How do Cooper pairs behave quantum mechanically compared to individual electrons below $T_c$?

Answer

Cooper pairs behave collectively as bosons, while individual electrons are fermions.

Individual electrons are fermions subject to the Pauli Exclusion Principle. Cooper pairs behave collectively as bosons, which allows a macroscopic fraction of them to condense into the single, shared lowest-energy quantum state.

How do Cooper pairs behave quantum mechanically compared to individual electrons below $T_c$?
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