The scaling theory of critical phenomena has been successfully extended for
classical first order transitions even though the correlation length does not
diverge in these transitions. In this paper we apply the scaling ideas to
quantum first order transitions. The usefulness of this approach is illustrated
treating the problems of a superconductor coupled to a gauge field and of a
biquadratic Heisenberg chain, at zero temperature. In both cases there is a
latent energy associated with their discontinuous quantum transitions. We
discuss the effects of disorder and give a general criterion for it's relevance
in these transitions.Comment: 6 pages, 2 figures, misprints corrected and a reference added.
Version published in PHYSICA