Lecture 15: Tcft’s or String Backgrounds
نویسنده
چکیده
We will now consider TCFT’s or string backgrounds, or in other words, CFT’s with ghosts and total central charge c = 0. Consider the Segal PROP P = {Pm,n | m,n ≥ 0}, algebras over which defined CFT’s. Take the corresponding DG PROP of singular chains C•(P). The coefficients will always be complex when we talk about TCFT’s. We will give three definitions of a TCFT, gradually closer to what the physicists work with. These definitions will not be equivalent after all, this is physics! However, you can do many things equally well with all of them. The first one is really short.
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