A Schrodinger equation/Madelung equation phase transformation

Click For Summary
The discussion centers on the validity of the phase transformation of the wave function in quantum mechanics, specifically the equation ψ(x, t) = R(x, t) exp(iS(x, t)/ħ). It emphasizes that for the transformation to hold, both the amplitude R and phase S must maintain the same asymptotic behavior as the original wave function at infinity and at specific points. The conversation also touches on the implications of assuming R(x, t) ≥ 0, questioning whether this restriction limits the wave function's descriptive power. Additionally, the participants explore the polar decomposition of fields in the context of the Proca action, debating the independence of complex fields and their representations. Overall, the thread highlights the complexities of phase transformations and their mathematical foundations in quantum field theory.
  • #31
binbagsss said:
to which I said I understand it may seem illogical as you would then be introducing two more real quantities.
You did mention in post #8 that it would introduce more fields. However, once again, a number of other posts you have made in this thread made me wonder exactly what you understood.
 
Physics news on Phys.org
  • #32
PeterDonis said:
No, I said the opposite, that the amplitudes must be the same. Go read that post again.
i said, with that, as in with theta being the same, the amps must be the same. whereas i asked about differing theta. so basically if i did a polar decomposition using different amplitudes and phases for both B and B*, then I would end up with two more equations when varying the action. Ignoring the fact that that I would now have four independent variables, if I were to write ##B=B_1 e^{i\phi} ## and ##B*=B_2 e^{i\phi_2}## , then, from them being complex conjugates of each other, I would obtain constraints, such as ##B_1 \exp^{-i\theta}=B_2 \exp^{i\phi_2} ##, and ##B_1 \exp^{i\theta}=B_2 \exp^{-i\phi_2} ##but because of the differing amplitudes/arguments, neither the amplitudes or arguments in the exponents need to be the same?
 
  • #33
binbagsss said:
Ignoring the fact that that I would now have four independent variables
In other words, ignoring the fact that in the case you were asking about, the Proca equation, you don't. You only have two. Or more precisely, two for each 4-vector component (since the Proca equation is for a spin-1 vector field instead of a spin-0 scalar field); but all that means is that you stick a 4-vector index ##\mu## on ##B##.

You need to make up your mind what you are asking about. Are you asking about the actual Proca equation? Or are you asking about some other case, which AFAIK has no physical relevance and is not discussed in the literature, where you somehow have four independent variables instead of two? You said before that you were asking about the Proca equation. Are you now changing the discussion to be about something else?
 
  • Like
Likes renormalize

Similar threads

  • · Replies 5 ·
Replies
5
Views
2K
Replies
1
Views
1K
Replies
12
Views
5K
Replies
9
Views
1K
  • · Replies 0 ·
Replies
0
Views
1K
Replies
6
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 10 ·
Replies
10
Views
3K