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-->Dl<(nu)over bar> and B-->D*l<(nu)over bar>. Measurements of the lepton and D* polarizations can be used to search for and identify nonstandard 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 nonsupersymmetric 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.