# Tagged Questions

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### Non-degeneracy of ground state in quantum mechanics

In non-relativistic quantum mechanics, what are the necessary conditions on the potential (or on the hamiltonian in general) for the ground state to be non-degenrate?

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### Noether's Theorem in Quantum Mechanics

In classical mechanics:
If a Lagrangian L is preserved by an infinitesimal change in the state space variables qi -> qi + εKi(q) leads to only second order change in the Lagrangian:
$$ 0 = ...