Tue, 17 Oct 2017

15:45 - 16:45
L4

From period integrals to toric degenerations of Fano manifolds

Thomas Prince
(Oxford)
Abstract

Given a Fano manifold we will consider two ways of attaching a (usually infinite) collection of polytopes, and a certain combinatorial transformation relating them, to it. The first is via Mirror Symmetry, following a proposal of  Coates--Corti--Kasprzyk--Galkin--Golyshev. The second is via symplectic topology, and comes from considering degenerating Lagrangian torus fibrations. We then relate these two collections using the Gross--Siebert program. I will also comment on the situation in higher dimensions, noting particularly that by 'inverting' the second method (degenerating Lagrangian fibrations) we can produce topological constructions of Fano threefolds.
 

Preface Abate, A Geeraerts, G (01 Jan 2017)
Automated Experiment Design for Data-Efficient Verification of Parametric Markov Decision Processes
Polgreen, E Wijesuriya, V Haesaert, S Abate, A Lecture Notes in Computer Science volume 10503 259-274 (11 Aug 2017)
Aggregated Markov models of a heterogeneous population of photovoltaic panels
Peruffo, A Guiu, E Panciatici, P Abate, A QEST 2017: Quantitative Evaluation of Systems volume 10503 72-87 (11 Aug 2017)
Tue, 06 Feb 2018
14:15
L4

Dual singularities in exceptional type nilpotent cones

Paul Levy
(University of Lancaster)
Abstract

It is well-known that nilpotent orbits in $\mathfrak{sl}_n(\mathbb C)$ correspond bijectively with the set of partitions of $n$, such that the closure (partial) ordering on orbits is sent to the dominance order on partitions. Taking dual partitions simply turns this poset upside down, so in type $A$ there is an order-reversing involution on the poset of nilpotent orbits. More generally, if $\mathfrak g$ is any simple Lie algebra over $\mathbb C$ then Lusztig-Spaltenstein duality is an order-reversing bijection from the set of special nilpotent orbits in $\mathfrak g$ to the set of special nilpotent orbits in the Langlands dual Lie algebra $\mathfrak g^L$.
It was observed by Kraft and Procesi that the duality in type $A$ is manifested in the geometry of the nullcone. In particular, if two orbits $\mathcal O_1<\mathcal O_2$ are adjacent in the partial order then so are their duals $\mathcal O_1^t>\mathcal O_2^t$, and the isolated singularity attached to the pair $(\mathcal O_1,\mathcal O_2)$ is dual to the singularity attached to $(\mathcal O_2^t,\mathcal O_1^t)$: a Kleinian singularity of type $A_k$ is swapped with the minimal nilpotent orbit closure in $\mathfrak{sl}_{k+1}$ (and vice-versa). Subsequent work of Kraft-Procesi determined singularities associated to such pairs in the remaining classical Lie algebras, but did not specifically touch on duality for pairs of special orbits.
In this talk, I will explain some recent joint research with Fu, Juteau and Sommers on singularities associated to pairs $\mathcal O_1<\mathcal O_2$ of (special) orbits in exceptional Lie algebras. In particular, we (almost always) observe a generalized form of duality for such singularities in any simple Lie algebra.
 

Full counting statistics in the spin-1/2 Heisenberg XXZ chain
Collura, M Essler, F Groha, S JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL volume 50 issue 41 (13 Oct 2017)
Wed, 17 Jan 2018
15:00
L4

Past and Future of Embedded Security: From Self-driving Cars to Transistor Trojans

Christof Paar
(Ruhr-Uni­ver­si­tät Bo­chum)
Abstract

With the evolution towards the IoT and cyber-physical systems, the role that the underlying hardware plays in securing an application is becoming more prominent. Hardware can be used constructively, e.g. for accelerating computationally- intensive cryptographic algorithms. Hardware can also be used destructively, e.g., for physical attacks or transistor-level Trojans which are virtually impossible to detect. In this talk, we will present case studies for high-speed cryptography used in car2x communication and recent research on low-level hardware Trojans. 

Thu, 02 Nov 2017

12:00 - 13:00
L4

Acoustic and electromagnetic transmission problems

Euan Spence
(University of Bath)
Abstract

In this talk I will discuss acoustic and electromagnetic transmission problems; i.e. problems where the wave speed jumps at an interface. I will focus on what is known mathematically about resonances and trapped waves (e.g. When do these occur? When can they be ruled out? What do we know in each case?). This is joint work with Andrea Moiola (Pavia).

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