Jg. Heywood et Od. Walsh, A COUNTEREXAMPLE CONCERNING THE PRESSURE IN THE NAVIER-STOKES EQUATIONS, AS T-]0+, Pacific journal of mathematics, 164(2), 1994, pp. 351-359
We show the existence of solutions of the Navier-Stokes equations for
which the Dirichlet norm, \\delu(t)\\L2(OMEGA), of the velocity is con
tinuous as t = 0, while the normalized L2-norm, \\p(t)\\L2(OMEGA)/R, o
f the pressure is not. This runs counter to the naive expectation that
the relative orders of the spatial derivatives of u, p and u(t) shoul
d be the same in a priori estimates for the solutions as in the equati
ons themselves.