University of Cambridge > Talks.cam > Differential Geometry and Topology Seminar > Cycles in moduli spaces of graphs

  Browse A-Z

Log in

University Account External (via Google)

🔐 Log In

Information on

Subscribing to talksdetails Finding a talkdetails Adding a talkdetails Disseminating talksdetails Help and Documentationdetails

ℹī¸ Information

Cycles in moduli spaces of graphs

Download to your calendar using vCal

  • UserKaren Vogtmann, Cornell
  • ClockWednesday 04 March 2015, 16:00-17:00
  • HouseMR13.

If you have a question about this talk, please contact Ivan Smith .

Moduli spaces of finite metric graphs paramaterize many phenomena in science and mathematics. In this talk I will discuss the topology of such spaces. If the graphs have no univalent vertices the rational cohomology of the moduli space is the cohomology of the group Out(F_n) of outer automorphisms of a free group. This cohomology vanishes in high and low dimensions, but Euler characteristic calculations show that there must be many classes in the middle range. I will summarize what we know and then show how tools from topology, representation theory and modular forms can be used to construct a large number of cocycles; the idea is to glue together cocycles from spaces of lower genus graphs with univalent vertices. Parts of this talk are based on recent joint work with J. Conant, A. Hatcher and M. Kassabov.

This talk is part of the Differential Geometry and Topology Seminar series.

This talk is included in these lists:

Note that ex-directory lists are not shown.

Other lists

Room GS15 at the William Gates Building and on Zoom: https://cl-cam-ac-uk.zoom.us/j/4361570789?pwd=Nkl2T3ZLaTZwRm05bzRTOUUxY3Q4QT09&from=addon Seminar Rooms 3 & 4, Churchill College sureapks

Other talks

The rise of local cartography in Europe, 12th-14th century Title TBC Chemical strategies for biomolecule functionalisation, and biomaterial conjugation Group Presentation 2 Ensemble inequivalence for systems with long-range interactions Title and abstract tba
 

Š 2006-2025 Talks.cam, University of Cambridge. Contact Us | Help and Documentation | Privacy and Publicity