Global solutions to one-dimensional compressible Navier-Stokes-Poisson equations with density-dependent viscosity

In this paper, we prove the global existence of weak solutions to one-dimensional compressible isentropic Navier-Stokes-Poisson equations with density-dependent viscosity and free boundaries. The initial density rho(0)is an element of W-1,W-2n is bounded below by a positive constant, and the initial velocity u(0)is an element of L-2n. In contrast to Jiang ["Global weak solutions to 1D compressible isentropic Navier-Stokes equations with density-dependent viscosity," Methods Appl. Anal. 12, 239 (2005)], the Sobolev exponent n is less in this paper, and the viscosity coefficient mu=mu(rho) is a general function of rho including the cases mu(rho)=c(0)rho(theta) (0 <theta < 1) and mu(rho)=c(0), where c(0) is a positive constant.