Navier–Stokes equations and nonlinear heat equations in modulation spaces with negative derivative indices

The Cauchy problems for Navier–Stokes equations and nonlinear heat equations are studied in modulation spaces . Though the case of the derivative index s=0 has been treated in our previous work, the case s≠0 is also treated in this paper. Our aim is to reveal the conditions of s, q and σ of for the existence of local and global solutions for initial data .