Phases and properties of color superconductors

Cold and dense matter is expected to be in a color-superconducting state. Here we review two calculations, relevant for fundamental properties and applications of color superconductivity, respectively: the weak-coupling QCD calculation of the fermionic energy gap together with the magnetic screening masses of the gauge bosons, and the calculation of bulk viscosity from a non-leptonic electroweak process. These calculations are supplemented by a discussion of color superconductors with mismatched Fermi momenta, and they are embedded in the context of the state of the art by giving an overview of previous and ongoing work and future directions.