Skip to main content

Questions tagged [a-infinity-algebras]

For questions about $A_\infty$-algebras as introduced by Stasheff in 1963 and related structures.

Filter by
Sorted by
Tagged with
16 votes
2 answers
3k views

Smooth dg algebras (and perfect dg modules and compact dg modules)

Katzarkov-Kontsevich-Pantev define a smooth dg ($\mathbb{C}$-)algebra $A$ to be a dg algebra which is a perfect $A \otimes A^{op}$-module. They say that an $A$-module $M$ is perfect if the functor $...
Kevin H. Lin's user avatar
17 votes
1 answer
2k views

Is there a refinement of the Hochschild-Kostant-Rosenberg theorem for cohomology?

The HKR theorem for cohomology in characteristic zero says that if $R$ is a regular, commutative $k$ algebra ($char(k) = 0$) then a certain map $\bigwedge^* Der(R) \to CH^*(R,R)$ (where $\wedge^* Der(...
Ian Shipman's user avatar
  • 1,038
33 votes
8 answers
5k views

triangulated vs. dg/A-infinity

Someone recently said "derived/triangulated categories are an abomination that should struck from the earth and replaced with dg/A-infinity versions". I have a rough idea why this is true ("don't ...
Kevin Walker's user avatar
  • 12.8k
13 votes
4 answers
4k views

Definition of Hochschild (co)homology of a (dg or A-infinity) category

How do you define the Hochschild (co)homology of a dg category or an A-infinity category? I've only seen it defined when the category is equivalent to a category of modules over a dg algebra; then the ...
Kevin H. Lin's user avatar
10 votes
2 answers
1k views

What's the sense in which A_\infty algebras are "deformable"?

I realise this is a very vague question! I've heard people say that A∞ algebras are the right homotopy-theoretic generalization of usual associative algebras, because you can deform them. What ...
Kim Morrison's user avatar
  • 7,800

1 2
3