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Dynamical systems method (DSM) for unbounded operators

A. G. Ramm
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Abstract

Let $L$ be an unbounded linear operator in a real Hilbert space $H$, a generator of $C_0$ semigroup, and $g:H\to H$ be a $C^2_{loc}$ nonlinear map. The DSM (dynamical systems method) for solving equ$ $F(v):=Lv+gv=0$ consists of solving the Cauchy problem $\dot {u}=Φ(t,u)$, $u(0)=u_0$, where $Φ$ is a suitable operator, and proving that i) $\exists u(t) \quad \forall t>0$, ii) $\exists u(\infty)$, and iii) $F(u(\infty))=0$.

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A. G. Ramm. 2004-04-23. Dynamical systems method (DSM) for unbounded operators. https://arxiv.org/abs/math/0404436

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