Wave function phase relationships

In summary: If energy is being conserved then the phase space shouldn't change.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? The magnitude squared of the number is always equal to the number times its conjugate. This is a universal property of complex numbers.
  • #1
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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  • #2
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:

[tex]Z = x + iy[/tex]
[tex]Z^* = x - iy[/tex]
[tex]ZZ^* = (x + iy)(x - iy) = x^2 -i^2y^2 = x^2 + y^2[/tex]

So in polar coordinates, where [tex]r = \sqrt{x^2 + y^2}[/tex], the number times its conjugate will always be [tex]r^2[/tex].
 
  • #3
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.
 
  • #4
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.
 
  • #5
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.
 
  • #6
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?
 

1. What is a wave function phase relationship?

A wave function phase relationship refers to the relationship between different parts of a wave function, which describes the behavior and properties of a quantum system. This relationship is determined by the phase, which is a measure of the position and direction of a wave at a given point in time.

2. How is the phase of a wave function measured?

The phase of a wave function can be measured using various methods, depending on the specific system being studied. In general, it involves measuring the amplitude and frequency of the wave at different points in space and time, and then using mathematical equations to determine the phase. This can be done using tools such as interferometers and phase shifters.

3. What are the different types of phase relationships in a wave function?

There are two main types of phase relationships in a wave function: in-phase and out-of-phase. In-phase refers to when the phases of two parts of the wave function are aligned and produce a larger amplitude, while out-of-phase refers to when the phases are opposite and cancel each other out, resulting in a smaller amplitude.

4. How do phase relationships affect the behavior of a quantum system?

The phase relationships in a wave function play a crucial role in determining the behavior of a quantum system. In-phase relationships can result in constructive interference, where the amplitude of the wave is increased, while out-of-phase relationships can lead to destructive interference, reducing the amplitude. This can have a significant impact on the properties and interactions of particles in the system.

5. Can the phase relationship of a wave function change?

Yes, the phase relationship of a wave function can change over time. This can occur due to external factors such as interactions with other particles or forces, or due to changes in the system itself. It is important for scientists to understand and control these changes in order to accurately predict and manipulate the behavior of quantum systems.

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