Difference between revisions of "Geometry and Topology Seminar"

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The [[Geometry and Topology]] seminar meets in room '''901 of Van Vleck Hall''' on '''Fridays''' from '''1:20pm - 2:10pm'''.
 
The [[Geometry and Topology]] seminar meets in room '''901 of Van Vleck Hall''' on '''Fridays''' from '''1:20pm - 2:10pm'''.
 
<br>  
 
<br>  
For more information, contact [http://www.math.wisc.edu/~kjuchukova Alexandra Kjuchukova] or [https://sites.google.com/a/wisc.edu/lu-wang/ Lu Wang] .
+
For more information, contact Shaosai Huang.
  
 
[[Image:Hawk.jpg|thumb|300px]]
 
[[Image:Hawk.jpg|thumb|300px]]
  
== Fall 2016 ==
 
  
 +
== Spring 2019 ==
 
{| cellpadding="8"
 
{| cellpadding="8"
 
!align="left" | date
 
!align="left" | date
Line 13: Line 13:
 
!align="left" | host(s)
 
!align="left" | host(s)
 
|-
 
|-
|September 9
+
|April 5
| [http://www.math.wisc.edu/~bwang/ Bing Wang] (UW Madison)
+
|Mark Pengitore (Ohio)
| [[#Bing Wang| "The extension problem of the mean curvature flow"]]
+
|TBA
| (Local)
+
|(Dymarz)
|-
+
 
|September 16
 
| [http://www.math.northwestern.edu/~weinkove/ Ben Weinkove] (Northwestern University)
 
| [[#Ben Weinkove| "Gauduchon metrics with prescribed volume form"]]
 
| Lu Wang
 
|-
 
|September 23
 
| Jiyuan Han (UW Madison)
 
| [[#Jiyuan Han| "Deformation theory of scalar-flat ALE Kahler surfaces"]]
 
| (Local)
 
|-
 
|September 30
 
|
 
|
 
|
 
|-
 
|October 7
 
| Yu Li (UW Madison)  
 
| [[#Yu Li| "Ricci flow on asymptotically Euclidean manifolds"]]
 
| (Local)
 
|-
 
|October 14
 
| [http://math.uchicago.edu/~seanpkh/ Sean Howe] (University of Chicago)
 
| [[#Sean Howe| "Representation stability and hypersurface sections"]]
 
| Melanie Matchett Wood
 
|-
 
|October 21
 
| [https://sites.google.com/site/mathnanli/ Nan Li] (CUNY)
 
| [[#Nan Li| "Quantitative estimates on the singular Sets of Alexandrov spaces"]]
 
| Lu Wang
 
|-
 
|October 28
 
| Ronan Conlon(Florida International University)
 
| [[#Ronan Conlon| "New examples of gradient expanding K\"ahler-Ricci solitons"]]
 
| Bing Wang
 
|-
 
|November 4
 
| Jonathan Zhu (Harvard University)
 
| [[#Jonathan Zhu| "Entropy and self-shrinkers of the mean curvature flow"]]
 
| Lu Wang
 
|-
 
|November 11
 
| Canceled.
 
|
 
|
 
|-
 
|November 18
 
| [http://www.math.uiuc.edu/~cuyanik2/ Caglar Uyanik] (Illinois)
 
| [[#Caglar Uyanik| "Geometry and dynamics of free group automorphisms"]]
 
| [http://www.math.wisc.edu/~rkent Kent]
 
|-
 
| Thanksgiving Recess
 
|
 
|
 
|
 
|-
 
|December 2
 
|Peyman Morteza (UW Madison)
 
| [[#Peyman Morteza| "Gluing construction of Einstein manifolds"]]
 
| (Local) 
 
|-
 
|December 9
 
| Yu Zeng(University of Rochester)
 
|  [[#Yu Zeng| "Short time existence of the Calabi flow with rough initial data"]]
 
| Bing Wang
 
|
 
|-
 
|December 16
 
|(No seminar)
 
|
 
|-
 
|
 
 
|}
 
|}
 
+
== Fall 2018 ==
== Spring 2017 ==
 
  
 
{| cellpadding="8"
 
{| cellpadding="8"
Line 99: Line 27:
 
!align="left" | host(s)
 
!align="left" | host(s)
 
|-
 
|-
|Jan 20
+
|Sept. 14
| [http://people.mpim-bonn.mpg.de/rovi/ Carmen Rovi] (University of Indiana Bloomington)
+
|Teddy Einstein (UIC)
| [[#Carmen Rovi| "The mod 8 signature of a fiber bundle"]]
+
|Quasiconvex Hierarchies for Relatively Hyperbolic Non-Positively Curved Cube Complexes
| Maxim
+
|(Dymarz)
|-
 
|Jan 27
 
 
|
 
|
 
|-
 
|Feb 3
 
| Rafael Montezuma (University of Chicago)  
 
| [[#Rafael Montezuma| "TBA"]]
 
| Lu Wang
 
|-
 
|Feb 10
 
 
|
 
|
 
|-
 
|Feb 17
 
|[http://www.math.northwestern.edu/~hartman/ Yair Hartman] (Northwestern University) 
 
|[[#Yair Hartman| "Intersectional Invariant Random Subgroups and Furstenberg Entropy."]]
 
| [http://www.math.wisc.edu/~dymarz Dymarz]
 
|-
 
|Feb 24
 
| [http://math.uchicago.edu/~lambrozio/ Lucas Ambrozio] (University of Chicago)
 
| [[#Lucas Ambrozio| "TBA"]]
 
| Lu Wang
 
|-
 
|March 3
 
| [http://www.math.uqam.ca/~powell/ Mark Powell] (Université du Québec à Montréal)
 
| [[#Mark Powell| "TBA"]]
 
| Kjuchukova
 
|-
 
|March 10
 
| [http://www.math.wisc.edu/~kent Autumn Kent] (Wisconsin)
 
| [[#Autumn Kent | ''Analytic functions from hyperbolic manifolds'']]
 
| local
 
 
|-
 
|-
|March 17
+
|Oct. 12
|  
+
|Marissa Loving
|  
+
|Least dilatation of pure surface braids
|  
+
|(Kent)
 
|-
 
|-
|March 24
+
|Oct. 19
| Spring Break
+
|Sara Maloni
|  
+
|On type-preserving representations of thrice punctured projective plane group
|  
+
|(Kent)
 
|-
 
|-
|March 31
+
|Oct. 26
| [http://www.math.uci.edu/~xiangwen/ Xiangwen Zhang] (University of California-Irvine)
+
|Dingxin Zhang (Harvard-CMSA)
| [[#Xiangwen Zhang| "TBA"]]
+
|Relative cohomology and A-hypergeometric equations
| Lu Wang
+
|(Huang)
|  
 
 
|-
 
|-
|April 7
+
|Nov. 9
|
+
|Zhongshan An (Stony Brook)
|  
+
|Ellipticity of the Bartnik Boundary Conditions
|  
+
|(Huang)
 
|-
 
|-
|April 14
+
|Nov. 16
| [https://www.math.wisc.edu/~gong/ Xianghong Gong] (Wisconsin)
+
|Xiangdong Xie
| [[#Xianghong Gong| "TBA"]]
+
|Quasi-isometric rigidity of a class of right angled Coxeter groups
| local
+
|(Dymarz)
|-
 
|April 21
 
|[http://www.math.csi.cuny.edu/~maher/ Joseph Maher] (CUNY) 
 
| [[#Joseph Maher|"TBA"]]
 
| [http://www.math.wisc.edu/~dymarz Dymarz]
 
|-
 
|April 28
 
| [http://bena-tshishiku.squarespace.com/ Bena Tshishiku] (Harvard)
 
| [[#Bena Tshishiku| "TBA"]]
 
| [http://www.math.wisc.edu/~dymarz Dymarz]
 
 
|-
 
|-
 
|
 
|
Line 180: Line 62:
 
== Fall Abstracts ==
 
== Fall Abstracts ==
  
=== Ronan Conlon ===
+
===Teddy Einstein===
''New examples of gradient expanding K\"ahler-Ricci solitons''
 
 
 
A complete K\"ahler metric $g$ on a K\"ahler manifold $M$ is a \emph{gradient expanding K\"ahler-Ricci soliton} if there exists a smooth real-valued function $f:M\to\mathbb{R}$ with $\nabla^{g}f$ holomorphic such that $\operatorname{Ric}(g)-\operatorname{Hess}(f)+g=0$. I will present new examples of such metrics on the total space of certain holomorphic vector bundles. This is joint work with Alix Deruelle (Universit\'e Paris-Sud).
 
 
 
 
 
=== Jiyuan Han ===
 
''Deformation theory of scalar-flat ALE Kahler surfaces''
 
 
 
We prove a Kuranishi-type theorem for deformations of complex structures on ALE Kahler surfaces. This is used to prove that for any scalar-flat Kahler ALE surfaces, all small deformations of complex structure also admit scalar-flat Kahler ALE metrics. A local moduli space of scalar-flat Kahler ALE metrics is then constructed, which is shown to be universal up to small diffeomorphisms (that is, diffeomorphisms which are close to the identity in a suitable sense). A formula for the dimension of the local moduli space is proved in the case of a scalar-flat Kahler ALE surface which deforms to a minimal resolution of \C^2/\Gamma, where \Gamma is a finite subgroup of U(2) without complex reflections. This is a joint work with Jeff Viaclovsky.
 
 
 
=== Sean Howe ===
 
''Representation stability and hypersurface sections''
 
 
 
We give stability results for the cohomology of natural local systems on spaces of smooth hypersurface sections as the degree goes to \infty. These results give new geometric examples of a weak version of representation stability for symmetric, symplectic, and orthogonal groups. The stabilization occurs in point-counting and in the Grothendieck ring of Hodge structures, and we give explicit formulas for the limits using a probabilistic interpretation. These results have natural geometric analogs -- for example, we show that the "average" smooth hypersurface in \mathbb{P}^n is \mathbb{P}^{n-1}!
 
  
=== Nan Li ===
+
"Quasiconvex Hierarchies for Relatively Hyperbolic Non-Positively Curved Cube Complexes"
''Quantitative estimates on the singular sets of Alexandrov spaces''
 
  
The definition of quantitative singular sets was initiated by Cheeger and Naber. They proved some volume estimates on such singular sets in non-collapsed manifolds with lower Ricci curvature bounds and their limit spaces. On the quantitative singular sets in Alexandrov spaces, we obtain stronger estimates in a collapsing fashion. We also show that the (k,\epsilon)-singular sets are k-rectifiable and such structure is sharp in some sense. This is a joint work with Aaron Naber.  
+
Non-positively curved (NPC) cube complexes are important tools in low dimensional topology and group theory and play a prominent role in Agol's proof of the Virtual Haken Conjecture. Constructing a hierarchy for a NPC cube complex is a powerful method of decomposing its fundamental group essential to the theory of NPC cube complex theory. When a cube complex admits a hierarchy with nice properties, it becomes possible to use the hierarchy structure to make inductive arguments. I will explain what a quasiconvex hierarchy of an NPC cube complex is and briefly discuss some of the applications. We will see an outline of how to construct a quasiconvex hierarchy for a relatively hyperbolic NPC cube complex and some of the hyperbolic and relatively hyperbolic geometric tools used to ensure the hierarchy is indeed quasiconvex.
  
=== Yu Li ===
+
===Marissa Loving===
  
In this talk, we prove that if an asymptotically Euclidean (AE) manifold with nonnegative scalar curvature has long time existence of Ricci flow, it converges to the Euclidean space in the strong sense. By convergence, the mass will drop to zero as time tends to infinity. Moreover, in three dimensional case, we use Ricci flow with surgery to give an independent proof of positive mass theorem. A classification of diffeomorphism types is also given for all AE 3-manifolds with nonnegative scalar curvature.
+
"Least dilatation of pure surface braids"
  
=== Peyman Morteza ===
+
The n-stranded pure surface braid group of a genus g surface can be described as the subgroup of the pure mapping class group of a surface of genus g with n-punctures which becomes trivial on the closed surface. I am interested in the least dilatation of pseudo-Anosov pure surface braids. For the n=1 case, upper and lower bounds on the least dilatation were proved by Dowdall and Aougab—Taylor, respectively. In this talk, I will describe the upper and lower bounds I have proved as a function of g and n.
''We develop a procedure to construct Einstein metrics by gluing the Calabi metric to an Einstein orbifold.  We show that our gluing problem is obstructed and we calculate the obstruction explicitly.  When our obstruction does not vanish, we obtain a non-existence result in the case that the base orbifold is compact. When our obstruction vanishes and the base orbifold is non-degenerate and asymptotically hyperbolic we prove an existence result. This is a joint work with Jeff Viaclovsky. ''
 
  
=== Caglar Uyanik ===
+
===Sara Maloni===
''Geometry and dynamics of free group automorphisms''
 
  
A common theme in geometric group theory is to obtain structural results about infinite groups by analyzing their action on metric spaces. In this talk, I will focus on two geometrically significant groups; mapping class groups and outer automorphism groups of free groups.We will describe a particular instance of how the dynamics and geometry of their actions on various spaces provide deeper information about the groups.
+
"On type-preserving representations of thrice punctured projective plane group"
  
=== Bing Wang ===
+
In this talk, after a brief overview on famous topological and dynamical open questions on character varieties, we will consider type-preserving representations of the fundamental group of the three-holed projective plane N into PGL(2, R). First, we prove Kashaev’s conjecture on the number of connected components with non-maximal euler class. Second, we show that for all representations with euler class 0 there is a one simple closed curve which is sent to a non-hyperbolic element, while in euler class 1 or -1 we show that there are six components where all the simple closed curves are sent to hyperbolic elements and 2 components where there are some simple closed curves sent to non-hyperbolic elements. This answers a generalisation of a question asked by Bowditch for orientable surfaces. In addition, we show, in most cases, that the action of the pure mapping class group Mod(N) on these non-maximal components is ergodic, proving Goldman conjecture in those cases. Time permitting we will discuss a work in progress with Palesi where we expend these results to all five surfaces (orientable and non-orientable) of characteristic -2. (This is joint work with F. Palesi and T. Yang.)
''The extension problem of the mean curvature flow''
 
  
We show that the mean curvature blows up at the first finite singular time for a closed smooth embedded mean curvature flow in R^3.
+
===Dingxin Zhang===
A key ingredient of the proof is to show a two-sided pseudo-locality property of the mean curvature flow, whenever the mean curvature is bounded.
+
"Relative cohomology and A-hypergeometric equations"
This is a joint work with Haozhao Li.
 
  
=== Ben Weinkove ===
+
The GKZ hypergeometric equations are closely related to the period integrals of algebraic varieties. Based on the theorems of Walther--Schulze, we identify the set of solutions of a certain GKZ system with some relative homology groups. Our result generalizes the theorem of Huang--Lian--Yau--Zhu. This is a joint work with Tsung-Ju Lee.
''Gauduchon metrics with prescribed volume form''
 
  
Every compact complex manifold admits a Gauduchon metric in each conformal class of Hermitian metrics. In 1984 Gauduchon conjectured that one can prescribe the volume form of such a metric.  I will discuss the proof of this conjecture, which amounts to solving a nonlinear Monge-Ampere type equation.  This is a joint work with Gabor Szekelyhidi and Valentino Tosatti.
 
  
=== Jonathan Zhu ===
+
===Zhongshan An===
''Entropy and self-shrinkers of the mean curvature flow''
+
"Ellipticity of the Bartnik Boundary Conditions"
  
The Colding-Minicozzi entropy is an important tool for understanding the mean curvature flow (MCF), and is a measure of the complexity of a submanifold. Together with Ilmanen and White, they conjectured that the round sphere minimises entropy amongst all closed hypersurfaces. We will review the basics of MCF and their theory of generic MCF, then describe the resolution of the above conjecture, due to J. Bernstein and L. Wang for dimensions up to six and recently claimed by the speaker for all remaining dimensions. A key ingredient in the latter is the classification of entropy-stable self-shrinkers that may have a small singular set.
+
The Bartnik quasi-local mass is defined to measure the mass of a bounded manifold with boundary, where a collection of geometric boundary data — the so-called Bartnik boundary data— plays a key role. Bartnik proposed the open problem whether, on a given manifold with boundary, there exists a stationary vacuum metric so that the Bartnik boundary conditions are realized. In the effort to answer this question, it is important to prove the ellipticity of Bartnik boundary conditions for stationary vacuum metrics. In this talk, I will start with an introduction to the Bartnik quasi-local mass and the moduli space of stationary vacuum metrics. Then I will explain the ellipticity result for the Bartnik boundary conditions and, as an application, give a partial answer to the existence question.
  
===Yu Zeng===
+
===Xiangdong Xie===
''Short time existence of the Calabi flow with rough initial data''
+
"Quasi-isometric rigidity of a class of right angled Coxeter groups"
  
Calabi flow was introduced by Calabi back in 1950’s as a geometric flow approach to the existence of extremal metrics. Analytically it is a fourth order nonlinear parabolic equation on the Kaehler potentials which deforms the Kaehler potential along its scalar curvature. In this talk, we will show that the Calabi flow admits short time solution for any continuous initial Kaehler metric. This is a joint work with Weiyong He.
+
Given any finite simplicial graph G with vertex set V  and edge set E, the associated right angled Coxeter group  (RACG)  W(G) is defined
 +
as the group with generating set V whose generators all have order 2 and where uv=vu for each edge (u,v).
 +
The classical examples are the reflection groups generated by the reflections about edges of right angled polygons (in the Euclidean plane or the hyperbolic plane). We classify a class of RACGs up to quasi-isometry. This is joint work with Jordan Bounds.
  
 
== Spring Abstracts ==
 
== Spring Abstracts ==
 
===Lucas Ambrozio===
 
"TBA"
 
 
===Rafael Montezuma===
 
"TBA"
 
 
===Carmen Rovi===
 
''The mod 8 signature of a fiber bundle''
 
 
In this talk we shall be concerned with the residues modulo 4 and modulo 8 of the signature of a 4k-dimensional geometric Poincare complex. I will explain the relation between the signature modulo 8 and two other invariants: the Brown-Kervaire invariant and the Arf invariant. In my thesis I applied the relation between these invariants to the study of the signature modulo 8 of a fiber bundle. In 1973 Werner Meyer used group cohomology to show that a surface bundle has signature divisible by 4. I will discuss current work with David Benson, Caterina Campagnolo and Andrew Ranicki where we are using group cohomology and  representation theory of finite groups to detect non-trivial signatures modulo 8 of surface bundles.
 
 
===Yair Hartman===
 
"Intersectional Invariant Random Subgroups and Furstenberg Entropy."
 
 
In this talk I'll present a joint work with Ariel Yadin, in which we solve the Furstenberg Entropy Realization Problem for finitely supported random walks (finite range jumps) on free groups and lamplighter groups. This generalizes a previous result of Bowen. The proof consists of several reductions which have geometric and probabilistic flavors of independent interests.
 
All notions will be explained in the talk, no prior knowledge of Invariant Random Subgroups or Furstenberg Entropy is assumed.
 
 
===Bena Tshishiku===
 
"TBA"
 
 
===Autumn Kent===
 
''Analytic functions from hyperbolic manifolds''
 
 
At the heart of Thurston's proof of Geometrization for Haken manifolds is a family of analytic functions between Teichmuller spaces called "skinning maps."  These maps carry geometric information about their associated hyperbolic manifolds, and I'll discuss what is presently known about their behavior.  The ideas involved form a mix of geometry, algebra, and analysis.
 
 
===Xiangwen Zhang===
 
"TBA"
 
  
 
== Archive of past Geometry seminars ==
 
== Archive of past Geometry seminars ==
 +
2017-2018 [[Geometry_and_Topology_Seminar_2017-2018]]
 +
<br><br>
 +
2016-2017  [[Geometry_and_Topology_Seminar_2016-2017]]
 +
<br><br>
 
2015-2016: [[Geometry_and_Topology_Seminar_2015-2016]]
 
2015-2016: [[Geometry_and_Topology_Seminar_2015-2016]]
 
<br><br>
 
<br><br>

Latest revision as of 17:12, 24 January 2019

The Geometry and Topology seminar meets in room 901 of Van Vleck Hall on Fridays from 1:20pm - 2:10pm.
For more information, contact Shaosai Huang.

Hawk.jpg


Spring 2019

date speaker title host(s)
April 5 Mark Pengitore (Ohio) TBA (Dymarz)

Fall 2018

date speaker title host(s)
Sept. 14 Teddy Einstein (UIC) Quasiconvex Hierarchies for Relatively Hyperbolic Non-Positively Curved Cube Complexes (Dymarz)
Oct. 12 Marissa Loving Least dilatation of pure surface braids (Kent)
Oct. 19 Sara Maloni On type-preserving representations of thrice punctured projective plane group (Kent)
Oct. 26 Dingxin Zhang (Harvard-CMSA) Relative cohomology and A-hypergeometric equations (Huang)
Nov. 9 Zhongshan An (Stony Brook) Ellipticity of the Bartnik Boundary Conditions (Huang)
Nov. 16 Xiangdong Xie Quasi-isometric rigidity of a class of right angled Coxeter groups (Dymarz)

Fall Abstracts

Teddy Einstein

"Quasiconvex Hierarchies for Relatively Hyperbolic Non-Positively Curved Cube Complexes"

Non-positively curved (NPC) cube complexes are important tools in low dimensional topology and group theory and play a prominent role in Agol's proof of the Virtual Haken Conjecture. Constructing a hierarchy for a NPC cube complex is a powerful method of decomposing its fundamental group essential to the theory of NPC cube complex theory. When a cube complex admits a hierarchy with nice properties, it becomes possible to use the hierarchy structure to make inductive arguments. I will explain what a quasiconvex hierarchy of an NPC cube complex is and briefly discuss some of the applications. We will see an outline of how to construct a quasiconvex hierarchy for a relatively hyperbolic NPC cube complex and some of the hyperbolic and relatively hyperbolic geometric tools used to ensure the hierarchy is indeed quasiconvex.

Marissa Loving

"Least dilatation of pure surface braids"

The n-stranded pure surface braid group of a genus g surface can be described as the subgroup of the pure mapping class group of a surface of genus g with n-punctures which becomes trivial on the closed surface. I am interested in the least dilatation of pseudo-Anosov pure surface braids. For the n=1 case, upper and lower bounds on the least dilatation were proved by Dowdall and Aougab—Taylor, respectively. In this talk, I will describe the upper and lower bounds I have proved as a function of g and n.

Sara Maloni

"On type-preserving representations of thrice punctured projective plane group"

In this talk, after a brief overview on famous topological and dynamical open questions on character varieties, we will consider type-preserving representations of the fundamental group of the three-holed projective plane N into PGL(2, R). First, we prove Kashaev’s conjecture on the number of connected components with non-maximal euler class. Second, we show that for all representations with euler class 0 there is a one simple closed curve which is sent to a non-hyperbolic element, while in euler class 1 or -1 we show that there are six components where all the simple closed curves are sent to hyperbolic elements and 2 components where there are some simple closed curves sent to non-hyperbolic elements. This answers a generalisation of a question asked by Bowditch for orientable surfaces. In addition, we show, in most cases, that the action of the pure mapping class group Mod(N) on these non-maximal components is ergodic, proving Goldman conjecture in those cases. Time permitting we will discuss a work in progress with Palesi where we expend these results to all five surfaces (orientable and non-orientable) of characteristic -2. (This is joint work with F. Palesi and T. Yang.)

Dingxin Zhang

"Relative cohomology and A-hypergeometric equations"

The GKZ hypergeometric equations are closely related to the period integrals of algebraic varieties. Based on the theorems of Walther--Schulze, we identify the set of solutions of a certain GKZ system with some relative homology groups. Our result generalizes the theorem of Huang--Lian--Yau--Zhu. This is a joint work with Tsung-Ju Lee.


Zhongshan An

"Ellipticity of the Bartnik Boundary Conditions"

The Bartnik quasi-local mass is defined to measure the mass of a bounded manifold with boundary, where a collection of geometric boundary data — the so-called Bartnik boundary data— plays a key role. Bartnik proposed the open problem whether, on a given manifold with boundary, there exists a stationary vacuum metric so that the Bartnik boundary conditions are realized. In the effort to answer this question, it is important to prove the ellipticity of Bartnik boundary conditions for stationary vacuum metrics. In this talk, I will start with an introduction to the Bartnik quasi-local mass and the moduli space of stationary vacuum metrics. Then I will explain the ellipticity result for the Bartnik boundary conditions and, as an application, give a partial answer to the existence question.

Xiangdong Xie

"Quasi-isometric rigidity of a class of right angled Coxeter groups"

Given any finite simplicial graph G with vertex set V and edge set E, the associated right angled Coxeter group (RACG) W(G) is defined as the group with generating set V whose generators all have order 2 and where uv=vu for each edge (u,v). The classical examples are the reflection groups generated by the reflections about edges of right angled polygons (in the Euclidean plane or the hyperbolic plane). We classify a class of RACGs up to quasi-isometry. This is joint work with Jordan Bounds.

Spring Abstracts

Archive of past Geometry seminars

2017-2018 Geometry_and_Topology_Seminar_2017-2018

2016-2017 Geometry_and_Topology_Seminar_2016-2017

2015-2016: Geometry_and_Topology_Seminar_2015-2016

2014-2015: Geometry_and_Topology_Seminar_2014-2015

2013-2014: Geometry_and_Topology_Seminar_2013-2014

2012-2013: Geometry_and_Topology_Seminar_2012-2013

2011-2012: Geometry_and_Topology_Seminar_2011-2012

2010: Fall-2010-Geometry-Topology