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Drift-preserving numerical integrators for stochastic Hamiltonian systems

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 نشر من قبل David Cohen
 تاريخ النشر 2019
  مجال البحث الهندسة المعلوماتية
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The paper deals with numerical discretizations of separable nonlinear Hamiltonian systems with additive noise. For such problems, the expected value of the total energy, along the exact solution, drifts linearly with time. We present and analyze a time integrator having the same property for all times. Furthermore, strong and weak convergence of the numerical scheme along with efficient multilevel Monte Carlo estimators are studied. Finally, extensive numerical experiments illustrate the performance of the proposed numerical scheme.

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