What is the Solution for Canceling Out Terms in QM Calculation?

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Homework Help Overview

The discussion revolves around a quantum mechanics calculation involving the cancellation of terms in the context of the Schrödinger equation. Participants are exploring the implications of different terms and their roles in the calculation.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the possibility of canceling terms and the conditions under which this might occur. Questions are raised about the correctness of the Schrödinger equation as presented, and the need for adjustments in the calculation is noted. There are also references to integration techniques and their effects on the terms involved.

Discussion Status

The discussion is active, with participants offering various insights and suggestions regarding the calculation. Some guidance on integration techniques has been provided, and there is an exploration of potential adjustments needed for the Schrödinger equation. Multiple interpretations of the problem are being considered.

Contextual Notes

There is mention of a specific textbook, "Introduction to QM" by Griffiths, which may contain relevant calculations, though its applicability is uncertain. Participants are also questioning the assumptions made regarding the terms in the equation.

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Homework Statement



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Homework Equations


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3. The Attempt at a Solution
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I almost get the answer as long as I can cancel out the first 2 terms.
But they are different, what can I do now?
 

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now you do the integral
 
Isn't there supposed to be a minus in the Schroedinger equation ? (-hbar^2 / 2m d^2 psi / dx^2)
 
the first term will cancel after 2 applications of integration by parts. the second term will need some adjustment with Schrödinger equation and cancel out. at the end you end up with a term thatll look like the potential energy only from the Schrödinger equation.
 
i believe you can find the direct calculation on introduction to QM by griffiths, not certain though
 

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