2018 Nov 20

# T&G: Gangotryi Sorcar (Hebrew University), On the topology of the Teichmuller space of negatively curved Riemannian metrics

2:00pm to 3:30pm

## Location:

Room 209, Manchester Building, Jerusalem
This talk is a survey on results concerning the Teichmuller space of negatively curved Riemannian metrics on M. It is defined as the quotient space of the space of all negatively curved Riemannian metrics on M modulo the space of all isotopies of M that are homotopic to the identity. This space was shown to have highly non-trivial homotopy when M is real hyperbolic by Tom Farrell and Pedro Ontaneda in 2009.
2018 Nov 21

# Set Theory Seminar: Yair Hayut "Chang's Conjecture"

2:00pm to 3:30pm

## Location:

Ross 63
Title: Chang's Conjecture (joint with Monroe Eskew) Abstract: I will review some consistency results related to Chang's Conjecture (CC). First I will discuss some classical results of deriving instances of CC from huge cardinals and the new results for getting instances of CC from supercompact cardinals, and present some open problems. Then, I will review the consistency proof of some versions of the Global Chang's Conjecture - which is the consistency of the occurrence many instances of CC simultaneously. We will aim to show the consistency of the statement: (\mu^+,\mu) -->> ( u^+,
2018 Nov 19

# NT&AG: Gaku Liu (Max Planck Institute of Mathematics), "Semistable reduction in characteristic 0"

2:30pm to 4:00pm

## Location:

Room 70A, Ross Building, Jerusalem, Israel
We address the semistable reduction conjecture of Abramovich and Karu: we prove that every surjective morphism of complex projective varieties can be modified to a semistable one. The key ingredient is a combinatorial result on triangulating lattice Cayley polytopes. Joint work with Karim Adiprasito and Michael Temkin. The lecture consists of two parts: first 30 minutes an algebra-geometric introduction by Michael Temkin, and then a one hour talk by Gaku Liu about the key combinatorial result.
2018 Nov 20

# Dynamics Lunch: Jiange Li "Sumsets and entropy" after Ruzsa

12:00pm to 1:00pm

## Location:

Manchester faculty club
2018 Dec 05

# Logic Seminar - Omer Ben-Neria

11:00am to 1:00pm

Ross 63
tba

2018 Nov 14

# Logic Seminar - Yair Hayut

11:00am to 1:00pm

## Location:

Ross 63

Global Chang's Conjecture

Yair Hayut - (joint with Monroe Eskew)

For $\kappa < \lambda$ infinite cardinals let us consider the following generalization of the Lowenheim-Skolem theorem:
"For every algebra with countably many operations over $\lambda^+$ there is a sub-algebra with order type exactly $\kappa^+$".

We will discuss the consistency and inconsistency of some global versions of this statement and present some open questions.
2018 Dec 19

# Logic Seminar - Menachem Magidor

11:00am to 1:00pm

Ross 63
tba

2018 Dec 10

1:00pm to 2:00pm

2018 Nov 26

1:00pm to 2:00pm

2018 Nov 19

# NT & AG Lunch: Sazzad Biswas "Local gamma factors, and converse problems"

1:00pm to 2:00pm

## Location:

Faculty lounge, Math building
Let F be a non-Archimedean local field. In the representation theory of GL_n(F), one of the basic problems is to characterize its irreducible representations up to isomorphism. There are many invariants (e.g., epsilon factors, L-functions, gamma factors, depth, etc) that we can attach to a representation of GL_n(F). Roughly, the local converse problem is to find the smallest subcollection of twisted local \gamma-factors which classifies the irreducible admissible representations of GL_n(F) up to isomorphism.
2019 Jan 14

1:00pm to 2:00pm

2018 Dec 17

1:00pm to 2:00pm

2018 Dec 03

1:00pm to 2:00pm

2019 Jan 07

1:00pm to 2:00pm

2018 Dec 31

1:00pm to 2:00pm