Conformally flat polytropes for anisotropic matter
  We analyze in detail conformally flat spherically symmetric fluid distributions, satisfying a polytropic equation of state. Among the two possible families of relativistic polytropes, only one contains models which satisfy all the required physical conditions. The ensuing configurations are necessarily anisotropic and show interesting physical properties. Prospective applications of the presented models to the study of super-Chandrasekhar white dwarfs, are discussed. 
L. Herrera, A. Di Prisco, W. Barreto, J. Ospino
gr-qc math-ph math.MP