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Aug 5, 2010 at 3:52 comment added Anton Kapustin Rozansky-Witten model for a compact hyperkahler target space (e.g. K3 surface) is an example of a non-semi-simple 3d TQFT. Z(S^1) is the 2-periodic derived category of coherent sheaves on the target.
Oct 13, 2009 at 16:31 comment added Chris Schommer-Pries I took a look at this book, and it did seem to me that they form a sort of TQFT (with "exotic anomaly") out of non-semisimple MTCs. The anomaly they use is "exotic" (my word) and corresponds to a central extension of the bordism 2-category, not by a group but by a monoid (I think it was the natural numbers). This way they can get a weird TQFT where the value of, say, S<sup>1</sup> x S<sup>2</sup> is zero. (This can't happen in a usual TQFT without this anomaly since the value of S<sup>1</sup> x S<sup>2</sup> is the trace of the identity. )
Oct 13, 2009 at 14:33 comment added Noah Snyder You're probably right that that only works for closed things. What about the book "Non-semisimple topological quantum field theories for 3-manifolds with corners"?
Oct 13, 2009 at 11:51 comment added Kevin H. Lin "there are known non-semisimple TQFTs" -- What's the definition of semisimple here?
Oct 13, 2009 at 7:03 comment added Kevin Walker I thought Virelizier's stuff was just for closed 3-manifolds. I would be (happily) surprised if someone had worked out a non-semisimple example which gave a functor on 3-dimensional bordisms and was well-behaved axiomatically.
Oct 13, 2009 at 6:03 history answered Noah Snyder CC BY-SA 2.5