Seminars at the Faculty of Informatics

Exponential variational integrators

The Faculty of Informatics is pleased to announce a seminar given by Odysseas Kosmas

DATE: Wednesday, April 1st 2015
PLACE: USI Lugano Campus, room A34, Red building (Via G. Buffi 13)
TIME: 10.30

ABSTRACT:
We concentrate on physical problems where the kinetic and potential energy of their Lagrangian depend only on the generalized velocity and generalized position, respectively. Such systems are treated within the discrete variational integrators formalism.
Towards this purpose we derive higher order exponential variational integration methods for the required numerical integrations. More specifically, for the derivation of such integrators, the action integral along the curve segment is defined by using a discrete Lagrangian that depends only on the end points of the interval. Then high order integrators are obtained by defining the discrete Lagrangian in any time-segment (on regular or non regular time grid) as a weighted sum of the Lagrangian at intermediate points.
We also discuss PDEs that appear in various physical problems and can be written as multisymplectic systems, in which each independent variable has a distinct symplectic structure. For the derivation of the latter integrators, the necessary discrete Lagrangian is now expressed at the appropriate discrete jet bundle using triangle and square discretization.

BIO:
" 2002: Dipl.-Math., Department of Mathematics, University of Ioannina
" 2006 - 2009: Dr., PhD in Computer Science, University of Peloponnese
" 2009 - 2011: Associate researcher of the Mathematical Modeling and Complex Systems laboratory, University of Peloponnese
" 2011 -: Postdoc researcher, Chair of Applied Dynamics, University of Erlangen-Nuremberg

HOST: Prof. Rolf Krause