Can exited states exist without a ground state?

  • Context: Graduate 
  • Thread starter Thread starter Mark_M
  • Start date Start date
  • Tags Tags
    Ground States
Click For Summary

Discussion Overview

The discussion revolves around the existence of excited states in quantum systems, particularly in the context of the Klein-Gordon and Dirac equations, when a ground state is posited to not exist under certain conditions. The inquiry explores theoretical implications and the nature of energy states in quantum mechanics.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant questions whether excited states can exist if the ground state is asserted to not exist, suggesting that the first excited state might then assume the role of the ground state.
  • Another participant asserts that the ground state, defined as the state of lowest energy, must exist, challenging the premise of the initial question.
  • A further response clarifies that under specific conditions related to vector and scalar potentials, the Klein-Gordon or Dirac equations may lack a corresponding wave function for the ground state, raising the question of whether excited states would also be absent under those conditions.
  • It is argued that if a system has no solutions, it cannot be considered a valid model, and that any existing solutions would imply the presence of a ground state as the lowest energy solution.

Areas of Agreement / Disagreement

Participants exhibit disagreement regarding the existence of a ground state and its implications for excited states, with no consensus reached on the validity of the initial premise.

Contextual Notes

The discussion highlights limitations related to the assumptions of the model, particularly concerning the conditions under which the Klein-Gordon and Dirac equations are analyzed, and the implications of having no solutions.

Mark_M
Messages
3
Reaction score
0
Hello everybody,

I have a question which might be silly. Nevertheless: Can exited states exist if you know that the ground state do not exist? Will in such a case first exited state become the ground state?

Thanks.
 
Physics news on Phys.org
The ground state is the state of lowest energy. How could it not exist?
 
When I say it does not exists I mean, that under some conditions on vector and scalar potentials, the Klein Gordon or Dirac equation will not have a wave function which corresponds to the ground state. Therefore can we conclude from there that under the same conditions the exited states will not exist?
 
Mark_M said:
When I say it does not exists I mean, that under some conditions on vector and scalar potentials, the Klein Gordon or Dirac equation will not have a wave function which corresponds to the ground state. Therefore can we conclude from there that under the same conditions the exited states will not exist?

If your system has no solutions at all than it is not a valid model and if it has solutions, than the one(s) with lowest energy will be the ground state. I don't how one could possibly have a system with a ground state that doesn't exist. I can't make sense of your question.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 16 ·
Replies
16
Views
4K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 8 ·
Replies
8
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
12
Views
2K