Complex sentence: By the Pauli principle, no quantum state can be occupied by more than one fermion (with identical properties); thus a Fermi gas, unlike a Bose gas, is prohibited from condensing into a Bose-Einstein condensate.
Split into simpler sentences: By the Pauli principle, no quantum state can be occupied by more than one fermion with identical properties. Thus a Fermi gas, unlike a Bose gas, is prohibited from condensing into a Bose-Einstein condensate.