BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Moduli Spaces of Gorenstein Quasi-Homogenous Surface Singularities
  - Pratoussevitch\, A (Liverpool)
DTSTART:20110125T100000Z
DTEND:20110125T110000Z
UID:TALK29663@talks.cam.ac.uk
CONTACT:Mustapha Amrani
DESCRIPTION:Gorenstein quasi-homogeneous surface singularities\, studied b
 y Dolgachev\, Neumann and others\, correspond to lifts of Fuchsian groups 
 into the universal covering of PSL(2\,R). I will show that the space of Go
 renstein quasi-homogeneous surface singularities corresponding to a certai
 n Fuchsian group is a finite affine space of Z/mZ-valued functions on the 
 Fuchsian group\, called m-Arf functions. Using m-Arf functions\, I will co
 unt connected components of the space of Gorenstein quasi-homogeneous surf
 ace singularities and prove that any connected component is homeomorphic t
 o a quotient of R^d by a discrete group. This work is connected to the ear
 lier results of Atiyah and Mumford on spin structures on compact Riemann s
 urfaces and of Jarvis\, Kimura and Vaintrob on moduli spaces of higher spi
 n curves. This is joint work with Sergey Natanzon.\n
LOCATION:Seminar Room 1\, Newton Institute
END:VEVENT
END:VCALENDAR