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SUMMARY:Stephen McKean (Harvard U.)
DTSTART:20230113T140000Z
DTEND:20230113T150000Z
DTSTAMP:20260423T021101Z
UID:LAGARTOS/52
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/LAGARTOS/52/
 ">Circles of Apollonius two ways</a>\nby Stephen McKean (Harvard U.) as pa
 rt of (LAGARTOS) Latin American Real and Tropical Geometry Seminar\n\n\nAb
 stract\nThere are eight circles tangent to a given trio of circles\, provi
 ded that one works over the complex numbers. Over the reals\, some of thes
 e tangent circles can go missing. In order to obtain an invariant count of
  tangent circles\, one needs to count each tangent circle with an appropri
 ate weight. I will talk about two geometric characterizations of such coun
 ting weights\, as well as how to use these counting weights over any field
  of characteristic not 2.\n
LOCATION:https://researchseminars.org/talk/LAGARTOS/52/
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