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SUMMARY:Surface subgroups of graphs of free groups - Henry Wilton (Univers
 ity of Cambridge)
DTSTART:20170621T103000Z
DTEND:20170621T113000Z
UID:TALK73016@talks.cam.ac.uk
CONTACT:INI IT
DESCRIPTION:A well known question\, usually attributed to Gromov\, asks wh
 ether every hyperbolic group is either virtually free or contains a surfac
 e subgroup. I&rsquo\;ll discuss the answer to this problem for the class o
 f groups in the title when the edge groups are cyclic. &nbsp\;The main the
 orem is a result about free groups F which is of interest in its own right
 : whether of not an element w of F is primitive can be detected in the abe
 lianizations of finite-index subgroup of F. &nbsp\;I&rsquo\;ll also mentio
 n an application to the profinite rigidity of the free group.
LOCATION:Seminar Room 1\, Newton Institute
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