Which algebra vectors satisfy this (Trying to derive Schrödinger)

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Discussion Overview

The discussion centers on the nature of the wave-function in quantum mechanics, specifically exploring why it is complex and examining the conditions under which a vector basis can yield complex solutions. The scope includes theoretical aspects related to the Schrödinger equation and vector algebra.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant proposes that an orthonormal basis of vectors/functions labeled f_{E,k} can be examined to derive complex solutions, suggesting that the only orthonormal solution may be f_{E,k}(x,t)=\exp(i(kx-Et)).
  • Another participant notes that the factors k^2 and E should be replaced by operators, indicating a need for axioms that lead to complex algebra as the only solution.
  • A question is raised about the nature of V(x,t), with a suggestion that it is not merely a placeholder but has specific implications in the context of the discussion.
  • Clarification is provided that V(x,t) is intended to be an arbitrary real-valued function, while k^2 and E are described as real linear operators.
  • One participant expresses confusion regarding the clarity of the original post and questions the language used.
  • Another participant challenges the correctness of the formulation, pointing out that the discussion seems to conflate aspects of the time-independent Schrödinger equation with a time-dependent potential.

Areas of Agreement / Disagreement

Participants express differing levels of understanding and clarity regarding the original post, with some questioning the formulation and others seeking to refine the mathematical expressions. There is no consensus on the conditions necessary to derive complex solutions or on the interpretation of the variables involved.

Contextual Notes

Limitations include potential misunderstandings of the mathematical formulation, unclear definitions of terms, and the need for more precise mathematical context regarding the operators and functions discussed.

Gerenuk
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Hi,

I was wondering why the wave-function in quantum mechanics is complex. There are a lot of threads in the physics section and I've downloaded a lot of papers, but they seem quite technical. So I'd like to examine the following idea (sorry if I use sloppy terms ;) ):

I have an orthonormal basis of vectors/functions which can be labeled with two indices f_{E,k} and which are "two-dimensional". It's not just a column vector, but rather f_{E,k}(x,t). The vector algebra is undetermined (could be any linear algebra).

Now I have two conditions
k^2f_{E,k}+V(x,t)f_{E,k}=Ef_{E,k}
\forall a: f_{E,k}(x+Ea,t+ka)=f_{E,k}(x,t)
(btw, the second is in a way equivalent to E=mc^2)

Is it now possible to proof that the only orthonormal solution for this is a complex algebra with
f_{E,k}(x,t)=\exp(i(kx-Et))?

Please add definitions (for scalar product and so on) as appropriate!
Or which other definitions/conditions do I need to get that complex solution uniquely?
 
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I notice he above factors k^2 and E have to be replaced by operators.

Anyway, the task is to find some axioms similar to the above, which yield the complex algebra as the only solution.
 
What is V(x,t)? Because I have a feeling you mean something specific, not just a placeholder for an arbitrary function.
 
Basically the above problem comes from the Schrödinger equation. Sometimes I might be missing concepts, but maybe you can add them.

The function V(x,t) is supposed to be an arbitrary real-valued function. k^2 and E are a real linear operators. So now I'm wondering which other conditions I need to add to make the vector basis of the algebraic solution isomorphic to the above complex solution.

Please formulate this more mathematically correctly whoever can. The aim is to show the vector basis must be complex numbers.
 
what are you talking about? this barely makes sense. is english your first language?
 
Ice, If you have trouble with both language and maths, please devote your time to complaining in other forums.
 
It might just be me, but you have specified anything about your "K2" being a second derivative with respect to position. Also, what you are sort of writing is the time independent Schrödinger equation so having a time dependent potential function V is not correct.
 

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