How to understand the physics meanings for system x--> ix?

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Discussion Overview

The discussion centers on the transformation of variables in the context of the harmonic oscillator, specifically the implications of substituting \( x \) with \( ix \) and the resulting effects on energy and wave functions. Participants explore both the mathematical and physical interpretations of these transformations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants note that substituting \( x \) with \( ix \) leads to energy values \( E_n = -(n + 1/2) \) and changes the wave function accordingly.
  • Others argue that the transformation \( p \to ip \) must also be applied for the results to hold true.
  • One participant questions the necessity of the transformation \( p \to ip \) and suggests it may be a mathematical quirk without deeper significance.
  • There is a query regarding how to calculate energy when substituting \( x \) with \( -x \) and whether the Hamiltonian's dependence on \( p \) is relevant in this context.

Areas of Agreement / Disagreement

Participants express differing views on the necessity and implications of the transformations, particularly regarding the relationship between \( x \) and \( p \). The discussion remains unresolved, with multiple competing perspectives on the physical meanings and mathematical validity of the transformations.

Contextual Notes

Some limitations include the potential dependence on specific definitions and the unresolved nature of the mathematical steps involved in the transformations.

dongsh2
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For example, in Harmonic oscillator, we find E--> -E when x--> i x. How to understand physical meanings or in mathematics? How to understand the wave function in this case?
 
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dongsh2 said:
For example, in Harmonic oscillator, we find E--> -E when x--> i x.
I don't think it is true, unless one also makes the transformation p->ip.
 
In harmonic oscillator, if we take x--> ix, the energy becones E_n= -(n+1/2), the wave function is changed by replacing "ix". We can check the cases n=0,1, etc. we find they indeed satisfy the Schrödinger equation.

What is the reason why also p-->ip?
 
A
dongsh2 said:
In harmonic oscillator, if we take x--> ix, the energy becones E_n= -(n+1/2), the wave function is changed by replacing "ix". We can check the cases n=0,1, etc. we find they indeed satisfy the Schrödinger equation.What is the reason why also p-->ip?

A mathematical quirk maybe - every mathematical idiosyncrasy doesn't necessarily have some deep meaning.

Thanks
Bill
 
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dongsh2 said:
In harmonic oscillator, if we take x--> ix, the energy becones E_n= -(n+1/2), the wave function is changed by replacing "ix". We can check the cases n=0,1, etc. we find they indeed satisfy the Schrödinger equation.

What is the reason why also p-->ip?
How do you calculate energy when you take x->-x? Do you perhaps take the Hamiltonian to act on the wave function? If yes, does that Hamiltonian depend also on p?
 

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