7 May seminars at SISSA - new schedule

[Emanuele Tuillier Illingworth]

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MATHEMATICAL PHYSICS SEMINARS
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This is the new schedule for the seminars on thursday 7 may:


Prof. Kurusch E. Fard
(LMIA, Université de Haute Alsace, Mulhouse France)

at 14.00 in SISSA lecture room D


title: The pre-Lie relation, rooted trees and the Magnus expansion

abstract: W. Magnus' classical paper on the exponential solution of
differential equations for a linear operator received much attention
since its appearance in 1954, both in applied mathematics as well as
physics. In this talk we review recent work on the classical Magnus
expansion, unveiling a new structure by using the language pre-Lie
algebras as well as Hopf algebras of rooted trees. The pre-Lie relation
implies a reduction in the number of terms in the Magnus expansion. This
observation has to be seen in the light of the computation of
commutators in particular numerical integration schemes, which is a
major expense of many algorithms. Hence it appears to make sense to look
for ways to reduce the number of commutators. Motivations as well as
applications, ranging from numerical methods to the process of
renormalisation in perturbative quantum field theory, naturally appear.





prof. Jeffrey Rauch

(University of Michigan)

"Geometric optics II"

at 15.00 in lecture room D


-- 
Dr. Emanuele Tuillier Illingworth
Secretary of Mathematical Physics and Elementary Particle sectors
(+39) 040 37 87 598
SISSA
Via Beirut 2-4
Trieste, ITALY
tuillier at sissa.it