motivation behind using Bochner spaces in study of time dependent parabolic problems

32 Views Asked by At

I am studying the theory of parabolic partial differential equation of type $u_t-\Delta u=f$. Now while defining the weak formulation we have used the Bochner spaces $L^2(0,T;H_0^1(\Omega))$. Can anyone explain why we consider these vector valued spaces to study parabolic equations. Can't we take functions of $(x,t)$ directly?