Table of Contents
Fetching ...

A note on stochastic semilinear dissipative evolution equations

Carlo Marinelli

TL;DR

This note addresses the well-posedness of stochastic semilinear dissipative evolution equations with additive noise, where the linear part $A$ generates a compact contraction semigroup and the nonlinearity $f$ is a monotone superposition operator. Existence and uniqueness of a probabilistically strong mild solution are established by approximating $f$ with Yosida regularizations, obtaining pathwise a priori estimates, and leveraging a novel compactness result for deterministic convolutions to pass to the limit. The approach avoids variational structure on $A$ and Aubin–Lions–Simon-type compactness, extending well-posedness to broader operator classes. The resulting solution $u$ decomposes into a deterministic part plus the stochastic convolution, with the remainder $v=u-S\diamond(B\cdot W)$ enjoying strong continuity in $L^1$ and weak continuity in $L^2$, and the framework accommodates quasi-monotone extensions of $A$ and $f$.

Abstract

Existence and uniqueness of mild solutions to a class of semilinear stochastic evolution equations with additive noise is proved. The linear part of the drift term is the generator of a compact semigroup of contractions, while the nonlinear part is only assumed to be the superposition operator associated to a decreasing function.

A note on stochastic semilinear dissipative evolution equations

TL;DR

This note addresses the well-posedness of stochastic semilinear dissipative evolution equations with additive noise, where the linear part generates a compact contraction semigroup and the nonlinearity is a monotone superposition operator. Existence and uniqueness of a probabilistically strong mild solution are established by approximating with Yosida regularizations, obtaining pathwise a priori estimates, and leveraging a novel compactness result for deterministic convolutions to pass to the limit. The approach avoids variational structure on and Aubin–Lions–Simon-type compactness, extending well-posedness to broader operator classes. The resulting solution decomposes into a deterministic part plus the stochastic convolution, with the remainder enjoying strong continuity in and weak continuity in , and the framework accommodates quasi-monotone extensions of and .

Abstract

Existence and uniqueness of mild solutions to a class of semilinear stochastic evolution equations with additive noise is proved. The linear part of the drift term is the generator of a compact semigroup of contractions, while the nonlinear part is only assumed to be the superposition operator associated to a decreasing function.

Paper Structure

This paper contains 10 sections, 15 theorems, 70 equations.

Key Result

Lemma 2.1

Let $S$ be a contraction semigroup on a Hilbert space $H$, $v_0 \in H$, $f \in L^1_\textnormal{loc}(\mathbb{R}_+;H)$, and $v = S v_0 + S \ast f$. Then

Theorems & Definitions (35)

  • Lemma 2.1
  • proof
  • Proposition 2.2
  • proof
  • Lemma 2.3
  • proof
  • Lemma 2.4
  • proof
  • Corollary 2.5
  • proof
  • ...and 25 more