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DTSTAMP:20260406T074312Z
UID:62728e6c0e01b796826206@ist.ac.at
DTSTART:20220509T153000
DTEND:20220509T163000
DESCRIPTION:Speaker: Raphaël Krikorian\nhosted by Kaloshin Group\nAbstract
 : To any symplectic real analytic diffeomorphisms of the 2-dimensional dis
 k (or annulus) admitting the origin as a non resonant fixed point one can 
 associate a formal series\, the Birkhoff Normal Form (BNF)\, which is inva
 riant by (formal) conjugations. One can prove that in general this formal 
 series is divergent. I shall address in this talk the following questions:
  does the convergence of the BNF imply integrability of the diffeomorphism
  in a neighborhood of the origin? Can such a diffeomorphism be perturbed i
 n the real analytic topology so that its BNF is convergent? Can such a dif
 feomorphism be perturbed so that it becomes integrable in a neighborhood o
 f the origin?
LOCATION:Mondi Seminar Room 2\, Central Building\, ISTA
ORGANIZER:jdeanton@ist.ac.at
SUMMARY:Raphaël Krikorian: Birkhoff Normal Forms\, frequency maps and loca
 l integrability
URL:https://talks-calendar.ista.ac.at/events/3756
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