Quantum mechanical expectation value

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SUMMARY

The discussion centers on calculating the expectation value of the momentum squared (p^2) for the harmonic oscillator ground state in quantum mechanics. The integral involves the second derivative of a Gaussian function, specifically an exponential of a negative squared term. The solution reveals that the integral simplifies to an x^2 term multiplied by exp(-x^2), and the key insight is recognizing that the second term is a derivative of a Gaussian function. This understanding resolves the initial confusion regarding the integration process.

PREREQUISITES
  • Understanding of quantum mechanics principles, particularly harmonic oscillators.
  • Familiarity with Gaussian functions and their properties.
  • Knowledge of integration techniques, including integration by parts.
  • Basic proficiency in calculus, specifically dealing with derivatives and integrals of exponential functions.
NEXT STEPS
  • Study the properties of Gaussian functions in quantum mechanics.
  • Learn about the harmonic oscillator model in quantum physics.
  • Explore advanced integration techniques, particularly in the context of quantum mechanics.
  • Investigate the role of expectation values in quantum mechanics and their applications.
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Students and professionals in physics, particularly those focusing on quantum mechanics, as well as anyone interested in advanced calculus and mathematical physics applications.

Master J
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I'm trying to calculate the expectation value of the momentum squared (p^2) of the harmonic oscillator ground state.

The integral involves the second derivative of a Gaussian (exponential of a negative squared term)

Then the integral involves, after working it out, an x^2 term times exp(-x^2).

I tried this by integrating by parts but it gets me no where. Am I missing something?
 
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Wait, I solved it :p


If anyone is interestes, it's just the fact that the 2nd term is a derivative of a Gaussian!
 

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