oscillator.
  • Familiarity with recursion relations in mathematical physics.
  • Knowledge of factorial notation and its application in series solutions.
  • Experience with Griffiths's "Introduction to Quantum Mechanics" textbook.
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Homework Statement



I am unsure as to a step in Griffiths's derivation of the quantum harmonic oscillator. In particular, I am wondering how he arrived at the equations at the top of the second attached photo, from the last equation (at the bottom) of the first photo (which is the recursion relation approximated for large j).

Any help?

Homework Equations


The Attempt at a Solution

 

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Substitute the approx. solution into the approx. equation. Is it satisfied?
 
Is there a way to derive the solutions besides via a fortiori means?
 
The could be some clever way, but since the exact solution is known, the approx. solution could equally have been obtained from it.

EDIT: it actually seems very simple: since for every "next" term we divide the previous by j/2, one should expect (j/2)! in the denominator, and c/(j/2)! should be fairly obvious as a possible solution.
 
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