Abstract
In this article, we study the long time decay of global solution to 3D incompressible Navier-Stokes equations. We prove that if u is an element of C([0, infinity), H-a,sigma(1) (R-3)) is a global solution, where H-a,sigma(1)(R-3) is the Sobolev-Gevrey spaces with parameters a > 0 and sigma > 1, then parallel to u(t)parallel to H-a,sigma(1)(R-3) decays to zero as time approaches infinity. Our technique is based on Fourier analysis.