Is This Equation for Expectation Values Correct?

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SUMMARY

The equation for expectation values discussed is confirmed as correct. Specifically, the relationship <{\psi_i |A|\psi_j}> = <{\psi_j |A^\dag |\psi_i}>^* holds true, where A is an operator, A^\dag is its Hermitian conjugate, and the asterisk denotes complex conjugation. Additionally, the scalar product relationship <{\psi_j |A^\dag |\psi_i}> <{\psi_i |A|\psi_j}> = <{\psi_i |A|\psi_j}> <{\psi_j |A^\dag |\psi_i}> is also validated.

PREREQUISITES
  • Understanding of quantum mechanics and linear algebra
  • Familiarity with operators and their properties in quantum mechanics
  • Knowledge of Hermitian operators and complex conjugation
  • Basic proficiency in bra-ket notation
NEXT STEPS
  • Study the properties of Hermitian operators in quantum mechanics
  • Learn about the implications of complex conjugation in quantum states
  • Explore the significance of expectation values in quantum mechanics
  • Investigate the role of scalar products in quantum state interactions
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Students of quantum mechanics, physicists, and anyone studying linear algebra in the context of quantum theory will benefit from this discussion.

Niles
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Homework Statement


Hi

Say I have the following number:

[tex] \left\langle {\psi _i |A|\psi _j } \right\rangle[/tex]

1) First of all, am I correct when saying that

[tex] \left\langle {\psi _i |A|\psi _j } \right\rangle = \left\langle {\psi _j |A^\dag |\psi _i } \right\rangle ^* [/tex]

where the asterix denotes complex conjugation and the dagger means Hermitian conjugate?

2) Since what we are dealing with above is just scalars, then I am correct when I say the following is true, right?

[tex] \left\langle {\psi _j |A^\dag |\psi _i } \right\rangle \left\langle {\psi _i |A|\psi _j } \right\rangle = \left\langle {\psi _i |A|\psi _j } \right\rangle \left\langle {\psi _j |A^\dag |\psi _i } \right\rangle [/tex]


Niles.
 
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