Parity operator commutes with second derivative?

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SUMMARY

The discussion focuses on proving that the parity operator, defined as Af(x) = f(-x), commutes with the second derivative operator. The user presents an initial approach using the notation A∂²f(x)/∂x² and simplifies it to show that ∂²Af(x)/∂x² equals ∂²f(-x)/∂x². The conclusion drawn is that the parity operator and the second derivative operator can indeed be applied interchangeably without altering the outcome, confirming their commutation.

PREREQUISITES
  • Understanding of differential operators, specifically second derivatives.
  • Familiarity with the concept of parity in mathematical functions.
  • Knowledge of notation used in calculus and functional analysis.
  • Basic principles of operator theory in quantum mechanics.
NEXT STEPS
  • Study the properties of linear operators in functional analysis.
  • Explore the implications of commutation relations in quantum mechanics.
  • Learn about symmetry operations and their applications in physics.
  • Investigate the role of parity in solving differential equations.
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Mathematicians, physicists, and students studying quantum mechanics or advanced calculus who are interested in operator theory and symmetry properties of functions.

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How do I prove that the parity operator Af(x) = f(-x) commutes with the second derivative operator. I am tempted to write:

A∂^2f(x)/∂x^2 = ∂^2f(-x)/∂(-x)^2 = ∂^2f(-x)/∂x^2 = ∂^2Af(x)/∂x^2

But that looks to be abuse of notation..
 
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You can do both differentiations separately, then it does not look so bad any more.
 

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