Periodic L_p Estimates by R-Boundedness: Applications to the Navier-Stokes Equations

General evolution equations in Banach spaces are investigated. Based on an operator-valued version of de Leeuw's transference principle, time-periodic L(p )estimates of maximal regularity type are carried over from R-bounds of the family of solution operators (R-solvers)to the corresponding resolvent problems. With this method, existence of time-periodic solutions to the Navier-Stokes equations is shown for two configurations: in a periodically moving bounded domain and in an exterior domain, subject to prescribed time-periodic forcing and boundary data