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5 votes
0 answers
134 views

Transferred $L_\infty$-structure from Hochschild dgLA

Let $D_{poly}$ be the differential graded Lie algebra (dgLA) of differentiable Hochschild cochains on a manifold $\mathscr M$, endowed with the usual Gerstenhaber bracket $[-,-]_G$ and Hochschild ...
thingsthatmighthavebeen's user avatar
5 votes
1 answer
525 views

Motivating quantum groups from knot invariants

Quantum groups are useful for making knot/link invariants: for example, $U_q(\mathfrak{sl}_2$) you get the Jones polynomial. This boils down to the fact that $\mathcal C = \operatorname{rep }U_q(\...
Steve's user avatar
  • 2,283
1 vote
1 answer
158 views

Is the map in Kontsevich Formality Theorem $\mathcal{O}$-linear?

$X$ is smooth Poisson. Kontsevich formality theorem says that there is a $L_\infty$ quasi-isomorphism $$T_{\text{poly}}\xrightarrow{L_\infty}D_{\text{poly}},$$ where $T_{\text{poly}}:=(\bigwedge^\...
FunctionOfX's user avatar
7 votes
2 answers
386 views

Non-associative deformation quantization

Several physicists consider non-Poisson bivectors but still apply Kontsevich formality in order to get deformation quantization type results: see e.g. Szabos's review An introduction to nonassociative ...
Jim Stasheff's user avatar
  • 3,880
5 votes
0 answers
198 views

Analogue of Kontsevich's formality theorem for quantization of Courant algebroids

In his 1997 preprint, M. Kontsevich proved the formality of the differential graded algebra controlling deformations of the associative and commutative algebra of functions on a manifold, seen as an ...
thingsthatmighthavebeen's user avatar
1 vote
1 answer
199 views

How to compute the deformation quantizations of a polynomial Poisson algebra?

As a specialist told me, given a smooth affine Poisson algebra $S$ over $\mathbb{C}$, up to a choice of certain characteristic class, one can find one of the deformation quantizations of $S$, say $A$, ...
motivique's user avatar
4 votes
1 answer
423 views

Formality of the little $n$-disks operad and deformation theory

In [Another proof of M. Kontsevich formality theorem], Tamarkin provides a proof of the formality of the differential graded Lie algebra controlling the deformation of a polynomial associative algebra....
thingsthatmighthavebeen's user avatar
3 votes
1 answer
365 views

Brace algebra structure on the Hochschild complex of an associative algebra

As shown by Gerstenhaber and Voronov [Higher operations on the Hochschild complex], the Hochschild complex of an associative algebra is endowed with a natural structure of brace algebra. The first ...
thingsthatmighthavebeen's user avatar
4 votes
0 answers
220 views

What does "control of a deformation problem" mean?

Is the expression "control of a deformation problem' ever defined? There are of course many examples relating a dg-Lie or L-infty algebra to a deformation problem, and the phrase is evocative. Is it ...
Jim Stasheff's user avatar
  • 3,880
8 votes
0 answers
463 views

On the cohomology of Kontsevich graph complex

Kontsevich's formality theorem asserts that a certain quasi-isomorphism of chain complexes between the graded Lie algebra of polyvector fields on $\mathbb{R}^n$ and the dg Lie algebra of ...
Sinan Yalin's user avatar
  • 1,609
4 votes
1 answer
147 views

Equivalence of star products on two differents Poisson algebras?

Let $A$, $B$ be two commutative and associative $\mathbb k$-algebras and let $A_\hbar:=A[[\hbar]]$, $B_\hbar:=B[[\hbar]]$ be the corresponding ring of formal series. Of sense [Deformation theory and ...
MMa's user avatar
  • 53
7 votes
2 answers
688 views

Alternative to Kontsevich formality

Has anyone considered an alternative approach to Kontsevich formality in which the DGLA of poly-vector fields is deformed to an $L_\infty$-algebra? Some vocabulary: DGLA = Differential Graded Lie ...
Jim Stasheff's user avatar
  • 3,880
7 votes
1 answer
1k views

What's the relation between the heat kernel proof of the index theorem and deformation quantization?

In the book "Heat kernels and Dirac operators", I found the slogan by Quillen in the Introduction: "Dirac operators are a quantization of the theory of connections, and the supertrace of the heat ...
Zhaoting Wei's user avatar
  • 9,019
5 votes
4 answers
532 views

Non-Drinfeld–Jimbo deformations and finite quantum groups

As is well-known, for the compact semi-simple Lie groups $G$, there exist non-commutative Hopf algebra deformations ${\cal O}_q[G]$ of their coordinate algebras ${\cal O}[G]$, the so-called Drinfeld--...
Antonio Nogueria's user avatar
3 votes
1 answer
193 views

Koszul algebras deformations

Do we know the maximal class of Koszul algebras for which any deformation is Koszul?
Jim Stasheff's user avatar
  • 3,880
1 vote
1 answer
119 views

Zero Sums in a $q$-Deformation Remain Zero for $q=1$

Looking at previous question, I begun to think and came upon the following more solid question: Let $SU_q(N)$ be the usual quantized coordinated algebra of $SU(N)$. Now consider, for some fixed value ...
Ago Szekeres's user avatar
0 votes
1 answer
126 views

Deformations and Dimensions: $q$-Deform Finite to Infinite?

Let $A$ be a (complex) (finitely generated) algebra with some type of $q$-deformation $A_q$, where $A_1 = A$. Moreover, let $V_q$ be a vector subspace of $A_q$, such that $V_1$ is a finite-...
Dyke Acland's user avatar
  • 1,479
7 votes
0 answers
182 views

Deformation of Noether's first theorem

Noether's first variational theorem establishes a correspondence between symmetries and invariants. I would like to know what has been written on the following question: How do the invariants deform ...
Jim Stasheff's user avatar
  • 3,880
10 votes
3 answers
2k views

In the dictionary between Poisson and Quantum, what corresponds to Coisotropic?

I work entirely over a field of characteristic $0$, in case it matters. Recall that a Poisson algebra is a commutative algebra $A$ with a bracket $\lbrace,\rbrace : A^{\wedge 2} \to A$ which is (1) a ...
Theo Johnson-Freyd's user avatar
11 votes
1 answer
1k views

Kontsevich's formality theorem from an explicit homotopy

Suppose that $X$ is a smooth manifold, whose $C^{\infty}$-functions we denote by $A$. Let $D_{poly}^*(A):=\bigoplus_{n\geq -1}Hom(A^{\otimes n+1},A)$ be the Lie algebra of polydifferential operators ...
Jeremy Pecharich's user avatar
5 votes
3 answers
2k views

Differential Hochschild Cohomology, general tools?

Background: in deformation quantization one wants to construct formal associative deformations (the star products $\star$) of the algebra of smooth complex-valued functions on a Poisson manifold $M$ ...
Stefan Waldmann's user avatar
18 votes
2 answers
2k views

Why do my quantum group books avoid homotopical language?

I am sitting on my carpet surrounded by books about quantum groups, and the only categorical concept they discuss are the representation categories of quantum groups. Many notes closer to "Kontsevich ...
olli_jvn's user avatar
  • 904