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arXiv · 1709.01018

On a randomized backward Euler method for nonlinear evolution equations with time-irregular coefficients

Monika Eisenmann·Mihály Kovács·Raphael Kruse·Stig Larsson
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Abstract

In this paper we introduce a randomized version of the backward Euler method, that is applicable to stiff ordinary differential equations and nonlinear evolution equations with time-irregular coefficients. In the finite-dimensional case, we consider Carath\'eodory type functions satisfying a one-sided Lipschitz condition. After investigating the well-posedness and the stability properties of the randomized scheme, we prove the convergence to the exact solution with a rate of $0.5$ in the root-mean-square norm assuming only that the coefficient function is square integrable with respect to the temporal parameter. These results are then extended to the numerical solution of infinite-dimensional evolution equations under monotonicity and Lipschitz conditions. Here we consider a combination of the randomized backward Euler scheme with a Galerkin finite element method. We obtain error estimates that correspond to the regularity of the exact solution. The practicability of the randomized scheme is also illustrated through several numerical experiments.

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Monika Eisenmann, Mihály Kovács, Raphael Kruse, Stig Larsson. 2017-09-04. On a randomized backward Euler method for nonlinear evolution equations with time-irregular coefficients. https://doi.org/10.1007/s10208-018-09412-w

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