Talk abstract details

We present a study of shearfree perfect fluids obeying a barotropic equation of state, assuming that the spatial divergence of the magnetic part of the Weyl tensor is zero.

We discuss different subcases in which one can demonstrate that either the vorticity or the expansion vanishes (such as the case of a $\gamma$-law equation of state), we point out the remaining difficulties in the general case and we present a classification of the resulting solutions.