Thu, 19 Jan 2017
11:00
C5

Towards a Ladder Theorem for Specialisations

Ugur Efem
Abstract


In this talk I will present some answers to the question when every specialisation from a \kappa-saturated extension of 
a Zariski structure is \kappa-universal? I will show that for algebraically closed fields, all specialisations from a \kappa-
saturated extension is \kappa-universal. More importantly, I will consider this question for finite and infinite covers of
Zariski structures. In these cases I will present a counterexample to show that there are covers of Zariski structures 
which have specialisations from a \kappa-saturated extension that are not \kappa-universal. I will present some natural 
conditions on the fibres under which all specialisations from a \kappa-saturated extension of a cover is \kappa-universal. 
I will explain how this work points towards a prospective Ladder Theorem for Specialisations and explain difficulties and 
further works that needs to be considered.
 

Fri, 17 Feb 2017

17:00 - 18:00
L2

InFoMM The Reddick Lecture

Tom Hebbert
(Supply Chain Director at Tesco PLC)
Abstract

Data science: The secret to unlocking operational performance within the UK’s largest retail supply chain

 

Chris Reddick was instrumental in setting up the InFoMM CDT. After helping secure the EPSRC funding he chaired the Industrial Engagement Committee and supported the CDT in all its Industrial relations. The success of the CDT, as evidenced by the current size of the industrial partnership and the vibrant programme we have developed, is in no small part due to Chris' charm, vision, and tenacity.

Tue, 24 Jan 2017
14:30
L6

Gowers Norms of the Thue-Morse and Other Automatic Sequences

Jakub Konieczny
(Oxford University)
Abstract

The Thue-Morse sequence is perhaps the simplest example of an automatic sequence. Various pseudorandomness properties of this sequence have long been studied. During the talk, I will discuss a new result in this direction, asserting that the Gowers uniformity norms of the Thue-Morse sequence are small in a quantitative sense. Similar results hold for the Rudin-Shapiro sequence, as well as for a much wider class of automatic sequences which will be introduced during the talk.

The talk is partially based on joint work with Jakub Byszewski.

Thu, 02 Feb 2017
17:30
L6

On algebraically closed fields of characteristic 1

Boris Zilber
(Oxford)
Abstract

I will start with a motivation of what algebraic and model-theoretic properties an algebraically closed field of characteristic 1 is expected to have. Then I will explain how these properties forces one to follow the route of Hrushovski's construction/Schanuel-type conjecture analysis. Then I am able to formulate very precise axioms that such a field must satisfy.  The main theorem then states that under the axioms the structure has the desired algebraic properties.
The axioms have a form of statements about existence of solutions to systems of equations in terms of a 'multi-dimansional' valuation theory and the validity of these statements is an open problem to be discussed. 

 

Wed, 03 May 2017
15:00
L4

Verifiable Electronic Voting in Practice

Feng Hao
(Newcastle University)
Abstract

In this talk, I’ll share the progress that we have made in the field of e-voting, including the proposal of a new paradigm of e-voting system called self-enforcing e-voting (SEEV). A SEEV system is End-to-End (E2E) verifiable, but it differs from all previous E2E systems in that it does not require tallying authorities. The removal of tallying authorities significantly simplifies the election management and makes the system much more practical than before. A prototype of a SEEV system based on the DRE-i protocol (Hao et al. USENIX JETS 2014) has been built and used regularly in Newcastle University for classroom voting and student prize competitions with very positive student feedback. Lessons from our experience of designing, analysing and deploying an e-voting system for real-world applications are also presented.

Tue, 07 Mar 2017
15:45
L4

Local cohomology and canonical stratification

Vidit Nanda
(Oxford)
Abstract

Every finite regular CW complex is, ipso facto, a cohomologically stratified space when filtered by skeleta. We outline a method to recover the canonical (i.e., coarsest possible) stratification of such a complex that is compatible with its underlying cell structure. Our construction proceeds by first localizing and then resolving a complex of cosheaves which capture local cohomology at every cell. The result is a sequence of categories whose limit recovers the desired strata via its (isomorphism classes of) objects. As a bonus, we observe that the entire process is algorithmic and amenable to efficient computations!

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