How Does Degeneracy Affect Energy Levels and Quantum Numbers in a 3D Box?

AI Thread Summary
The discussion focuses on calculating the lowest energy levels and quantum numbers for a spin-less particle in a 3D box with dimensions (2a, a, a). The main query is whether the magnetic quantum number (ml) contributes to degeneracy when there is no external magnetic field, and if it should be counted alongside the principal (n) and azimuthal (l) quantum numbers. Participants clarify that the concept of quantum numbers should not be confused with energy levels, emphasizing that the ground state must adhere to the Pauli exclusion principle. Additionally, the discussion touches on how to determine the total energy of three identical non-interacting spin-less particles in this box, noting that identical quantum numbers cannot occupy the same state. The conversation highlights the importance of understanding the relationship between quantum numbers and energy states in quantum mechanics.
indie452
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okay this isn't exactly me asking how to solve a question but just to verify the theory in my head.

i need to calculate the 4 lowest energy levels for a 3d box (that has sides (2a,a,a)) and show all the quantum numbers (i imagine it means the x,y,z components of n, l, ml) and give the degeneracy values. also note the particles are spin-less.

this i can do but what i don't know is, considering there is no external magnetic field does the values of ml degenerate into a single energy value?
Basically do i count ml as a quantum number that affects degeneracy?

cause so far i have counted the variations of the n components and l components.
i.e if i have n(1,1,2) then the l values are(0,0,0 or 1) which results in 2 possibilities so degeneracy = 2.
so do i count the ml?

also the next question asks about if 3 identical non-interacting spin-less particles are confined in this box find the lowest total energy for these particles.
how would this work? i thought pauli exclusion principle prevented particles with identical quantum numbers being in the same state? and if all the qm numbers are the same it would have to be in the same state right?

thanks for any help
 
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You are talking about a 3D rectangular box, so why you are using the quantum number of a Hydrogen atom? Quantum number is just a representing number of the system state and they are associated with different wavefunction for different system.

Ground state means the 'allowed' state with the minimum energy. Here, the 'allowed state' means state satisfying the Pauli exclusion principle. Also, please do not mix the concept of quantum number and the energy.
 
what do you mean I'm using the hydrogen quantum number that i shouldn't be?
 
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