Activities This Week
AGNT
l-Adic local systems and Higgs bundles Online
Jun 5, 12:10—13:10, 2023, -101
Speaker
Hongjie Yu (Weizmann)
Abstract
In 1981, Drinfeld enumerated the number of irreducible l-adic local systems of rank two on a projective smooth curve in positive characteristic fixed by the Frobenius endomorphism. Interestingly, this number bears resemblance to the number of points on a variety over a finite field. Deligne proposed conjectures to extend and comprehend Drinfeld’s result. In this talk, I will present Deligne’s conjectures and discuss some mysterious phenomena that have emerged in various cases where this number is related to the number of stable Higgs bundles.
Colloquium
Teichmuller spaces for geometric structures and the mapping class group action
Jun 6, 14:30—15:30, 2023, Math -101
Speaker
Misha Verbitsky (IMPA)
Abstract
The Teichmuller space of geometric structures of a given type is a quotient of the (generally, infinite-dimensional) space of geometric structures by the group of isotopies, that is, by the connected component of the diffeomorphism group. In several important qand smooth.uestions, such as for symplectic, hyperkahler, Calabi-Yau, G2 structures, this quotient is finite-dimenisional and even smooth. The mapping class group acts on the Teichmuller space by natural diffeomorphisms, and this action is in many important situations ergodic (in particular, it has dense orbits), bringing strong consequences for the geometry. I would describe the Teichmuller space for the best understood cases, such as symplectic and hyperkahler manifolds, and give a few geometric applications.
אשנב למתמטיקה
צמות, קשרים, חבורות ומה שביניהם Online
Jun 6, 18:10—19:30, 2023, אולם 101-, בניין מתמטיקה
Speaker
מיכאל ברנדנבורסקי
Abstract
בהרצאה נדון בהעתקות מעניינות מחבורה כלשהיא לתוך הממשיים שנקראות קואזי-מורפיזמים. נראה שימושים שלהן בהרבה ענפים של מתמטיקה כגון: תורת הקשרים, תורת החבורות, גאומטריה וטופולוגיה
BGU Probability and Ergodic Theory (PET) seminar
TBA
Jun 8, 11:10—12:00, 2023, -101