Strong dissipativity of generalized time-fractional derivatives and quasi-linear (stochastic) partial differential equations

In this paper strong dissipativity of generalized time-fractional derivatives on Gelfand triples of properly in time weighted L-p-path spaces is proved. In particular, as special cases the classical Caputo derivative and other fractional derivatives appearing in applications are included. As a consequence one obtains the existence and uniqueness of solutions to evolution equations on Gelfand triples with generalized time-fractional derivatives. These equations are of type d/dt (k * u)(t) + A(t, u(t)) = f(t), 0 < t < T, with (in general nonlinear) operators A(t, .) satisfying general weak monotonicity conditions. Here kis a non-increasing locally Lebesgue-integrable nonnegative function on [0, infinity) with lim(s ->infinity) k(s) = 0. Analogous results for the case, where f is replaced by a time-fractional additive noise, are obtained as well. Applications include generalized time-fractional quasi-linear (stochastic) partial differential equations. In particular, time-fractional (stochastic) porous medium and fast diffusion equations with ordinary or fractional Laplace operators and the time-fractional (stochastic) p-Laplace equation are covered. (C) 2021 Elsevier Inc. All rights reserved.