Mdtop October 2018

mdtop@mathdept.okstate.edu

1 participants
2 discussions

Today in seminar
by Hoffman, Neil 23 Oct '18

23 Oct '18

Hello everyone, We have seminar today. Amey Kaloti will be speaking on "Embedding questions for Weinstein and contact manifolds" His title and abstract are below. Also, we will be taking Amey out for dinner tonight at hideaway. Meet at my office around 5:15 if you are interested in that. Embedding questions for Weinstein and contact manifolds. Speaker: Amey Kaloti, University of Arkansas Date: Oct 23, 2018 Time: 2:30 PM Room: MSCS 405 Abstract: We describe a framework for embedding Weinstein 4-manifolds into Weinstein 6-manifolds using Lefschetz fibrations. The process also reframes the ”spun embeddings” of Etnyre and Lekili used to describe embeddings of contact 3-manifolds into contact 5-manifolds. We’ll discuss obstructions as well as examples including Weinstein 6-manifolds which contain all Weinstein 4-manifolds as properly embedded Weinstein submanifolds. Joint work with Jeremy Van Horn-Morris. ______________________ Neil R. Hoffman Assistant Professor Department of Mathematics 523 Math Science Building Oklahoma State University Stillwater, OK 74078-1058 405-744-7791 http://math.okstate.edu/people/nhoffman

1 0

Seminar today
by Hoffman, Neil 09 Oct '18

09 Oct '18

Hello everyone, Seminar is today in 405. Nick Castro from UArk is speaking his title and abstract are below: Lefschetz Fibrations and Relative Trisections Speaker: Nickolas Castro, University of Arkansas Date: Oct 9, 2018 Time: 2:30 PM Room: MSCS 405 Abstract: A relative trisection of a smooth 4-manifold with boundary is a decomposition into three diffeomorphic, codimension zero subspaces whose pairwise intersections are 3-dimensional cobordisms, and triple intersection is a surface with boundary. Such a decomposition can be uniquely described by a collection of curves on this surface, called a relative trisection diagram. From this diagram, we can algorithmically determine the structure induced on the bounding 3-manifold(s), called an open book decomposition. A Lefschetz fibration on a smooth 4-manifold is a map which is locally a surface bundle away from its isolated critical points. Lefschetz fibrations can also be described by curves on a surface and, in the case of manifolds with boundary, also induce an open book decomposition on the boundary. In this talk, I will define these structures and discuss how to obtain a trisection from a Lefschetz fibration. I will present an alternate proof on the existence of trisection of closed 4-manifolds by way of Lefschetz fibrations and the gluing theorem. Finally, I will discuss the uniqueness of relative trisections which induce different open book decompositions. ______________________ Neil R. Hoffman Assistant Professor Department of Mathematics 523 Math Science Building Oklahoma State University Stillwater, OK 74078-1058 405-744-7791 http://math.okstate.edu/people/nhoffman

1 0

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

Mdtop October 2018