arXiv subjects

Marek Kryspin

Publications and source records attributed to Marek Kryspin.

4 recordsLinked to original sources

arXiv2024

Systems of parabolic equations with delays: Continuous dependence on parameters

Results on continuous dependence on parameters, as well as on regularization, of solutions to linear systems of parabolic partial differential equations of second order with delay are given. One of the main features is that the topology on the zero order and delay coefficients is the weak-* topology on an $L_{\infty}$ space, whereas the assumptions on the second- and first-order coefficients are slightly stronger. This is important in the context of generation of linear skew-product dynamical systems by such equations.

math.AP↗

arXiv2024

Oseledets Decomposition on Sub semiflows

The existence of the Oseledets decomposition on continuously embedded subspaces of Banach spaces is proved in this paper. Natural assumptions facilitating such transfer of the Oseledets decomposition are presented, notably conditions often met by dynamical systems generated by differential equations.

math.FA↗

arXiv2023

Two dynamical approaches to the notion of exponential separation for random systems of delay differential equations

This paper deals with the exponential separation of type II, an important concept for random systems of differential equations with delay, introduced in \JM\ et al.~\cite{MiNoOb1}. Two different approaches to its existence are presented. The state space $X$ will be a separable ordered Banach space with $\dim X\geq 2$, dual space $X^{*}$ and positive cone $X^+$ normal and reproducing. In both cases, appropriate cooperativity and irreducibility conditions are assumed to provide a family of generalized Floquet subspaces. If in addition $X^*$ is also separable, one obtains a exponential separation of type II. When this is not the case, but there is an Oseledets decomposition for the continuous semiflow, the same result holds. Detailed examples are given for all the situations, including also a case where the cone is not normal.

math.DS↗

arXiv2022

Parabolic Differential Equations with Bounded Delay

We show the continuous dependence of solutions of linear nonautonomous second order parabolic partial differential equations (PDEs) with bounded delay on coefficients and delay. The assumptions are very weak: only convergence in the weak-* topology of delay coefficients is required. The results are important in the applications of the theory of Lyapunov exponents to the investigation of PDEs with delay.

math.AP↗