Past Geometry and Topology:

**Time & Location**: All talks are on Thursday in Gibson Hall 308 at 12:30 PM unless otherwise noted.

**Organizer**: Slawomir Kwasik

Mentor Stafa - Tulane University

**Abstract**: *TBA*

Jenifer Hom - Georgia Tech

**Abstract**:

The knot concordance group C consists of knots in S^3 modulo knots that bound smooth disks in B^4, with the operation induced by connected sum. We consider various generalizations of the knot concordance group, and compare these to the classical case. This is joint work with Adam Levine and Tye Lidman.

Daniel Ramras - Institution: Indiana University – Purdue University Indianapolis

**Abstract**:

Location: Gibson Hall 308

Time: 9:00 AM

Michael Kelly - Loyola University

**Abstract**:

Robin Koytcheff - University of Louisiana, Lafayette

**Abstract**:

In joint work with Rafal Komendarczyk and Ismar Volic, we study the space of braids, that is, the loop space of the configuration space of points in a Euclidean space. We relate two different integration-based approaches to its cohomology, both encoded by complexes of graphs. On the one hand, we can restrict Bott-Taubes configuration space integrals for the space of long links to the subspace of braids. On the other hand, there are integrals for configuration spaces themselves, used in Kontsevich’s proof of the formality of the little disks operad. Combining the latter integrals with the bar construction and Chen’s iterated integrals yields classes in the space of braids, extending a result of Kohno. We show that these two integration constructions are compatible by relating their respective graph complexes. As one consequence, we get that the cohomology of the space of long links surjects onto the cohomology of the space of braids.

Daciberg Goncalves - University of Sao Paulo

**Abstract**:

*We describe in detail the family of the 3-manifolds which admits geometry Sol. This description is topological in the sense that it is given in terms of bundles. We provide some recent results about these manifolds which are connected with fixed points theory. Then using a presentation for the fundamental group $G$ of the manifold, we describe a procedure to determine the group of the automorphisms of $G$. These classification of such manifolds is close related with the group $Gl(2,Z)$. We describe several properties of the group $Gl(2,Z)$ that are used to provide the results for many such matrices. For the particular case of torus bundle, which is simpler than the general case, we obtain that $Aut(G)$ is the middle term of the short exact sequence $$ 1 \arrow{r} \Aut_0(G) \arrow{r} \Aut(G) \arrow{r}{\psi} Z_2 \arrow{r} 1$$, where $ \Aut_0 (G)\cong ((Z\oplusZ)\rtimes\limits_{M_0} Z)\rtimes_{\phi} Z_2$.*

Location: Stanley Thomas 316

Time: 12:30

Speaker - Institution

**Abstract**: *TBA*

Speaker - Institution

**Abstract**: *TBA*

Speaker - Institution

**Abstract**: *TBA*

Mathematics Department, 424 Gibson Hall, New Orleans, LA 70118 504-865-5727 math@math.tulane.edu