https://www.math.wisc.edu/wiki/index.php?title=Special:NewPages&feed=atom&hideredirs=1&limit=50&offset=&namespace=0&username=&tagfilter=UW-Math Wiki - New pages [en]2020-01-23T13:10:59ZFrom UW-Math WikiMediaWiki 1.30.1https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTSpring2020NTS ABSTRACTSpring20202020-01-22T18:16:17Z<p>Shusterman: Created page with "Return to [https://www.math.wisc.edu/wiki/index.php/NTS ] == Jan 23 == <center> {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspa..."</p>
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<div>Return to [https://www.math.wisc.edu/wiki/index.php/NTS ]<br />
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== Jan 23 ==<br />
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<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#F0A0A0" align="center" style="font-size:125%" | '''Rahul Krishna'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | A relative trace formula comparison for the global Gross-Prasad conjecture for orthogonal groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
The global Gross-Prasad conjecture (really its refinement by Ichino and Ikeda) is a remarkable conjectural formula generalizing Waldspurger's formula for the central value of a Rankin-Selberg $L$ function. I will explain a relative trace formula approach to this conjecture, akin in spirit to the successful comparison for unitary groups. The approach relies on a somewhat strange matching of orbits, and on two local conjectures of smooth transfer and fundamental lemma type, which I will formulate. If time permits, I will discuss some recent evidence for these local identities in some low rank cases.<br />
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|} <br />
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<br></div>Shustermanhttps://www.math.wisc.edu/wiki/index.php/SIAM_Student_Chapter_Seminar/Fall2019SIAM Student Chapter Seminar/Fall20192020-01-21T20:17:40Z<p>Nagreen: Created page with "__NOTOC__ *'''When:''' Most Friday at 11:30am *'''Where:''' 901 Van Vleck Hall *'''Organizers:''' [http://www.math.wisc.edu/~xshen/ Xiao Shen] *'''Faculty advisers:''' [http:..."</p>
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<div>__NOTOC__<br />
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*'''When:''' Most Friday at 11:30am<br />
*'''Where:''' 901 Van Vleck Hall<br />
*'''Organizers:''' [http://www.math.wisc.edu/~xshen/ Xiao Shen]<br />
*'''Faculty advisers:''' [http://www.math.wisc.edu/~jeanluc/ Jean-Luc Thiffeault], [http://pages.cs.wisc.edu/~swright/ Steve Wright] <br />
*'''To join the SIAM Chapter mailing list:''' email [join-siam-chapter@lists.wisc.edu].<br />
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<br><br />
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== Fall 2019 ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
|-<br />
|Sept. 27, Oct. 4 <br />
|[http://www.math.wisc.edu/~xshen/ Xiao Shen] (Math)<br />
|''[[#Sep 27, Oct 4: Xiao Shen (Math)|The corner growth model]]''<br />
|-<br />
|-<br />
|Oct. 18 <br />
|[https://scholar.google.com/citations?user=7cVl9IkAAAAJ&hl=en Bhumesh Kumar] (EE)<br />
|''[[#Oct 18: Bhumesh Kumar (EE)|Non-stationary Stochastic Approximation]]''<br />
|<br />
|-<br />
|-<br />
|Oct. 25 <br />
|Max (Math)<br />
|''[[#Oct 25: Max (Math)|Coalescent with Recombination]]''<br />
|<br />
|-<br />
|-<br />
|Nov. 8<br />
|Hongfei Chen (Math)<br />
|''[[#Nov 15: Hongfei Chen (Math)| Brownian swimmers in a channel]]''<br />
|<br />
|-<br />
|-<br />
|Dec. 10<br />
|[http://www.maths.manchester.ac.uk/~higham/ Nicholas J. Higham] (University of Manchester)<br />
|''[[#Dec 10: Nicholas J. Higham (University of Manchester)|Scientific Writing]]''<br />
|-<br />
|-<br />
|<br />
|}<br />
<br />
== Abstracts ==<br />
<br />
=== Sep 27, Oct 4: Xiao Shen (Math) ===<br />
'''The corner growth model'''<br />
<br />
Imagine there is an arbitrary amount of donuts attached to the integer points of Z^2. The goal is to pick an optimal up-right path which allows you to eat as much donuts as possible along the way. We will look at some basic combinatorial observations, and how specific probability distribution would help us to study this model.<br />
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=== Oct 18: Bhumesh Kumar (EE) ===<br />
'''Non-stationary Stochastic Approximation'''<br />
<br />
Abstract: Robbins–Monro pioneered a general framework for stochastic approximation to find roots of a function with just noisy evaluations.With applications in optimization, signal processing and control theory there is resurged interest in time-varying aka non-stationary functions. This works addresses that premise by providing explicit, all time, non-asymptotic tracking error bounds via Alekseev's nonlinear variations of constant formula. <br />
<br />
Reference: https://arxiv.org/abs/1802.07759 (To appear in Mathematics of Control, Signals and Systems)<br />
<br />
=== Oct 25: Max (Math) ===<br />
'''Coalescent with Recombination'''<br />
<br />
I will talk about the continuous time coalescent with mutation and recombination, with a focus on introducing key concepts related to genetic distance and evolutionary relatedness. The talk will be informal and accessible.<br />
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=== Nov 15: Hongfei Chen (Math) ===<br />
'''Brownian swimmers in a channel'''<br />
<br />
Abstract: Shape matters! I will talk about how their shapes affect their mean reversal time.<br />
<br />
=== Dec 10: Nicholas J. Higham (University of Manchester) ===<br />
'''Scientific Writing'''<br />
<br />
I will discuss various aspects of scientific writing, including<br />
<br />
• the craft of writing in general,<br />
<br />
• aspects specific to mathematical writing,<br />
<br />
• English Usage,<br />
<br />
• workflow, and<br />
<br />
• revising drafts and proofreading.<br />
<br />
Plenty of examples and links to further information will be given. I will also discuss<br />
my experiences in preparing ''Handbook of Writing for the Mathematical Sciences'' (third<br />
edition, SIAM, 2020).<br />
<br />
<br />
<br></div>Nagreenhttps://www.math.wisc.edu/wiki/index.php/NTSGrad_Spring_2020/AbstractsNTSGrad Spring 2020/Abstracts2020-01-21T19:06:16Z<p>Soumyasankar: Created page with "This page contains the titles and abstracts for talks scheduled in the Spring 2020 semester. To go back to the main GNTS page, click here. == Jan 21 =..."</p>
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<div>This page contains the titles and abstracts for talks scheduled in the Spring 2020 semester. To go back to the main GNTS page, click [[NTSGrad_Spring_2020|here.]]<br />
<br />
== Jan 21 ==<br />
<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#F0A0A0" align="center" style="font-size:125%" | '''Qiao He'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | ''Representation theory and arithmetic geometry''<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
In this talk I will talk about the relation between representation theory and arithmetic geometry. In particular, I will try to discuss several examples that connect representation theory and arithmetic geometry closely. Then if time permits, I will give a brief introduction to trace formula approach, which is the most powerful and promising tools in this field.<br />
|} <br />
</center><br />
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<br></div>Soumyasankarhttps://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2019Graduate Algebraic Geometry Seminar Fall 20192020-01-21T16:42:29Z<p>Drwagner: Created page with "''' '''When:''' Wednesdays 4:25pm '''Where:''' Van Vleck B317 Lizzie the OFFICIAL mascot of GAGS!! '''Who:''' All undergraduate and graduate..."</p>
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<div>'''<br />
'''When:''' Wednesdays 4:25pm<br />
<br />
'''Where:''' Van Vleck B317<br />
[[Image:cat.jpg|thumb|220px| | Lizzie the OFFICIAL mascot of GAGS!!]]<br />
<br />
'''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend.<br />
<br />
'''Why:''' The purpose of this seminar is to learn algebraic geometry and commutative algebra by giving and listening to talks in a informal setting. Talks are typically accessible to beginning graduate students and take many different forms. Sometimes people present an interesting paper they find. Other times people give a prep talk for the Friday Algebraic Geometry Seminar. Other times people give a series of talks on a topic they have been studying in-depth. Regardless the goal of GAGS is to provide a supportive and inclusive place for all to learn more about algebraic geometry and commutative algebra.<br />
<br />
'''How:''' If you want to get emails regarding time, place, and talk topics ('''which are often assigned quite last minute''') add yourself to the gags mailing list: gags@lists.wisc.edu. The list registration page is [https://admin.lists.wisc.edu/index.php?p=11&l=gags here].<br />
'''<br />
<br />
== Give a talk! ==<br />
We need volunteers to give talks this semester. If you're interested contact [mailto:cbooms@wisc.edu Caitlyn] or [mailto:drwagner@math.wisc.edu David], or just add yourself to the list (though in that case we might move your talk later without your permission). Beginning graduate students are particularly encouraged to give a talk, since it's a great way to get your feet wet with the material.<br />
<br />
<br />
== Being an audience member ==<br />
The goal of GAGS is to create a safe and comfortable space inclusive of all who wish to expand their knowledge of algebraic geometry and commutative algebra. In order to promote such an environment in addition to the standard expectations of respect/kindness all participants are asked to following the following guidelines:<br />
* Do Not Speak For/Over the Speaker: <br />
* Ask Questions Appropriately: <br />
<br />
==The List of Topics that we Made February 2018==<br />
<br />
On February 21st of the Month of February of The 2018th Year of the Seventh Age of The Sun, the People Present at GAGS Compiled Ye Followinge Liste of Topics They Wished to Hear Aboute:<br />
<br />
Feel free to edit the list and/or add references to learn this stuff from. Since then, we've succeeded in talking about some of these, which doesn't mean there shouldn't be another talk. Ask around or look at old semester's websites.<br />
<br />
* Schubert Calculus, aka how many lines intersect four given lines in three-dimensional space? The answer to this question is prettiest when you think about it as a problem of intersecting subvarieties in the Grassmanian. ''What is the Grassmanian, you say?'' That's probably a talk we should have every year, so you should give it!<br />
<br />
* Kindergarten GAGA. GAGA stands for Algebraic Geometry - Analytic Geometry. Serre wrote a famous paper explaining how the two are related, and you could give an exposition suitable to kindergardeners.<br />
<br />
* Katz and Mazur explanation of what a modular form is. What is it?<br />
<br />
* Kindergarten moduli of curves.<br />
<br />
* What is a dualizing sheaf? What is a dualizing complex? What is Serre duality? What is local duality? Can local duality help us understand Serre duality?<br />
<br />
* Generalizations of Riemann - Roch. (Grothendieck - Riemann - Roch? Hirzebruch - Riemann - Roch?)<br />
<br />
* Hodge theory for babies<br />
<br />
* What is a Néron model?<br />
<br />
* What is a crystal? What does it have to do with D-modules? [http://www.math.harvard.edu/~gaitsgde/grad_2009/SeminarNotes/Nov17-19(Crystals).pdf Here's an encouragingly short set of notes on it].<br />
<br />
* What and why is a dessin d'enfants?<br />
<br />
* DG Schemes.<br />
<br />
<br />
==Ed Dewey's Wish List Of Olde==<br />
<br />
Back in the day Ed and Nathan made this list of topics they wanted to hear. They all sound super duper cool, but it's also true that they had many years of AG behind their backs, so this list might not be very representative of what the GAGS audience wants to hear bout.<br />
<br />
Here are the topics we're '''DYING''' to learn about! Please consider looking into one of these topics and giving one or two GAGS talks.<br />
<br />
===Specifically Vague Topics===<br />
* D-modules 101: basics of D-modules, equivalence between left and right D-modules, pullbacks, pushforwards, maybe the Gauss-Manin Connection. Claude Sabbah's introduction to the subject could be a good place to start.<br />
<br />
* Sheaf operations on D-modules (the point is that then you can get a Fourier-Mukai transform between certain O-modules and certain D-modules, which is more or less how geometric Langlands is supposed to work)<br />
<br />
===Famous Theorems===<br />
<br />
===Interesting Papers & Books===<br />
* ''Symplectic structure of the moduli space of sheaves on an abelian or K3 surface'' - Shigeru Mukai.<br />
<br />
* ''Residues and Duality'' - Robin Hatshorne.<br />
** Have you heard of Serre Duality? Would you like to really understand the nuts and bolts of it and its generalizations? If so this book is for you. (You wouldn't need to read the whole book to give a talk ;).)<br />
<br />
* ''Coherent sheaves on P^n and problems in linear algebra'' - A. A. Beilinson.<br />
** In this two page paper constructs the semi-orthogonal decomposition of the derived category of coherent sheaves on projective space. (This topic is very important, and there are a ton of other resources for this result and the general theory of derived categories.)<br />
<br />
* ''Frobenius splitting and cohomology vanishing for Schubert varieties'' - V.B. Mehta and A. Ramanathan.<br />
** In characteristic p the fact that (x+y)^p=x^p+y^p means that one has the Frobenius morphism, which sends f to f^p. In this paper the authors introduce the notion of what it means for a variety to be Frobenius split, and use this to prove certain cohomologcal vanishing results for Schubert varieties. Since then Frobenius splitting -- and its related cousins (F-regularity, strong F-regularity, F-purity, etc.) have played large roles in geometry and algebra in characteristic p. This is a good place to get a sense for what kicked all this stuff off! <br />
<br />
* ''Schubert Calculus'' - S. L. Kleiman and Dan Laksov.<br />
** An introduction to Schubert calculus suitable for those of all ages. I am told the paper essentially only uses linear algebra!<br />
<br />
* ''Rational Isogenies of Prime Degree'' - Barry Mazur.<br />
** In this paper Mazur classifies all isogenies of rational elliptic curves of prime order. As a result of this he deduces his famous result that the torsion subgroup of an elliptic curve (over Q) is one of 15 abelian groups. This definitely stares into the land of number theory, but certainly would still be of interest to many.<br />
<br />
* ''Esquisse d’une programme'' - Alexander Grothendieck.<br />
** Originating from a grant proposal in the mid 1980's this famous paper outlines a tantalizing research program, which seeks to tie numerous different areas of math (algebraic geometry, Teichmuller theory, Galois theory, etc.) together. This is where Grothendieck introduced his famous Lego game and dessin d'enfant. While just a research proposal this paper has seemingly inspired a ton of cool math, and will allow you to "blow peoples’ minds". (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Géométrie algébraique et géométrie analytique'' - J.P. Serre.<br />
** A projective variety X over the complex numbers has two lives, an algebraic and an analytic, depending on which topology one wishes to work with. That is one can think about X as a complex manifold and work with holomorphic functions or as an algebraic variety and work with regular functions. Hence to any complex projective variety we have two sheaf theories and as a result two cohomology theories. In this famous paper Serre compares these two and shows they are in fact the same. (''Note: This is a super fundamental result that is used all the time; normally in the following way: Uhh... What do you mean by cohomology? Well by GAGA or something it doesn't really mater.) (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Limit linear series: Basic theory''- David Eisenbud and Joe Harris.<br />
** One of the more profitable tools -- especially when studying moduli spaces -- in a geometers tool box is the theory of degenerations. However, sometimes we care about more than just the variety we are degenerating and want to keep track of things like vector/line bundles. In this paper Eisenbud and Harris develop the theory of degenerating a curve together with a linear series. From this they prove a ton of cool results: M_g is of general type for g>24, Brill-Noether theory, etc.<br />
<br />
* ''Picard Groups of Moduli Problems'' - David Mumford.<br />
** This paper is essentially the origin of algebraic stacks.<br />
<br />
* ''The Structure of Algebraic Threefolds: An Introduction to Mori's Program'' - Janos Kollar<br />
** This paper is an introduction to Mori's famous ``minimal model'' program, which is a far reaching program seeking to understand the birational geometry of higher dimensional varieties. <br />
<br />
* ''Cayley-Bacharach Formulas'' - Qingchun Ren, Jürgen Richter-Gebert, Bernd Sturmfels.<br />
** A classical result we all learn in a first semester of algebraic geometry is that 5 points in the plane (in general position) determine a unique plane conic. One can similarly show that 9 (general) points in the plane determine a unique plane cubic curve. This paper tries to answer the question: ``What is equation for this cubic curve?''.<br />
<br />
* ''On Varieties of Minimal Degree (A Centennial Approach)'' - David Eisenbud and Joe Harris.<br />
** Suppose X is a projective variety embedded in projective space so that X is not contained in any hyperplane. By projecting from general points one can see that the degree of X is at least codim(X)+1. This paper discusses the classification of varieties that achieve this lower degree bound i.e. varieties of minimal degree. This topic is quite classical and the paper seems to contain a nice mixture of classical and modern geometry.<br />
<br />
* ''The Gromov-Witten potential associated to a TCFT'' - Kevin J. Costello.<br />
** This seems incredibly interesting, but fairing warning this paper has been described as ''highly technical'', which considering it uses A-infinity algebras and the derived category of a Calabi-Yau seems like a reasonable description. (This paper may be covered in Caldararu's Spring 2017 topics course.)<br />
__NOTOC__<br />
<br />
== Fall 2019 ==<br />
<br />
<center><br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#A6B658" width="300" align="center"|'''Speaker'''<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title (click to see abstract)'''<br />
|-<br />
| bgcolor="#E0E0E0"| September 18<br />
| bgcolor="#C6D46E"| David Wagner<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#September 18| M_g Potpourri]]<br />
|-<br />
| bgcolor="#E0E0E0"| September 25<br />
| bgcolor="#C6D46E"| Shengyuan Huang<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#September 25| Derived Groups and Groupoids]]<br />
|-<br />
| bgcolor="#E0E0E0"| October 9<br />
| bgcolor="#C6D46E"| Brandon Boggess<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 9| Geometry of Generalized Fermat Curves ]]<br />
|-<br />
| bgcolor="#E0E0E0"| October 16<br />
| bgcolor="#C6D46E"| Soumya Sankar<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 16| Brauer groups and obstruction problems]]<br />
|-<br />
| bgcolor="#E0E0E0"| October 23<br />
| bgcolor="#C6D46E"| Alex Mine<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 23| The Ax-Grothendieck theorem and other fun stuff]]<br />
|-<br />
| bgcolor="#E0E0E0"| October 30<br />
| bgcolor="#C6D46E"| Vlad Sotirov<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 30| Buildings and algebraic groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| November 6<br />
| bgcolor="#C6D46E"| Connor Simpson<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 6| Lorentzian Polynomials]]<br />
|-<br />
| bgcolor="#E0E0E0"| November 13<br />
| bgcolor="#C6D46E"| Alex Hof<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 13| Tropicalization Blues]]<br />
|-<br />
| bgcolor="#E0E0E0"| November 20<br />
| bgcolor="#C6D46E"| Caitlyn Booms<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 20| Computing Gr<span>&#246;</span>bner Bases of Submodules]]<br />
|-<br />
| bgcolor="#E0E0E0"| November 27<br />
| bgcolor="#C6D46E"| Thanksgiving Break<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 27| ]]<br />
|-<br />
| bgcolor="#E0E0E0"| December 4<br />
| bgcolor="#C6D46E"| Colin Crowley<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#December 4| Hyperplane arrangements and maximum likelihood degree]]<br />
|-<br />
| bgcolor="#E0E0E0"| December 11<br />
| bgcolor="#C6D46E"| Erika Pirnes<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#December 11| The Buchsbaum-Eisenbud-Horrocks Conjecture]]<br />
|}<br />
</center><br />
<br />
== September 18 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''David Wagner'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: M_g Potpourri<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: In 1983, David Mumford proposed that the rational cohomology ring of Mg should be a polynomial algebra. I will discuss some of the history of Mumford's conjecture, possibly indicating a few ideas from the 2007 proof as the Madsen-Weiss theorem. If all goes well, the talk will take us through such diverse places as homotopy theory, representation stability, combinatorics of ribbon graph complexes, and deformations of algebras.<br />
<br />
|} <br />
</center><br />
<br />
== September 25 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Shengyuan Huang'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Derived Groups and Groupoids<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: In this talk, we will discuss groups and groupoids in the derived category of dg schemes. I will focus on examples instead of the abstract theory. If X is a smooth subscheme of a smooth scheme S over the field of complex numbers, then the derived self-intersection of X in S is a groupoid. We will investigate the corresponding Lie algebroid of the groupoid I mentioned above, and exponential map between them.<br />
<br />
|} <br />
</center><br />
<br />
== October 9 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Brandon Boggess'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Geometry of Generalized Fermat Curves <br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: We will look at the generalized Fermat equation, and see how studying its integral points leads one to study quotient stacks. We will then very quickly turn and run away from the general picture to a particularly simple example of these quotient stacks, the M-curves of Darmon-Granville, and how they can be used to say something about integral points without having to actually know what the hell a stack is.<br />
|} <br />
</center><br />
<br />
== October 16 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Soumya Sankar'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Brauer groups and obstruction problems<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: Brauer groups are ubiquitous in arithmetic and algebraic geometry. I will try to describe different contexts in which they appear, ranging from Brauer groups of fields and class field theory, to obstructions to moduli problems and derived equivalences. <br />
|} <br />
</center><br />
<br />
== October 23 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Alex Mine'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: The Ax-Grothendieck theorem and other fun stuff<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: The Ax-Grothendieck theorem says that any polynomial map from C^n to C^n that is injective is also surjective. The way this is proven is to note that the statement is trivial over finite fields, and somehow use this to work up to the complex numbers. We'll talk about this and other ways of translating information between finite fields and C.<br />
<br />
|} <br />
</center><br />
<br />
== October 30 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Vlad Sotirov'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Buildings and algebraic groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: I will give a concrete introduction to the notion of a Tits building and its relationship to algebraic groups.<br />
<br />
|} <br />
</center><br />
<br />
== November 6 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Connor Simpson'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Lorentzian Polynomials<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract:<br />
Lorentzian polynomials are a family of multivariate polynomials recently introduced by Branden and Huh. We will define Lorentzian polynomials and survey some of their applications to combinatorics, representation theory, and computer science. The first 20 minutes of this talk should not require more than the ability to take partial derivatives of polynomials and basic linear algebra.<br />
|} <br />
</center><br />
<br />
== November 13 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Alex Hof'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Tropicalization Blues<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: Tropicalization turns algebro-geometric objects into piecewise linear ones which can then be studied through the lens of combinatorics. In this talk, I will introduce the basic construction, then discuss some of the recent efforts to generalize and improve upon it, touching upon the Giansiracusa tropicalization and <s>developing</s> gazing wistfully in the direction of the machinery of ordered blueprints necessary for the Lorscheid tropicalization.<br />
<br />
|} <br />
</center><br />
<br />
== November 20 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Caitlyn Booms'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Computing Gr<span>&#246;</span>bner Bases of Submodules<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: In this talk, we will give motivation for and define Gr<span>&#246;</span>bner bases of submodules of finitely generated free modules over a polynomial ring S=k[x_1,...,x_r]. Not only are such bases extremely useful in constructive module theory and elimination theory, they are actually computable thanks to Buchberger's Algorithm. Further, they have a wide variety of applications in algebraic geometry including aiding in the computation of syzygies (kernels of maps of finitely generated, free S-modules), Hilbert functions, intersections of submodules, saturations, annihilators, projective closures, and elimination ideals. We will work through several examples and discuss some of these applications.<br />
<br />
|} <br />
</center><br />
<br />
== November 28 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Thanksgiving Break'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title:<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
|} <br />
</center><br />
<br />
== December 4 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Colin Crowley'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Hyperplane arrangements and maximum likelihood degree<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: The topology of the complements of hyperplane arrangements encode lots of interesting combinatorial information about the arrangements. I’ll state (and hopefully mostly prove) a neat fact about the Euler characteristic of the complement of a complex (essential) hyperplane arrangement, and discuss how it has recently been generalized to a larger class of varieties.<br />
<br />
|} <br />
</center><br />
<br />
== December 11 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Erika Pirnes'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: The Buchsbaum-Eisenbud-Horrocks Conjecture<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: Betti numbers are defined to be the ranks of the free modules in the free resolution of a module. The Buchsbaum-Eisenbud-Horrocks conjecture gives upper bounds for the Betti numbers. I'll state the conjecture and give some examples.<br />
<br />
|} <br />
</center><br />
<br />
== Organizers' Contact Info ==<br />
<br />
<br />
[https://sites.google.com/wisc.edu/cbooms/ Caitlyn Booms]<br />
<br />
[http://www.math.wisc.edu/~drwagner/ David Wagner]<br />
<br />
<br />
== Past Semesters ==<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2019 Spring 2019]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2018 Fall 2018]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2018 Spring 2018]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2017 Fall 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2017 Spring 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2016 Fall 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2016 Spring 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_(Fall_2015) Fall 2015]</div>Drwagnerhttps://www.math.wisc.edu/wiki/index.php/NTS_Fall_Semester_2019NTS Fall Semester 20192020-01-16T19:01:47Z<p>Shi: </p>
<hr />
<div>= Number Theory / Representation Theory Seminar, University of Wisconsin - Madison =<br />
<br />
<br />
*'''When:''' Thursdays, 2:30 PM – 3:30 PM<br />
*'''Where:''' Van Vleck B321<br />
*Please join the [https://mailhost.math.wisc.edu/mailman/listinfo/nts NT/RT mailing list:] (you must be on a math department computer to use this link).<br />
<br />
There is also an accompanying [https://www.math.wisc.edu/wiki/index.php/NTSGrad_Fall_2019 graduate-level seminar], which meets on Tuesdays.<br><br />
<br />
You can find our Spring 2020 speakers in [https://www.math.wisc.edu/wiki/index.php/NTS_Spring_Semester_2020 Spring 2020]. <br />
<br><br />
You can find our Spring 2019 speakers in [https://www.math.wisc.edu/wiki/index.php/NTS_Spring_Semester_2019 Spring 2019]. <br />
<br><br />
You can find our previous speakers in [https://www.math.wisc.edu/wiki/index.php/NTS_Fall_2018_Semester Fall 2018].<br />
<br />
= Fall 2019 Semester =<br />
<center><br />
<br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#F0A0A0" width="300" align="center"|'''Speaker''' (click for homepage)<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title''' (click for abstract)<br />
|- <br />
| bgcolor="#E0E0E0" align="center" | Sep 5<br />
| bgcolor="#F0B0B0" align="center" | Will Sawin (Columbia)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Sep_5 The sup-norm problem for automorphic forms over function fields and geometry]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Sep 12<br />
| bgcolor="#F0B0B0" align="center" | Yingkun Li (Darmstadt)<br />
| bgcolor="#BCE2FE"|[https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Sep_12 CM values of modular functions and factorization]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Sep 19<br />
| bgcolor="#F0B0B0" align="center" | Soumya Sankar (Madison)<br />
| bgcolor="#BCE2FE"|[https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Sep_19 Proportion of ordinary curves in some families]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Sep 26<br />
| bgcolor="#F0B0B0" align="center" | [https://www.math.wisc.edu/wiki/index.php/Colloquia Special Colloquium Lecture]<br />
| bgcolor="#BCE2FE"|<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Oct 3<br />
| bgcolor="#F0B0B0" align="center" | Patrick Allen (UIUC)<br />
| bgcolor="#BCE2FE"|[https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Oct_3 On the modularity of elliptic curves over imaginary quadratic fields]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Oct 10<br />
| bgcolor="#F0B0B0" align="center" | Borys Kadets (MIT)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Oct_10 Sectional monodromy groups of projective curves]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Oct 17<br />
| bgcolor="#F0B0B0" align="center" | Yousheng Shi (Madison)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Oct_17 Generalized special cycles and theta series]<br />
|- <br />
| bgcolor="#E0E0E0" align="center" | Oct 24<br />
| bgcolor="#F0B0B0" align="center" | Simon Marshall (Madison)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Oct_24 Counting cohomological automorphic forms on $GL_3$ ]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Nov 7<br />
| bgcolor="#F0B0B0" align="center" | Asif Zaman (Toronto)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Nov_7 A zero density estimate for Dedekind zeta functions ] <br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Nov 14<br />
| bgcolor="#F0B0B0" align="center" | Liyang Yang (Caltech)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Nov_14 Holomorphic Continuation of Certain $L$-functions via Trace Formula] <br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Nov 21<br />
| bgcolor="#F0B0B0" align="center" | Tony Feng (MIT)<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Nov_21 Steenrod operations and the Artin-Tate pairing]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Nov 26 (Note different day)<br />
| bgcolor="#F0B0B0" align="center" | Brandon Alberts<br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Nov_26 Counting Towers of Number Fields]<br />
|-<br />
| bgcolor="#E0E0E0" align="center" | Dec 5<br />
| bgcolor="#F0B0B0" align="center" | Benjamin Breen <br />
| bgcolor="#BCE2FE"| [https://www.math.wisc.edu/wiki/index.php/NTS_ABSTRACTFall2019#Dec_05 Unit signatures and narrow class groups of odd abelian number fields]<br />
|-<br />
<br />
<br />
<br />
<br />
|}<br />
</center><br />
<br />
<br><br />
<br />
*to be confirmed</div>Shihttps://www.math.wisc.edu/wiki/index.php/Past_Probability_Seminars_Fall_2019Past Probability Seminars Fall 20192020-01-09T15:26:36Z<p>Valko: Created page with " Back to Current Probability Seminar Schedule Back to Past Seminars = Fall 2019 = <b>Thursdays in 901 Van Vleck Hall at 2:30..."</p>
<hr />
<div>[[Probability Seminar | Back to Current Probability Seminar Schedule ]]<br />
<br />
<br />
[[Past Seminars | Back to Past Seminars]]<br />
<br />
<br />
= Fall 2019 =<br />
<br />
<b>Thursdays in 901 Van Vleck Hall at 2:30 PM</b>, unless otherwise noted. <br />
<b>We usually end for questions at 3:20 PM.</b><br />
<br />
If you would like to sign up for the email list to receive seminar announcements then please send an email to <br />
[mailto:join-probsem@lists.wisc.edu join-probsem@lists.wisc.edu]<br />
<br />
<br />
== September 12, 2019, [https://perso.univ-rennes1.fr/victor.kleptsyn/ Victor Kleptsyn], CNRS and University of Rennes 1 ==<br />
'''Furstenberg theorem: now with a parameter!'''<br />
<br />
The classical Furstenberg theorem describes the (almost sure) behaviour of a random product of independent matrices; their norms turn out to grow exponentially. In our joint work with A. Gorodetski, we study what happens if the random matrices depend on an additional parameter. <br />
It turns out that in this new situation, the conclusion changes. Namely, under some conditions, there almost surely exists a (random) "exceptional" set on parameters where the lower limit for the Lyapunov exponent vanishes.<br />
Our results are related to the Anderson localization in dimension one, providing a purely dynamical viewpoint on its proof. I will also speak about some generalizations and related open questions.<br />
<br />
== September 19, 2019, [http://math.columbia.edu/~xuanw Xuan Wu], Columbia University==<br />
<br />
'''A Gibbs resampling method for discrete log-gamma line ensemble.'''<br />
<br />
In this talk we will construct the discrete log-gamma line ensemble, which is assocaited with inverse gamma polymer model. This log-gamma line ensemble enjoys a random walk Gibbs resampling invariance that follows from the integrable nature of the inverse gamma polymer model via geometric RSK correspondance. By exploiting such resampling invariance, we show the tightness of this log-gamma line ensemble under weak noise scaling. Furthermore, a Gibbs property, as enjoyed by KPZ line ensemble, holds for all subsequential limits.<br />
<br />
== October 10, 2019, NO SEMINAR - [https://sites.math.northwestern.edu/mwp/ Midwest Probability Colloquium] ==<br />
<br />
== October 17, 2019, [https://www.usna.edu/Users/math/hottovy/index.php Scott Hottovy], USNA ==<br />
<br />
''' Simplified dynamics for noisy systems with delays.'''<br />
<br />
Many biological and physical systems include some type of random noise with a temporal delay. For example, many sperm cells travel in a random motion where their velocity changes according to a chemical signal. This chemotaxis is transmitted through a delay in the system. That is, the sperm notices chemical gradients after a certain time has elapsed. In this case, the delay causes the sperm to aggregate around the egg. In this talk I will consider a general stochastic differential delay equation (SDDE) with state-dependent colored noises and derive its limit as the time delays and the correlation times of the noises go to zero. The analysis leads to a much simpler Stochastic Differential Equation to study. The work is motivated by an experiment involving an electrical circuit with noisy, delayed feedback. The main methods used in the proof are a theorem about convergence of solutions of stochastic differential equations by Kurtz and Protter and a maximal inequality for sums of a stationary sequence of random variables by Peligrad and Utev.<br />
<br />
== October 24, 2019, [https://math.temple.edu/~brider/ Brian Rider], Temple University ==<br />
<br />
'''A general beta crossover ensemble'''<br />
<br />
I'll describe an operator limit for a family of general beta ensembles which exhibit a double-scaling. In particular, a free parameter in the system provides for a crossover between the more well-known "soft" and "hard" edge point processes. This new limit operator takes as input the Riccati diffusion associated with the Stochastic Airy Operator. I like to suggest that this hints at a hierarchy of random operators analogous to the Painlevé hierarchy observed at the level of correlation functions for double-scaling ensembles most widely studied at beta = 2. Full disclosure: the result remains partially conjectural due to an unresolved uniqueness question, but I’ll provide lots of evidence to convince you we have the right answer. Joint work with Jose Ramírez (Univ. Costa Rica).<br />
<br />
== October 31, 2019, Vadim Gorin, UW Madison==<br />
<br />
'''Shift invariance for the six-vertex model and directed polymers.'''<br />
<br />
I will explain a recently discovered mysterious property in a variety of stochastic systems ranging from the six-vertex model and to the directed polymers, last passage percolation, Kardar-Parisi-Zhang equation, and Airy sheet. Vaguely speaking, the property says that the multi-point joint distributions are unchanged when some (but not necessarily all!) points of observations are shifted. The property leads to explicit computations for the previously inaccessible joint distributions in all these settings.<br />
<br />
== November 7, 2019, [https://people.kth.se/~tobergg/ Tomas Berggren], KTH Stockholm ==<br />
'''Domino tilings of the Aztec diamond with doubly periodic weightings'''<br />
<br />
This talk will be centered around domino tilings of the Aztec diamond with doubly periodic weightings. In particular asymptotic results of the $ 2 \times k $-periodic Aztec diamond will be discussed, both in the macroscopic and microscopic scale. The macroscopic picture is described using a close connection to a Riemann surface. For instance, the number of smooth regions (also called gas regions) is the same as the genus of the mentioned Riemann surface. <br />
<br />
The starting point of the asymptotic analysis is a non-intersecting path formulation and a double integral formula for the correlation kernel. The proof of this double integral formula is based on joint work with M. Duits, which will be discuss briefly if time permits.<br />
<br />
== November 14, 2019, [https://math.mit.edu/directory/profile.php?pid=2076 Benjamin Landon], MIT ==<br />
'''Universality of extremal eigenvalue statistics of random matrices'''<br />
<br />
The past decade has seen significant progress on the understanding of universality of various eigenvalue statistics of random matrix theory. However, the behavior of certain ``extremal'' or ``critical'' observables is not fully understood. Towards the former, we discuss progress on the universality of the largest gap between consecutive eigenvalues. With regards to the latter, we discuss the central limit theorem for the eigenvalue counting function, which can be viewed as a linear spectral statistic with critical regularity and has logarithmically growing variance.<br />
<br />
== November 21, 2019, Tung Nguyen, UW Madison ==<br />
<br />
'''Prevalence of deficiency zero reaction networks under an Erdos-Renyi framework<br />
'''<br />
<br />
Reaction network models, which are used to model many types of systems in biology, have grown dramatically in popularity over the past decade. This popularity has translated into a number of mathematical results that relate the topological features of the network to different qualitative behaviors of the associated dynamical system. One of the main topological features studied in the field is ''deficiency'' of a network. A reaction network which has strong connectivity in its connected components and a deficiency of zero is stable in both the deterministic and stochastic dynamical models.<br />
<br />
This leads to the question: how prevalent are deficiency zero models among all such network models. In this talk, I will quantify the prevalence of deficiency zero networks among random reaction networks generated under an Erdos-Renyi framework. Specifically, with n being the number of species, I will uncover a threshold function r(n) such that the probability of the random network being deficiency zero converges to 1 if the edge probability p_n << r(n) and converges to 0 if p_n >> r(n).</div>Valkohttps://www.math.wisc.edu/wiki/index.php/NTSGrad_Spring_2020NTSGrad Spring 20202020-01-02T04:19:25Z<p>Soumyasankar: </p>
<hr />
<div>= Graduate Student Number Theory / Representation Theory Seminar, University of Wisconsin – Madison =<br />
<br />
*'''When:''' Tuesdays, 2:30 PM – 3:30 PM<br />
*'''Where:''' B321 Van Vleck<br />
<br />
The purpose of this seminar is to have a talk on each Tuesday by a graduate student to<br />
help orient ourselves for the [[NTS| Number Theory Seminar]] talk on the following Thursday.<br />
These talks are generally aimed at beginning graduate students, and try to <br />
explain some of the background, terminology, and ideas for the Thursday talk.<br />
<br />
This semester, we will be watching lectures of the [https://sites.google.com/view/vantageseminar| VaNTAGe Seminar], every other Tuesday (starting January 21st). VaNTAGe is an online seminar on open conjectures in Number Theory. The schedule can be found on the website. The watch-party will be held in 901 VV at Noon. <br />
<br />
= Spring 2020 Semester: Schedule =<br />
<br />
<center><br />
<br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#F0A0A0" width="300" align="center"|'''Speaker''' (click for homepage)<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title''' (click for abstract)<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Jan 21st<br />
| bgcolor="#F0A0A0" width="300" align="center"| Qiao He<br />
| bgcolor="#BCD2EE" width="300" align="center"| [[NTSGrad_Spring 2020/Abstracts#Jan_21|Representation theory and arithmetic geometry]]<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Jan 28th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Feb 4th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Feb 11th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Feb 18th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Feb 25th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Mar 3rd<br />
| bgcolor="#F0A0A0" width="300" align="center"|Arizona Winter School Week<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Mar 10th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Mar 17th<br />
| bgcolor="#F0A0A0" width="300" align="center"|Spring Break<br />
| bgcolor="#BCD2EE" width="300" align="center"|No talk<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Mar 24th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Mar 31st<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Apr 7th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Apr 14th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Apr 21st<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|Apr 28th<br />
| bgcolor="#F0A0A0" width="300" align="center"|<br />
| bgcolor="#BCD2EE" width="300" align="center"|<br />
|-<br />
<br />
|}<br />
<br />
</center><br />
<br />
<br><br />
<br />
= Organizer(s) =<br />
<br />
Brandon Boggess (bboggess@math.wisc.edu)<br />
<br />
Soumya Sankar (ssankar3@wisc.edu)<br />
<br />
<br />
== Former Organizers ==<br />
<br />
Brandon Alberts <br />
<br />
Megan Maguire <br />
<br />
Ryan Julian<br />
<br />
= Other Graduate NTS Pages =<br />
<br />
The seminar webpage for Spring 2019 is [[NTSGrad_Spring_2019|here]].<br><br />
The seminar webpage for Fall 2018 is [[NTSGrad_Fall_2018|here]].<br><br />
The seminar webpage for Spring 2018 is [[NTSGrad_Spring_2018|here]].<br><br />
The seminar webpage for Fall 2017 is [[NTSGrad|here]].<br><br />
The seminar webpage for Spring 2017 is [[NTSGrad_Spring_2017|here]].<br><br />
The seminar webpage for Fall 2016 is [[NTSGrad_Fall_2016|here]]<br><br />
The seminar webpage for Spring 2016 is [[NTSGrad_Spring_2016|here]]<br><br />
The seminar webpage for Fall 2015, is [[NTSGrad_Fall_2015|here]].<br><br />
<br />
----<br />
Return to the [[NTS|Number Theory Seminar Page]]<br />
<br />
Return to the [[Algebra|Algebra Group Page]]</div>Soumyasankarhttps://www.math.wisc.edu/wiki/index.php/How_to_Use_Intel_Parallel_Studio_Compilers_(icc_and_ifort)How to Use Intel Parallel Studio Compilers (icc and ifort)2019-12-11T20:05:10Z<p>Jheim: </p>
<hr />
<div>The Math Department supports the Intel C++ compiler, icc, and the Intel FORTRAN compiler, ifort. These programs should be available on all department desktop workstations and research machines.<br />
<br />
To use these compilers, do the following:<br />
<br />
# Open a terminal window. Math department workstations have several terminal emulators installed. The default emulator can be opened using Control+Alt+t.<br />
# Source a script to set the proper environmental variables for your choice of compiler (see below).<br />
# Use either icc or ifort to compile your code. Example, "icc -o HelloWorld helloworld.c"<br />
<br />
Tip: The Math Department IT staff strongly suggests you consider using the "make" utility to compile your code. Google "makefile" for more information.<br />
<br />
== Sourcing a Script To Set Environmental Variables ==<br />
<br />
Before you can use the Intel compilers, you must source a shell script to set environmental variables. If you see an error message that says the compiler was unable to check out a license, that is probably because you did not source the appropriate script. You will have to choose a script based upon your choice of login shell and compiler. <br />
<br />
Most users at the Math Department are using bash as their shell. The alternative is tcsh. You can determine which shell you are using by typing, "echo $SHELL" at a command prompt.<br />
<br />
The scripts also require you to specify a choice of architecture for the compiler. The choices are ia32 or intel64. You will probably wish to compile your code for the intel64 architecture. While ia32 provides greater portability, the Math Department no longer has any 32-bit machines. Your code will run faster on a 64-bit machine if compiled for the intel64 architecture.<br />
<br />
To set environmental variables in the bash shell for the Intel C++ compiler:<br />
* source /usr/local/intel/iccvars.sh intel64<br />
<br />
For the bash shell and the Intel FORTRAN compiler:<br />
* source /usr/local/intel/ifortvars.sh intel64<br />
<br />
To set environmental variables in the tcsh shell for the Intel C++ compiler:<br />
* source /usr/local/intel/iccvars.csh intel64<br />
<br />
For the tcsh shell and the Intel FORTRAN compiler:<br />
* source /usr/local/intel/ifortvars.csh intel64<br />
<br />
Tip: To avoid having to type these commands each time you log into a department workstation or research machine, we suggest you add these commands to the start up script for your shell. For bash, that is .bashrc and for tcsh it is .login.</div>Jheimhttps://www.math.wisc.edu/wiki/index.php/How_to_connect_to_our_servers_from_outside_of_Van_VleckHow to connect to our servers from outside of Van Vleck2019-12-11T18:31:10Z<p>Jheim: Using ssh</p>
<hr />
<div> <br />
Editing Using ssh (section)<br />
= Using ssh to Access Math Department Resources=<br />
<br />
The University of Wisconsin-Madison Department of Mathematics maintains two login servers for ssh connections from outside the department.<br />
<br />
# login0.math.wisc.edu: To connect to this server, you must have an IP address that corresponds to a wisc.edu host address. You can use the campus wireless[https://it.wisc.edu/services/wireless-uwnet/ | UWNet], [https://it.wisc.edu/services/wireless-eduroam/ | Eduroam], or [https://it.wisc.edu/services/wiscvpn/ | WiscVPN]. Other names for this server are bing.math.wisc.edu and login.math.wisc.edu.<br />
# login1.math.wisc.edu. To connect to this server, you must use an ssh key. For instructions on using an ssh key, see below. Another name for this server is abel.math.wisc.edu.<br />
<br />
To access Math Department resources via ssh, you must first use an ssh client to connect to either login0 or login1. You can then ssh to the system of your choice within the department.<br />
<br />
For example, suppose you wished to run a sage program on one of the research servers. For simplicity sake, the research servers have aliases (nicknames) magma0, magma1, ..., magma19, with the more powerful machines having the lowest numbers.<br />
<br />
To start your sage program, you might use an ssh client on your laptop to connect to login0.math.wisc.edu then run ssh again on login0 to connect to magma0. Please do not run research programs on login0 or login1. While these machines may have all the tools necessary to test programs, they are not powerful enough to handle more than the most trivial of tasks. If you run a program that uses a lot of resources on login0 or login1, you may prevent users (including yourself) from accessing these machines.<br />
===Generating an ssh Key===<br />
<br />
The IT staff recommends that you generate an ssh key to use when moving from one machine to another within the department network. Using an ssh key is both easier and more secure than retyping your password when you are moving from one Math Department machine to another. To use an ssh key, do the following.<br />
<br />
# Log onto any Linux workstation or research server in the department. You can use ssh as explained above to connect to login0 or login1 for this purpose.<br />
# At the prompt, type "ssh-keygen". Accept the default values. You need not enter a passphrase, so just press enter.<br />
# Add the key you just generated to your authorized_keys file. Type, "cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys"<br />
# To test, type, "ssh magma0". You should be connected to magma0 without having to retype your password.<br />
<br />
Note: The login server login1.math.wisc.edu requires the use of ssh keys to connect. You can use this same ssh key for that purpose. Instructions for doing so are different for each ssh client and are therefore beyond the scope of this document. Consult your client's documentation (or google) or ask a member of the IT staff for assistance.<br />
Summary:<br />
203<br />
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Powered by MediaWiki</div>Jheimhttps://www.math.wisc.edu/wiki/index.php/Using_sshUsing ssh2019-11-15T21:25:06Z<p>Jheim: /* Using ssh to Access Math Department Resources */</p>
<hr />
<div>= Using ssh to Access Math Department Resources=<br />
<br />
The University of Wisconsin-Madison Department of Mathematics maintains two login servers for ssh connections from outside the department.<br />
<br />
# login0.math.wisc.edu: To connect to this server, you must have an IP address that corresponds to a wisc.edu host address. You can use the campus wireless[https://it.wisc.edu/services/wireless-uwnet/ | UWNet], [https://it.wisc.edu/services/wireless-eduroam/ | Eduroam], or [https://it.wisc.edu/services/wiscvpn/ | WiscVPN]. Other names for this server are bing.math.wisc.edu and login.math.wisc.edu.<br />
# login1.math.wisc.edu. To connect to this server, you must use an ssh key. For instructions on using an ssh key, see below. Another name for this server is abel.math.wisc.edu.<br />
<br />
To access Math Department resources via ssh, you must first use an ssh client to connect to either login0 or login1. You can then ssh to the system of your choice within the department.<br />
<br />
For example, suppose you wished to run a sage program on one of the research servers. For simplicity sake, the research servers have aliases (nicknames) magma0, magma1, ..., magma19, with the more powerful machines having the lowest numbers.<br />
<br />
To start your sage program, you might use an ssh client on your laptop to connect to login0.math.wisc.edu then run ssh again on login0 to connect to magma0. Please do not run research programs on login0 or login1. While these machines may have all the tools necessary to test programs, they are not powerful enough to handle more than the most trivial of tasks. If you run a program that uses a lot of resources on login0 or login1, you may prevent users (including yourself) from accessing these machines.<br />
===Generating an ssh Key===<br />
<br />
The IT staff recommends that you generate an ssh key to use when moving from one machine to another within the department network. Using an ssh key is both easier and more secure than retyping your password when you are moving from one Math Department machine to another. To use an ssh key, do the following.<br />
<br />
# Log onto any Linux workstation or research server in the department. You can use ssh as explained above to connect to login0 or login1 for this purpose.<br />
# At the prompt, type "ssh-keygen". Accept the default values. You need not enter a passphrase, so just press enter.<br />
# Add the key you just generated to your authorized_keys file. Type, "cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys"<br />
# To test, type, "ssh magma0". You should be connected to magma0 without having to retype your password.<br />
<br />
Note: The login server login1.math.wisc.edu requires the use of ssh keys to connect. You can use this same ssh key for that purpose. Instructions for doing so are different for each ssh client and are therefore beyond the scope of this document. Consult your client's documentation (or google) or ask a member of the IT staff for assistance.</div>Jheimhttps://www.math.wisc.edu/wiki/index.php/Colloquia/Fall_2020Colloquia/Fall 20202019-11-06T03:00:57Z<p>Qinli: </p>
<hr />
<div>{| cellpadding="8"<br />
!align="left" | date <br />
!align="left" | speaker<br />
!align="left" | title<br />
!align="left" | host(s)<br />
|-<br />
|Sept 18<br />
| [https://users.oden.utexas.edu/~pgm/ Per-Gunnar Martinsson] (UT-Austin)<br />
| [[#Per-Gunnar Martinsson (UT-Austin) | TBA ]]<br />
| Li<br />
|-<br />
|Sept 25<br />
| [webpage name] (institute)<br />
|[[#name (institute)| Title ]]<br />
| host</div>Qinlihttps://www.math.wisc.edu/wiki/index.php/SIAM_Student_Chapter_Seminar/Spring2017SIAM Student Chapter Seminar/Spring20172019-11-04T15:42:48Z<p>Jeanluc: Create page from old website.</p>
<hr />
<div>= Spring 2017<br />
<br />
Date Speaker Title<br />
<br />
March 17 Polly Yu Zeeman deceleration: motivation, simulation and experiment<br />
<br />
March 31 Alisha Zachariah Low Complexity (RADAR) Channel Estimation<br />
<br />
April 14 Jim Brunner Robust permanence of polynomial dynamical systems<br />
<br />
April 28 Zachary Charles Subspace clustering with missing data<br />
<br />
<br />
<br />
<br />
<br />
<br />
Abstracts (2017 Spring)<br />
April 28: Zachary Charles<br />
Title: Subspace clustering with missing data<br />
<br />
Abstract: In many applications (recommender systems, GPS, medical records) we want to recover a matrix given from an incomplete sampling of its entries. Up to this point, work in this area has focused on the case that the underlying matrix is low rank. Unfortunately, this low-rank assumption is often not true in real-life settings. We instead consider the case when the columns of the matrix come from a union of low rank subspaces. This type of model has already been used to great effect in computer vision and image processing. We will show that by clustering the incomplete data points in to groups according to the subspace they come from, we can often recover the true matrix efficiently. This is ongoing work with Rebecca Willett and Amin Jalali.<br />
<br />
Note from the speaker: The talk will hopefully be of interest to anybody who enjoys optimization, machine learning, high-dimensional probability, or convex analysis. However, I will not assume background in any of those areas.<br />
<br />
April 14: Jim Brunner<br />
Title: Robust permanence of polynomial dynamical systems<br />
<br />
Abstract: A ``permanent" dynamical system is one whose positive solutions stay bounded away from zero and infinity. The permanence property has important applications in biochemistry, cell biology, and ecology. Inspired by reaction network theory, we define a class of polynomial dynamical systems called {\it tropically endotactic}. We show that these polynomial dynamical systems are permanent, irrespective to the values of (possibly time-dependent) parameters in these systems. These results generalize the permanence of 2D reversible and weakly reversible mass-action systems.<br />
<br />
Comment on the abstract (from Jim): While this talk sounds like a technical analysis talk, I want to emphasize that the interesting thing for the SIAM student chapter is not so much the result but instead the method of proof. I’ll introduce a thing called a “differential inclusion” and try to convince people that we can analyze ODE systems with polynomial right hand sides by turning our heads and squinting at them in the correct way.<br />
<br />
March 31: Alisha Zachariah<br />
Title: Low Complexity (RADAR) Channel Estimation<br />
<br />
Abstract: Several forms of wireless communication involve estimating the channel through which signals are sent. In this talk we will focus on the RADAR channel. My main motivation in this talk is to present an algebraic channel model that has a sophisticated underlying structure. I will present an existing algorithm that uses this and then develop a low complexity improvement that the structure suggests.<br />
<br />
March 17: Polly Yu<br />
Title: Zeeman deceleration: motivation, simulation and experiment<br />
<br />
Abstract: Granted there will be a lot of 'I don't know's, allow me to introduce the idea of cooling a particle beam by magnetic field. Specifically, I will talk about hydrogen atoms, and how to experimentally implement this cooling. Numerical simulation results will be presented along with pretty pictures. Some experimental data (for the non-decelerated beam) will also be presented; they don't look as pretty, but they remind us that experiments are hard, so patience needed when working with experimentalists.</div>Jeanluchttps://www.math.wisc.edu/wiki/index.php/SIAM_Student_Chapter_Seminar/Fall2018SIAM Student Chapter Seminar/Fall20182019-11-04T15:38:11Z<p>Jeanluc: Created page with "__NOTOC__ == Fall 2018 == {| cellpadding="8" !align="left" | date !align="left" | speaker !align="left" | title |- | Sept. 12 |[http://www.math.wisc.edu/~ke/ Ke Chen] (Math..."</p>
<hr />
<div>__NOTOC__<br />
<br />
== Fall 2018 ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
|-<br />
| Sept. 12<br />
|[http://www.math.wisc.edu/~ke/ Ke Chen] (Math)<br />
|''[[#Sep 12: Ke Chen (Math)|Inverse Problem in Optical Tomography]]''<br />
|-<br />
| Spet. 26 <br />
|[http://www.math.wisc.edu/~kehlert/ Kurt Ehlert] (Math)<br />
|''[[#Sept 26: Kurt Ehlert (Math)| How to bet when gambling]]''<br />
|-<br />
| Oct. 10 <br />
|[http://TBD Zachary Hansen] (Atmospheric and Oceanic Sciences)<br />
|''[[#Oct 10: Zachary Hansen (Atmospheric and Oceanic Sciences)| Land-Ocean contrast in lightning ]]''<br />
|-<br />
| Oct. 24 <br />
|[http://TBD Xuezhou Zhang] (Computer Science)<br />
|''[[#Oct 24: Xuezhou Zhang (Computer Science)| An Optimal Control Approach to Sequential Machine Teaching ]]''<br />
|-<br />
| Nov. 7 <br />
|[http://TBD Cancelled] <br />
|''[[#Nov 7: Cancelled| ]]''<br />
|-<br />
| Nov. 21 <br />
|[http://TBD Cancelled due to Thanksgiving] <br />
|''[[#Nov 21: Cancelled| ]]''<br />
|-<br />
| Nov. 28 <br />
|[http://TBD Xiaowu Dai] (Statistics) <br />
|''[[#Nov 28: Xiaowu Dai (Statistics)| Toward the Theoretical Understanding of Large-batch Training in Stochastic Gradient Descent ]]''<br />
|-<br />
|<br />
|}<br />
<br />
<br />
== Abstract ==<br />
<br />
=== Sep 12: Ke Chen (Math) ===<br />
Inverse Problem in Optical Tomography<br />
<br />
I will briefly talk about my researches on the inverse problems of radiative transfer equations, which is usually used as a model to describe the transport of neutrons or other particles in a certain media. Such inverse problems considers the following question: given the knowledge of multiple data collected at the boundary of the domain of interest, is it possible to reconstruct the optical property of the interior of media? In this talk, I will show you that stability of this problem is deteriorating as the Knudsen number is getter smaller. The talk will be introductory and anyone graduate is welcome to join us.<br />
<br />
=== Sept 26: Kurt Ehlert (Math) ===<br />
How to bet when gambling<br />
<br />
When gambling, typically casinos have an edge. But sometimes we can gain an edge by counting cards or other means. And sometimes we have an edge in the biggest casino of all: the financial markets. When we do have an advantage, then we still need to decide how much to bet. Bet too little, and we leave money on the table. Bet too much, and we risk financial ruin. We will discuss the "Kelly criterion", which is a betting strategy that is optimal in many senses.<br />
<br />
=== Oct 10: Zachary Hansen (Atmospheric and Oceanic Sciences) ===<br />
Land-Ocean contrast in lightning<br />
<br />
Land surfaces have orders of magnitude more lightning flashes than ocean surfaces. One explanation for this difference is that land surfaces may generate greater convective available potential energy (CAPE), which fuels stronger thunderstorms. Using a high resolution cloud-resolving atmospheric model, we test whether an island can produce stronger thunderstorms just by having a land-like surface. We find that the island alters the distribution of rainfall but does not produce stronger storms. An equilibrium state known as boundary layer quasi-equilibrium follows, and is explored in more detail.<br />
<br />
=== Oct 24: Xuezhou Zhang (Computer Science) ===<br />
An Optimal Control Approach to Sequential Machine Teaching<br />
<br />
Given a sequential learning algorithm and a target model, sequential machine teaching aims to find the shortest training sequence to drive the learning algorithm to the target model. We present the first principled way to find such shortest training sequences. Our key insight is to formulate sequential machine teaching as a time-optimal control problem. This allows us to solve sequential teaching by leveraging key theoretical and computational tools developed over the past 60 years in the optimal control community. Specifically, we study the Pontryagin Maximum Principle, which yields a necessary condition for opti- mality of a training sequence. We present analytic, structural, and numerical implica- tions of this approach on a case study with a least-squares loss function and gradient de- scent learner. We compute optimal train- ing sequences for this problem, and although the sequences seem circuitous, we find that they can vastly outperform the best available heuristics for generating training sequences.<br />
<br />
=== Nov 7: Cancelled ===<br />
<br />
=== Nov 21: Cancelled ===<br />
<br />
=== Nov 28: Xiaowu Dai (Statistics) ===<br />
Toward the Theoretical Understanding of Large-batch Training in Stochastic Gradient Descent<br />
<br />
Stochastic gradient descent (SGD) is almost ubiquitously used for training nonconvex optimization tasks including deep neural networks. Recently, a hypothesis that "large batch SGD tends to converge to sharp minimizers of training function" has received increasing attention. We develop some new theory to give a justification of this hypothesis. In particular, we provide new properties of SGD in both finite-time and asymptotic regimes, with the tools from empirical processes and Partial Differential Equations. A connection between the stochasticity in SGD and the idea of smoothing splines in nonparametric statistics is also built. We include numerical experiments to corroborate these theoretical findings.</div>Jeanluchttps://www.math.wisc.edu/wiki/index.php/Applied/ACMS/absS20Applied/ACMS/absS202019-11-04T15:08:24Z<p>Chennan: /* Hung Tran */</p>
<hr />
<div>= ACMS Abstracts: Spring 2020 =<br />
<br />
=== Hung Tran ===<br />
<br />
Title: Coagulation-Fragmentation equations with multiplicative coagulation kernel and constant fragmentation kernel<br />
<br />
Abstract: We study a critical case of Coagulation-Fragmentation equations with multiplicative coagulation kernel and constant fragmentation kernel. Our method is based on the study of viscosity solutions to a new singular Hamilton-Jacobi equation, which results from applying the Bernstein transform to the original Coagulation-Fragmentation equation. Our results include wellposedness, regularity and long-time behaviors of viscosity solutions to the Hamilton-Jacobi equation in certain regimes, which have implications to wellposedness and long-time behaviors of mass-conserving solutions to the Coagulation-Fragmentation equation. Joint work with Truong-Son Van (CMU).<br />
<br />
=== Curt A. Bronkhorst ===<br />
<br />
Title: Computational Prediction of Shear Banding and Deformation Twinning in Metals<br />
<br />
Abstract: The high deformation rate mechanical loading of polycrystalline metallic materials, which have ready access to plastic deformation mechanisms, generally involve an intense process of several deformation mechanisms within the material: dislocation slip (thermally activated and phonon drag dominated), recovery (annihilation and recrystallization), mechanical twinning, porosity, and shear banding depending upon the material. For this class of ductile materials, depending upon the boundary conditions imposed, there are varying degrees of porosity or adiabatic shear banding taking place at the later stages of the deformation history. Each of these two processes are as yet a significant challenge to predict accurately. This is true for both material models to represent the physical response of the material or the computational framework to represent accurately the creation of new surfaces or interfaces in a topologically independent way. Within this talk, I will present an enriched element technique to represent the adiabatic shear banding and deformation twinning process within a traditional Lagrangian finite element framework. A rate-dependent onset criterion for the initiation of a band is defined based upon a rate and temperature dependent material model. Once the bifurcation condition is met, the location and orientation of an embedded field zone is computed and inserted within a computational element. Once embedded the boundary conditions between the localized and unlocalized regions of the element are enforced and the composite sub-grid element follows a weighted average representation of both regions. Continuity in shear band growth is ensured by employing a non-local level-set technique connected to the displacement field within the finite-element solver. The material inside the band is able to be represented independent from the outside material and the thickness of the band can be assigned by any appropriate method. Dynamic recrystallization (DRX) is often observed in conjunction with adiabatic shear banding (ASB) in polycrystalline materials and is believed to be a critical softening mechanism contributing to the material instability. The recrystallized nanograins in the shear band have few dislocations compared to the material outside of the shear band. We reformulate a recently developed continuum theory of polycrystalline plasticity and include the creation of grain boundaries. While the shear-banding instability emerges because thermal heating is faster than heat dissipation, recrystallization is interpreted as an entropic effect arising from the competition between dislocation creation and grain boundary formation and is a significant softening mechanism. We show that our theory closely matches recent results in sheared 316L stainless steel. The theory thus provides a thermodynamically consistent way to systematically describe the formation of shear bands and recrystallized grains therein. The numerical tool has recently been applied to the modeling of deformation twinning in high-purity Ti which will be briefly discussed.</div>Qinlihttps://www.math.wisc.edu/wiki/index.php/Applied/Physical_Applied_Math/Spring2019Applied/Physical Applied Math/Spring20192019-10-29T08:57:43Z<p>Jeanluc: Created page with "== Spring 2019 == {| cellpadding="8" !align="left" | date !align="left" | speaker !align="left" | title |- |Jan. 24 | |''Faculty Meeting'' |- |Jan. 31 |Jean-Luc |Organizati..."</p>
<hr />
<div>== Spring 2019 ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
|-<br />
|Jan. 24<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Jan. 31<br />
|Jean-Luc<br />
|Organizational meeting; J-LT speaks on Vortices in a channel<br />
|-<br />
|Feb. 7<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Feb. 14<br />
|Yu<br />
|Suppression of phase separation by mixing<br />
|-<br />
|Feb. 21<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Feb. 28<br />
|Bryan<br />
|Riffles shuffles and mixing<br />
|-<br />
|Mar. 7<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Mar. 14<br />
|Hongfei<br />
|[https://www.springer.com/us/book/9781441916044 Diffusion across potential barriers]<br />
|-<br />
|Mar. 21<br />
|<br />
|''Spring Break''<br />
|-<br />
|Mar. 28<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Apr. 4<br />
|Ruojun<br />
|Internal diffusion-limited aggregation and rotor-router walks with drift<br />
|-<br />
|Apr. 11<br />
|Jiajia<br />
|[https://doi.org/10.1063/1.1675038 Freed, Wiener Integrals and Models of Stiff Polymer Chains]<br />
|-<br />
|Apr. 18<br />
|Wangping<br />
|Entanglement of frictionless strings<br />
|-<br />
|Apr. 25<br />
|John<br />
|pseudo-Anosov homeomorphisms with large entropy<br />
|-<br />
|May 2<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|May 9<br />
|Saverio<br />
|Internal capillary origami (see [https://journals.aps.org/pra/abstract/10.1103/PhysRevA.44.1182 Seifert et al, Shape transformations of vesicles] and [https://www.annualreviews.org/doi/full/10.1146/annurev-fluid-122316-050130?casa_token=lYj2Hmpn0fEAAAAA:269tjv-n7Odyzgam7PniTi5WmNPjP0qVrO7qxV0a8Ox_Tl4fNsawlxTves-ev7vI_h9Sx_0jKfwK Bico et al., Elastocapillarity (Review article)])<br />
|-<br />
|}</div>Jeanluchttps://www.math.wisc.edu/wiki/index.php/Applied/Physical_Applied_Math/Fall2018Applied/Physical Applied Math/Fall20182019-10-29T08:56:53Z<p>Jeanluc: Created page with "== Fall 2018 == {| cellpadding="8" !align="left" | date !align="left" | speaker !align="left" | title |- |Jan. 31 |Jean-Luc |Organizational meeting; J-LT speaks on Aldous a..."</p>
<hr />
<div>== Fall 2018 ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
|-<br />
|Jan. 31<br />
|Jean-Luc<br />
|Organizational meeting; J-LT speaks on Aldous and Diaconis, [https://www.ams.org/journals/bull/1999-36-04/S0273-0979-99-00796-X/ Longest increasing subsequences: from patience sorting to the Baik-Deift-Johansson theorem]<br />
|-<br />
|Sep. 13<br />
|Son<br />
|[https://arxiv.org/abs/1808.06129 Rate of convergence for periodic homogenization of convex Hamilton-Jacobi equations in one dimension]<br />
|-<br />
|Sep. 20<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Sep. 27<br />
|[https://www.math.cmu.edu/~gautam/sj/index.html Gautam Iyer] (CMU)<br />
|[https://arxiv.org/abs/1806.03699 Dissipation enhancement by mixing]<br />
|-<br />
|Oct. 4<br />
|Gage<br />
|[https://www.dropbox.com/s/tjc4v03cwgzeppm/Group_talk_ab___notes.pdf Escape rates of random walks on free groups]<br />
|-<br />
|Oct. 11<br />
|<i>cancelled</i><br />
|<br />
|-<br />
|Oct. 18<br />
|Yu Feng<br />
|Relaxation enhancement for Advective Cahn-Hilliard (practice for specialty)<br />
|-<br />
|Oct. 25<br />
|Yu's specialty <b>2-3pm, B139</b><br />
|Relaxation enhancement for Advective Cahn-Hilliard<br />
|-<br />
|Nov. 1<br />
|Wil<br />
|Powers, [https://journals.aps.org/rmp/abstract/10.1103/RevModPhys.82.1607; Dynamics of filaments and membranes in a viscous fluid]; Guven et al. [http://iopscience.iop.org/article/10.1088/1751-8113/47/35/355201/pdf Environmental bias and elastic curves on surfaces]<br />
|-<br />
|Nov. 8<br />
|Tom<br />
|[https://arxiv.org/abs/1809.01190 Mixing by jellyfish]<br />
|-<br />
|Nov. 15<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|Nov. 22<br />
|<br />
|''Thanksgiving Break''<br />
|-<br />
|Nov. 29<br />
|Chris<br />
|Sun et al., [https://www.sciencedirect.com/science/article/pii/S0167278911001588 A mathematical model for the synchronization of cows]<br />
|-<br />
|Dec. 6<br />
|<br />
|''Faculty Meeting''<br />
|-<br />
|'''Dec. 12, B239'''<br />
|Jean-Luc<br />
|Cooking food by flipping<br />
|-<br />
|Dec. 13<br />
|<br />
|''Faculty Meeting''<br />
|}</div>Jeanluc