

Present>>Abstract 

Abstracts

On the PROB of Singular Braids 
BEARDSLEY, Jonathan 
University of Nevada,
Reno, USA 
Abstract:
This talk describes joint work with Suhyeon Lee (Berkeley), Brendan
Murphy (University of Washington) and Luke Trujillo (Harvey Mudd College).
I will explain the definition of a PROB, which generalizes the PROPs
of Boardman and Vogt, and give several examples. The example of
particular interest in this talk will be SB, the PROB of singular
braids. To the authors' knowledge, the category SB has not appeared
in the literature before. This PROB is the free braided monoidal category
containing an object whose nfold tensor powers admit an action of the
singular braid monoid on n strands. If time allows, I will give a
sketch of the associated braided operad of SB. A long term goal of
this research is to use this technology to give a general framework
for producing and studying invariants of singular knots and links,
which may be obtained from singular braid invariants 


Twisted bisymplectic structure of ArtinSchelter regular algebras 
CHEN, XiaoJun 
Sichuan University, China 
Abstract:
In this talk, we show that there is a twisted noncommutative symplectic structure on ASregular algebras, where the twisting comes from the Nakayama automorphism of the algebra.
This twisted symplectic structure gives an isomorphism between the derived tangent complex and the derived twisted cotangent complex of the ASregular algebra, and when taking the commutator quotient space,
we get Van den Bergh 's noncommutative Poincare duality. This talk is based on an ongoing research joint with Eshmatov and Liu.



Some results on Poisson algebras and NovikovPoisson algebras 
CHEN, YuQun 
South China Normal University, China 

Abstract:
A Poisson algebra is a vector space
$\mathcal{A}$
over a field $\Bbbk$ endowed with two bilinear operations, a multiplication denoted by $x\otimes y \mapsto x\cdot y$ and a Poisson bracket denoted by $x\otimes y \mapsto (x, y)$, such that
$(\mathcal{A}, \cdot)$ is a commutative associative algebra, $(\mathcal{A}, (, )$ is a Lie algebra, and $\mathcal{A}$ satisfies the Leibniz identity
\[(x, y\cdot z)=(x, y)\cdot z+y\cdot (x, z).\]
We develop a new theory of GröbnerShirshov bases for Poisson algebras, which requires introducing several nontrivial new techniques.
As an application, we solve the word problem for certain one relator Poisson algebras when the leading monomial of the single relation is a Lie monomial.
A
Novikov algebra $(\mathcal{A}, \circ)$ is a vector space with the identities
\[x\circ (y\circ z)(x\circ y)\circ z
=
y\circ (x\circ z)(y\circ x)\cirx z) (left symmetry),\]
\[(x\circ y)\circ z = (x\circ z) \circ y (right commutativity).\]
A NovikovPoisson algebra
$(\mathcal{A}, \cdot, \circ)$ is a vector space with two bilinear operations
"$\cdot$" and
"$\circ$" such that $(\mathcal{A}, \circ)$ forms a Novikov algebra,
$
(\mathcal{A}, \cdot)$ forms a commutative associative algebra,
and the following two identities holds:
\[(x \cdot y) \circ z = x \cdot (y \circ z),\]
\[(x \circ y) \cdot z x \circ (y \cdot z) = (y \circ x) \cdot z y \circ (x \cdot z).\]
We construct a linear basis for a free NovikovPoisson algebra when the algebra has a unit with respect to the commutative and associative bilinear operation.
Finally, we show that every Novikov Poisson algebra (with unit) can be embedded into its universal enveloping special NovikovPoisson admissible algebra.



GTShadows and their
action on Grothendieck's child's drawings 
DOLGUSHEV, Vasily 
Temple University, USA 
Abstract:
The absolute Galois group of the field of rational numbers and the GrothendieckTeichmueller group introduced by V. Drinfeld in 1990 are among the most mysterious objects in mathematics.
My talk will be devoted to GTshadows. These tantalizing objects may be thought of as
"approximations'' to elements of the mysterious GrothendieckTeichmueller group. They form a groupoid and act on Grothendieck's child's drawings. Currently, the most amazing discovery related to GTshadows is that the orbits of child's drawings with respect to the action of the absolute Galois group (when they can be computed) and the orbits of child's drawings with respect to the action of GTshadows coincide! If time permits, I will show how to work with the software package for GTshadows and their action on child's drawings.
My talk is partially based on the joint paper https://arxiv.org/abs/2008.00066 with Le and Aidan A. Lorenz.



Rota's classication problem for nonsymmetric operads 
GUO, Li 
Rutgers
University, USA 
Abstract:
Recently, Rota's Classication Problem on algebraic operator identities has been studied in the context of GrobnerShirshov bases and rewriting systems,
giving an equivalence of the Classication Problems with the existence of the GröbnerShirshov bases and the convergence of the corresponding rewriting system, all for associative algebras with a linear operator.
In this talk, we discuss the generalization of Rota's Classication Problem to general algebraic structures, namely operads, in particular nonsymmetric operads.
This approach also allows us to study (disconnected) operads from the viewpoint of the Classication Problem. Applications to Koszulity of operads are obtained.


Recent developments in the theory of higher properads 
HACKNEY, Philip 
University of Louisiana at Lafayette,
USA 
Abstract:
Properads are gadgets that are more expressive than operads, which are capable of modeling some types of bialgebras while still admitting a satisfactory theory of Koszul duality. The focus of this talk will be on a corresponding homotopy coherent notion, that of infinity properads. In particular, we will give a concrete model for these, and discuss methods for enrichment in monoidal categories and a model for (bi)algebras. This talk is based on joint work with Hongyi Chu, and with Marcy Robertson and Donald Yau. 


Regularized Integrals over configuration spaces of Riemann surfaces 
LI, Si

Tsinghua University, China 
Abstract:
Integrals over configuration spaces arise naturally from quantum field theories and provide links between algebra and geometry. For example, topological QFT on the circle leads to an algebraic analogue of index theorem; topological
QFT on the disk leads to Kontsevich's Formality Theorem on deformation quantization. In this talk, we introduce the notion of regularized integral to formulate an analytic theory for integrals over configuration spaces of Riemann surfaces that come from 2d chiral QFT.
An an application, we explain how such regularized integrals lead geometrically to modular forms and are related to certain chiral analogue of index theorem. This is joint work with Jie Zhou. Preprint available at arXiv:2008.07503. 


GelfandKirillov dimension of nonsymmetric operads 
QI, ZiHao

East China Normal University, China 
Abstract:
In this talk, we investigate GKdimension of nonsymmetric operads and prove that the GK dimension of a nonsymmetric operad falls into {0, 1} ∪ [2, ∞); this is a generalisation to nonsymmetric operads of the Bergman Gap Theorem for associative algebras. This is a joint work with Yongjun Xu, James
J. Zhang and Xiangui Zhao. 


Which homotopy algebras come from transfer? 
ROGERS, Chris 
University of Nevada, Reno, USA 
Abstract:
Suppose $(A,d_A,\{\mu_k\})$ is an $A_\infty$algebra over a commutative ring $R$, whose underlying chain complex $(A,d_A)$ is a deformation retract of a complex $(C,d_C)$.
It is a result of Kontsevich and Soibelman that the retract data allows one to explicitly transfer the $A_\infty$structure from $(A,d_A)$ to a homotopy equivalent $A_\infty$structure on $(C,d_C)$.
In this talk, I will answer a question recently posed by Dennis Sullivan concerning the characterization of transferred structures for algebras over a suitable class of operads.
For the deformation retract scenario presented above, Sullivan's question can be stated as follows: Can one characterize, up to equivalence, the transferred structure as the unique $A_\infty$structure on $C$ whose restriction to $A$ is the original $(A,d_A,\{\mu_k\})$?
This is based on joint work arXiv:2006.00072 with Martin Markl. 


BakerCampbellHausdorff formula revisited 
SUN, ShanZhong 
Capital Normal
University, China 
Abstract:
BakerCampbellHausdorff (BCH) formula and several variants in Lie theory can be obtained through mould calculus which also gives easily the generalizations. I will give a brief introduction to mould theory and the proofs of BCH formula and some related formulas. The talk is based on joint work with Yong LI (Chern Institute, Tianjin) and David SAUZIN (IMCCE, Paris). 


Deformations and homotopy theory of relative RotaBaxter Lie algebras 
TANG, Rong 
Jilin University, China 
Abstract:
We determine the $L_\infty$algebra that controls deformations of a relative RotaBaxter Lie algebra and show that it is an extension of the dg Lie algebra controlling deformations of the underlying LieRep pair by the dg Lie algebra controlling
deformations of the relative RotaBaxter operator. Consequently, we define the cohomology of relative RotaBaxter Lie algebras and relate it to their infinitesimal deformations. A large class of relative RotaBaxter Lie algebras is obtained from triangular
Lie bialgebras and we construct a map between the corresponding deformation complexes. Next, the notion of a homotopy relative RotaBaxter Lie algebra is introduced. We show that a class of homotopy relative RotaBaxter Lie algebras is intimately related
to preLie1algebras. This is a joint work with Andrey Lazarev and Yunhe Sheng. 


Homotopy embedding tensor 
XIANG, MaoSong 
Huazhong University of Science and Technology, China 
Abstract:
The embedding tensor formalism is a powerful tool in gauged supergravity theory. Each embedding tensor gives rise to a Leibniz algebra structure on the eld content. \
We consider its homotopy counterpart which we call homotopy embedding tensor to a dierential graded Lie algebra. It turns out that there associates functorially a homotopy Leibniz algebra to each homotopy class of homotopy embedding tensors.
We will explain how to obtain a homotopy Leibniz algebra from a homotopy embedding tensor via a summation over labelled rooted forests. This is a joint work Zhuo Chen and Huabin Ge. 









