2019
Jun
26

# Logic Seminar - Nick Ramsey

11:00am to 1:00pm

## Location:

Ross 63

Possibilities for a theory of independence beyond NSOP_1 and NTP_2

2019
Jun
26

11:00am to 1:00pm

Ross 63

Possibilities for a theory of independence beyond NSOP_1 and NTP_2

2019
Mar
20

11:00am to 1:00pm

Ross 63

2019
Jun
19

11:00am to 1:00pm

Ross 63

2019
May
29

2019
May
01

2019
May
15

11:00am to 1:00pm

Ross 63

We will try to prove two results about the possible cofinality of cardinal characteristics.

The first result is about the ultrafilter number, and this is a part of a joint work with Saharon Shelah.

The second is about Galvin's number, and this is a joint work with Yair Hayut, Haim Horowitz and Menachem Magidor.

2019
Mar
27

11:00am to 1:00pm

Ross 63

Uniform definability of types over finite sets (UDTFS) is a property of formulas which implies NIP and characterizes NIP in the level of theories (by Chernikov and Simon).

In this talk we will prove that if T is any theory with definable Skolem functions, then every dependent formula phi has UDTFS. This result can be seen as a translation of a result of Shay Moran and Amir Yehudayof in machine learning theory to the logical framework.

2019
Mar
18

Repeats every week every Monday until Mon Apr 29 2019 except Mon Apr 22 2019.

4:00pm to 6:00pm4:00pm to 6:00pm

4:00pm to 6:00pm

4:00pm to 6:00pm

4:00pm to 6:00pm

4:00pm to 6:00pm

Ross 70

Abstract. This is a joint work with Linhui Shen.

A decorated surface is an oriented surface with punctures and a finite collection of special points on the boundary, considered modulo isotopy.

Let G be a split adjoint group. We introduce a moduli space Loc(G,S) of G-local systems on a decorated surface S, which reduces to the character variety when S has no boundary, and quantize it.

2019
Mar
18

1:00pm to 2:00pm

Faculty lounge, Math building

Class field theory classifies abelian extensions of local and global fields

in terms of groups constructed from the base. We shall survey the main results of class

field theory for number fields and function fields alike. The goal of these introductory lectures

is to prepare the ground for the study of explicit class field theory in the function field case,

via Drinfeld modules.

I will talk for the first 2 or 3 times.

in terms of groups constructed from the base. We shall survey the main results of class

field theory for number fields and function fields alike. The goal of these introductory lectures

is to prepare the ground for the study of explicit class field theory in the function field case,

via Drinfeld modules.

I will talk for the first 2 or 3 times.

2019
Apr
02

2019
Mar
18

2:30pm to 3:30pm

Room 70A, Ross Building, Jerusalem, Israel

There is a general slogan according to which the limit behaviour of a one-parameter family of complex algebraic varieties when the parameter t tends to zero should be (partially) encoded in the associated t-adic analytic space in the sense of Berkovich; this slogan has given rise to deep and fascinating conjecturs by Konsevich and Soibelman, as well as positive results by various authors (Berkovich, Nicaise, Boucksom, Jonsson...).

2019
Mar
13

2019
May
15

2:00pm to 3:30pm

Ross 63

Abstract: We combine a technique of Steel with one due to Jensen and Steel to

obtain a core model below singular cardinals kappa which are

sufficiently closed under the beth function, assuming that there is no

premouse of height kappa with unboundedly many Woodin cardinals.

The motivation for isolating such core model is computing a lower bound for the strength of

the theory: T = ''ZFC + there is a singular cardinal kappa such that the set of ordinals below kappa where GCH holds is stationary and co-stationary''.

obtain a core model below singular cardinals kappa which are

sufficiently closed under the beth function, assuming that there is no

premouse of height kappa with unboundedly many Woodin cardinals.

The motivation for isolating such core model is computing a lower bound for the strength of

the theory: T = ''ZFC + there is a singular cardinal kappa such that the set of ordinals below kappa where GCH holds is stationary and co-stationary''.

2019
May
22

2:00pm to 3:30pm

Ross 63

Abstract: We combine a technique of Steel with one due to Jensen and Steel to

obtain a core model below singular cardinals kappa which are

sufficiently closed under the beth function, assuming that there is no

premouse of height kappa with unboundedly many Woodin cardinals.

The motivation for isolating such core model is computing a lower bound for the strength of

the theory: T = ''ZFC + there is a singular cardinal kappa such that the set of ordinals below kappa where GCH holds is stationary and co-stationary''.

obtain a core model below singular cardinals kappa which are

sufficiently closed under the beth function, assuming that there is no

premouse of height kappa with unboundedly many Woodin cardinals.

The motivation for isolating such core model is computing a lower bound for the strength of

the theory: T = ''ZFC + there is a singular cardinal kappa such that the set of ordinals below kappa where GCH holds is stationary and co-stationary''.

2019
Mar
12

1:00pm to 2:30pm

Room 110, Manchester Building, Jerusalem, Israel

I will discuss results relating different partially wrapped Fukaya categories. These include a K\"unneth formula, a `stop removal' result relating partially wrapped Fukaya categories relative to different stops, and a gluing formula for wrapped Fukaya categories. The techniques also lead to generation results for Weinstein manifolds and for Lefschetz fibrations. The methods are mainly geometric, and the key underlying Floer theoretic fact is an exact triangle in the Fukaya category associated to Lagrangian surgery along a short Reeb chord at infinity.