Polarization Measurements and T-Violation in Exclusive Semileptonic B Decays

We provide a general analysis of time reversal invariance violation in the exclusive semileptonic B decays B to D l nu and B to D* l nu. Measurements of the lepton and D* polarizations can be used to search for and identify non-standard model sources of T violation. Upper limits are placed on the T-odd polarization observables in both the supersymmetric R-parity conserving and R-parity breaking theories, as well as in some non-supersymmetric extensions of the standard model, including multi-Higgs-doublet models, leptoquark models, and left-right symmetric models. It is noted that many of these models allow for large T-violating polarization effects which could be within the reach of the planned B factories.