Workshop on Gromov-Witten Theory

This is a one-day event featuring some speakers from Northwestern and UIUC. 

Registration information below.

SCHEDULE (all talks in Lunt 104)

9:30-9:45 Milling around (NB: coffee not served, so bring your own!)

9:45-10:45 Sheldon Katz (UIUC)

11:00-12:00 Felix Janda (UIUC)

12:00-1:45 LUNCH (included for participants; reservation at Mt. Everest at 12:15pm)

1:45-2:45 Deniz Genlik (UIUC)

3:00-3:30 Eric Zaslow (Northwestern)

TITLES AND ABSTRACTS

Sheldon Katz

Title: Wavefunctions and enumerative geometry

Abstract: Assuming no knowledge of physics, I will introduce wavefunctions and then explain how they enter into enumerative geometry.  This is an expository talk containing no new results.

Felix Janda

Title:  The tropical geometry of log GLSM

Abstract:  Log GLSM is a curve-counting theory related to Gromov-Witten theory.

I will introduce a fundamental structural formula in log GLSM called the tropical decomposition formula. This formula specializes to a quantum Lefschetz type formula, which computes the Gromov-Witten invariants of a complete intersection in terms of enumerative invariants of its ambient space and "effective invariants". As an application, I will show how this leads to a geometric polynomiality for the Gromov-Witten generating function of any Calabi-Yau threefold hypersurface.

This is a joint work with Qile Chen and Yongbin Ruan.

Deniz Genlik

Title: Divisors on M_{0,n} and linear programming polytopes

Abstract: We define the polytopes of effective boundary representations for divisors on M_{0,n}. We show certain functoriality properties of these polytopes under the forgetful maps of marked points. We compute these polytopes for log canonical class, psi classes and their pullbacks by forgetful maps. Lastly, as an application, we provide a Minkowski-like decomposition of Held-Karp relaxation polytope of symmetric traveling salesman problem.

Eric Zaslow

Title:  Some simple counts of nodal curves

Abstract:  In this short talk, I want to explain a few nuts and bolts of how to calculate a certain logarithmic Gromov-Witten invariant by localization, as well as a dual constructible-sheaf calculation.  These calculations are part of a joint work in progress with Tom Graber and Mingyuan Hu.

Information for Participants Requesting Reimbursement

Northwestern People:  lunch will be reimbursed if you go with the group to Mt. Everest

Visitors:  day's expenses reimbursed up to $100 if funds last; fill out Expense Form

Instructions for filling out above expense form:

Visitor expense reports and their accompanying documents must be submitted within 45 days of the workshop/conference conclusion to ensure full reimbursement.Reimbursement note – Flights must be booked in compliance with the Fly America Act. Meaning U.S. flag air carriers. If you have any questions or concerns about booking, please contact Alicia in the Northwestern Mathematics Department before purchasing your ticket.  

1. Complete Visitor Expense Form. Fill out all required fields on the VER Form. Your form must include:

Name, mailing address, and phone number.
Inclusive dates of travel or Expenses.
All expenses being claimed, with amounts matching the itemized receipts provided. Each receipt must show the last 4 digits of the card used for purchase. If you lost a receipt, please include a printout of the debit/credit card statement and any vendor documentation, and state this in your email. Please note that if a purchase is split between participants for lodging/transportation, include the original receipt and proof of payment to the cardholder (via Zelle, Venmo, etc.).
Mileage: Specify where mileage was incurred. Send a printout of Google Maps directions.
Digital or Wet Signature required (typed or computer-generated signatures not acceptable) and date.
2. Reimbursement Payout Options: Reimbursements can be issued by check, Zelle, or wire transfer. Please indicate your preferred method in your email. If the payment method is not specified, reimbursement will be processed by check.

Check – Please ensure you have the proper mailing address on your Visitor expense form.
Zelle – Must have a US Mailing address and a US Bank Account. Indicate your email address; phone numbers are not accepted.
Wire Transfer – Additional Information will be required.
3. Submit All Forms and Receipts

Email your complete Expense Form and all receipts to Alicia Lederer at Alicia.lederer@northwestern.edu.

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