Is the following operator hermitian? C|Phi> = |Phi>*

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Discussion Overview

The discussion revolves around the question of whether the operator defined by C|Phi> = |Phi>* is hermitian. The context is mathematical, specifically within quantum mechanics, as participants explore the properties of hermitian operators and their significance.

Discussion Character

  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant notes the importance of hermitian operators in quantum mechanics and expresses uncertainty about the eigenvalues of the operator C, given that it returns the complex conjugate of the state function.
  • Another participant suggests writing down the complete definition of a hermitian operator to check if C satisfies the necessary properties.
  • A later reply indicates that C is not linear, which may impact its classification as hermitian.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether the operator is hermitian, and multiple viewpoints regarding its properties and implications are presented.

Contextual Notes

The discussion highlights the complexity of determining the hermitian nature of the operator, particularly in relation to its linearity and the definition of eigenvalues.

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-hey everyone,

this one might be a little too math based for this forum, but I ran across it studying for one of my quantum exams and it seemed like an interesting problem. Haven't figured it out completely.
We all know hermitian operators play a central role in quantum and so being able to tell if an operator is hermitian or not is important. Is the following operator hermitian?

C|Phi> = |Phi>*

(Takes a state function and gives the complex conjugate)

All the methods to show that an operator is hermitian (that I've seen) rely on the eigen-value equation

A|Phi> = a|Phi>

But the way this operator is defined, I'm not sure what the eigen values are (Or if it is an eigen value problem since the original function is not returned just its conjugate).

All I got was that for a Phi that is real, the only eigen value is one and it has infinite degeneracy. Not as exciting as faster than light travel, but dig in if you'd like...
 
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Have you tried writing down the complete definition of a hermitian operator and try to prove that C satisfies each of the properties.
 
Last edited:
Below is another hint. (don't peek until you've tried the above!)















C is not linear.
 
Thanks

Thanks Hurkyl,

Appreciate the push in the right direction.

Gabriel
 

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