Configurations for Non-Interacting Particles with Total Energy of 2E

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Homework Statement


List all possible configurations for distinguishable particles, identical bosons and identical fermions where the system has a total energy of 2E and contains two non-interacting particles. The energy-level structure is 0, 1ER, 1EL and 2E (where 1ER and 1EL are degenerate).


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The Attempt at a Solution


I know the situation for distinguishable particles.
I think I know that bosons can be in the same quantum state, so that includes the possibility of the two particles both being in 1ER and then in 1ER (I make it four configurations in total).
What I don't know is whether the Pauli exclusion principle makes it impossible for the two fermions to be at the same energy level, if there are two degenerate levels with the same energy. Is it possible for them to be at a) 2E and 0, and b) 1ER and 1EL...or does the exclusion principle cancel that possibility?
Thanks
 
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The Pauli exclusion principle says that two fermions can't be in the same state at the same time. Since 1ER and 1EL are different states, the Pauli exclusion principle doesn't apply.
 
Thanks
So two fermions in the same system can have the same energy...providing they have a different quantum state?
 
Yup, like two electrons in the n=1 state of the hydrogen atom.
 
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