Wave function phase relationships

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Discussion Overview

The discussion revolves around the properties and interpretations of wave functions in quantum mechanics, particularly focusing on the phase relationships of wave functions during transitions and their implications for probability distributions. Participants explore theoretical aspects, mathematical foundations, and conceptual interpretations related to wave functions and their behavior in various scenarios.

Discussion Character

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

Main Points Raised

  • One participant questions whether the relationship between a wave function and its conjugate, specifically that the probability is given by psi times its conjugate, holds universally or is limited to specific cases like bound and free particles.
  • Another participant clarifies that the relationship between a complex number and its conjugate is a universal property, asserting that the magnitude squared is always equal to the product of the number and its conjugate.
  • A different perspective is introduced regarding two spacelike separated electrons transitioning into spherical waves, proposing two possible outcomes: entanglement or overlapping without interaction.
  • One participant reiterates the relationship of the wave function and its conjugate, emphasizing the conditions under which a probabilistic interpretation is valid, and discusses the implications of external interventions on orbital state transitions.
  • Another participant speculates on the possibility of a point mass having separate locations for its momentum and gravitational moments, questioning the nature of solutions to the Schrödinger equation during transitions.
  • A later reply introduces the Noether theorem and its implications for energy conservation in phase space, raising questions about energy conservation during photon absorption or emission.

Areas of Agreement / Disagreement

Participants express differing views on the implications of wave function phase relationships and the nature of transitions in quantum systems. There is no consensus on the interpretations or outcomes of these discussions, indicating multiple competing views remain.

Contextual Notes

Some discussions hinge on assumptions about the nature of wave functions, the applicability of the Schrödinger equation, and the conditions under which probabilistic interpretations are valid. The complexities of orbital state transitions and energy conservation during photon interactions are also noted as areas of uncertainty.

DmplnJeff
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The wave function is complex. I was taught that its square (probability) was actually psi times it's conjugate. Does this relationship always hold or was this only for bound and free particles?

In other words is it possible for psi and psi* to change phases during orbital state transitions?
 
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That's a universal property of complex numbers--the magnitude squared of the number is always equal to the number times its conjugate. You can see this by looking at the definition of a complex number:

Z = x + iy
Z^* = x - iy
ZZ^* = (x + iy)(x - iy) = x^2 -i^2y^2 = x^2 + y^2

So in polar coordinates, where r = \sqrt{x^2 + y^2}, the number times its conjugate will always be r^2.
 
Let us suppose that there are two, spacelike separated electron in coordinate eigenstates. In the next moment, they begin to propagate as two spherical waves. (Better to say: the probability densities do propagate.)

What happens when these waves overlap? There are two possibilities (as I think):

1) The electrons entangle and there will be only one two-electron instead of two electrons,
2) They overlap without any interaction.
 
DmplnJeff said:
The wave function is complex. I was taught that its square (probability) was actually psi times it's conjugate. Does this relationship always hold or was this only for bound and free particles?

Its square modulus is always psi*psi. The easiness with which we ascribe a probabilistic interpretation to this modulus is dictated on whether psi is an element of a Hilbert space, thus is finite norm, or its modulus is finite, so it can be rescaled to unity.

DmplnJeff said:
In other words is it possible for psi and psi* to change phases during orbital state transitions?

The orbital state transitions are determined by an external intervention in an initially closed atomic system. The dynamics is then described by the Schroedinger equation whose solution cannot be really found analytically. The phase of the wavefunction during transition cannot be therefore determined exactly, but only proved to different than the one pertaining to a wavefunction of an unperturbed atomic system.
 
If psi^2 represents the probability distribution of the location, could psi and psi* represent two locations for the same object. For example a point mass could conceivably have a slightly separate location for its momentum moment and its gravitational moment.

Basically I'm trying to understand what solutions are available for Schroedinger's equation during the transition (if Schroedinger's equation applies?). So far what I've read amounts to a transition being some sort of miracle. It just happens.

Possible solutions depend on whether psi^2 is one number squared or two numbers.
 
Let me try rephrasing the question. It's my understanding the Hermitian nature of the phase space arises from the conservation of energy through the Noether theorem.

That theorem applies to non-dissipative spaces. Yet during the absorption (or emission) of a photon energy is not being conserved (locally). Why doesn't that make a difference?
 

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