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Feb 3, 2020 at 12:44 comment added Bertram Arnold Any difference to established conventions is completely due to my own ignorance, and it is definitely bad notation to use the same letters for a complex and its cohomology. I've edited the answer as per your suggestion.
Feb 3, 2020 at 12:44 history edited Bertram Arnold CC BY-SA 4.0
Improved notation for Hochschild complex
Feb 3, 2020 at 12:19 comment added Pedro Is it common for people to write $\mathrm{HH}^*(A)$ for the Hochschild complex of an algebra? Most if not all people I know (except those working with spectra, for example, for which THH would be generally be something you take the homotopy of) would use $C^*(A)$, or some variant thereof, for the complex, and $\mathrm{HH}^*(A)$ for the cohomology of this. Perhaps you're just using a 'topological' notation here for some reason...?
May 10, 2018 at 10:27 comment added Bertram Arnold Thanks! I tried to be detailed, but here is the short version of the story: Whenever you have a deformation problem, you should first try to understand the corresponding formal deformation problem, which is governed by some dgla. If this dgla is formal, a deformation to all orders is uniquely determined by its first-order deformation, which has to be unobstructed. So a deformation of $\Lambda^*V$ "is" a Poisson structure on $\Pi V^\vee$, of which $\operatorname{Sym}^2(V)$ is a special example. The other answer gives the explicit formula for the multiplication in terms of the Poisson bracket.
May 9, 2018 at 20:03 vote accept fosco
May 9, 2018 at 20:03 comment added fosco This is a fascinating answer and it will take me "several years of Sundays" to understand it :-)
May 7, 2018 at 13:08 history answered Bertram Arnold CC BY-SA 4.0