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DTSTART:20250330T030000
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DTSTAMP:20260424T143428Z
UID:66a376b9cc377973707124@ist.ac.at
DTSTART:20250204T140000
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DESCRIPTION:Speaker: Gil Bor\nhosted by Kaloshin Group\nAbstract: This talk
  is concerned with a billiard version of Jacobis Last Geometric Statement 
 and its generalizations. Given a point O inside an oval billiard table (or
  mirror)\, one considers the family of rays emanating from O and the caust
 ic (or envelope) of the reflected family of rays after n reflections off t
 he walls of the table. I will describe two related statements:(1) Theorem:
  for a generic O this caustic has at least 4 cusps for each positive integ
 er n. (2)  Conjecture: for an elliptic table there are exactly four (ordin
 ary) cusps. I will describe a proof of (1) and  partial results concerning
   (2). This is joint work with Mark Spivakovsky (Toulouse) and Serge Tabac
 hnikov (Penn State). References:* https://arxiv.org/abs/2112.07852* https:
 //arxiv.org/abs/2406.11074.
LOCATION:Office Bldg West / Ground floor / Heinzel Seminar Room (I21.EG.101
 )\, ISTA
ORGANIZER:cfrancois@ist.ac.at
SUMMARY:Gil Bor: Four cusps of caustics by reflection
URL:https://talks-calendar.ista.ac.at/events/5136
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