  Quantum condensation is used here as the basis for a phenomenological theory
of superfluidity and superconductivity. It leads to remarkably good
calculations of the transition temperatures T c of superfluid 3 He and 4 He, as
well as a large number of cuprate, heavy fermion, organic, dichalcogenide, and
bismuth oxide super- conductors. Although this approach may apply least to the
long coherence length metallics, reasonably good estimates are made for them,
and chevral superconductors. T c for atomic H is estimated. T c can be
calculated as a function of number density or density of states, and effective
mass of normal carriers; or alternatively with the Fermi energy as the only
input parameter. Predictions are made for a total of 26 superconductors and 4
superfluids. An estimate is also made for coherence lengths.

Superconductivity