We discuss the use of massive vectors for the interpretation of some recent
experimental anomalies, with special attention to the muon g−2. We restrict
our discussion to the case where the massive vector is embedded into a
spontaneously broken gauge symmetry, so that the predictions are not affected
by the choice of an arbitrary energy cut-off. Extended gauge symmetries,
however, typically impose strong constraints on the mass of the new vector
boson and for the muon g−2 they basically rule out, barring the case of
abelian gauge extensions, the explanation of the discrepancy in terms of a
single vector extension of the standard model. We finally comment on the use of
massive vectors for B-meson decay and di-photon anomalies.Comment: 25 pages, 1 figure. References added, to appear in JHE