Department of

March 2006 April 2006 May 2006 Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 1 1 2 3 4 5 6 5 6 7 8 9 10 11 2 3 4 5 6 7 8 7 8 9 10 11 12 13 12 13 14 15 16 17 18 9 10 11 12 13 14 15 14 15 16 17 18 19 20 19 20 21 22 23 24 25 16 17 18 19 20 21 22 21 22 23 24 25 26 27 26 27 28 29 30 31 23 24 25 26 27 28 29 28 29 30 31 30

Wednesday, April 12, 2006

**Abstract:** I'll show how a kind of "open string theory" is the same as a Frobenius A-infinity algebra, and also how to construct a "closed string theory" structure on Hochschild homology of such an algebra. This implies that this Hochschild homology carries natural operations coming from the homology of moduli spaces of Riemann surface.