Does the Phase Factor in Wave Function Matter?

Click For Summary

Discussion Overview

The discussion revolves around the significance of phase factors in wave functions, particularly in the context of quantum mechanics. Participants explore whether different representations of wave functions, specifically those differing by a phase factor, yield the same physical predictions, especially regarding probability amplitudes and boundary conditions.

Discussion Character

  • Technical explanation
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant questions whether a phase factor in the wave function affects the overall outcome, noting that their calculations yield different forms of the sine function.
  • Another participant asserts that if n is an integer, the two sine functions are equivalent, up to a sign, based on trigonometric identities.
  • A further response emphasizes the importance of boundary conditions and suggests that both forms may be valid for probability amplitudes under certain conditions.
  • It is noted that multiplying a wave function by an exponential phase factor results in an equivalent wave function, with a specific example provided where the phase factor is nπ.

Areas of Agreement / Disagreement

Participants express differing views on the implications of phase factors in wave functions. While some agree that the two forms of the sine function are equivalent under certain conditions, the broader question of their significance in quantum mechanics remains contested.

Contextual Notes

The discussion does not resolve whether the phase factor has implications beyond mathematical equivalence, leaving open questions about its physical significance in different contexts.

captain
Messages
163
Reaction score
0
does a phase factor (that can be represented by an imaginary exponential) in psi (the wave function) really matter? I am doing a problem and getting an answer that looks like sin[n(pi)x/a] when the answer is actually sin[n(pi)x/a-n(pi)]. I am just wondering at all if it makes any defference in the scheme of things. are both answers correct (because i know the probability will still be the same)?
 
Physics news on Phys.org
If n is an integer, then trigonometry shows that the two sins are the same..
 
pam said:
If n is an integer, then trigonometry shows that the two sins are the same..

up to a sign, as far as I remember trigonometry.
 
akhmeteli said:
up to a sign, as far as I remember trigonometry.

i understand that but are they both the same answer for a probability amplitude that fits the boundary conditions and where n in the form above is an integer?
 
captain said:
i understand that but are they both the same answer for a probability amplitude that fits the boundary conditions and where n in the form above is an integer?
You see, now you are supplying more details. Now your question sounds less philosophical and more mathematical. Why don't you just formulate the problem in its entirety, and then we might opine whether both answers are equally satisfactory.
 
captain said:
i understand that but are they both the same answer for a probability amplitude that fits the boundary conditions and where n in the form above is an integer?
If \psi is a wave function, then e^{i\phi}\psi is an equivalent wave function. In you case \phi=n\pi. -sin kx is equivalent to +sin kx.
 

Similar threads

  • · Replies 14 ·
Replies
14
Views
4K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 32 ·
2
Replies
32
Views
2K
  • · Replies 1 ·
Replies
1
Views
730
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K