The ninth meeting of the South East Mathematical Physics Seminar will be held on Monday 17th July 2017 at King's College London in room K3.11. The meeting is partially supported by supported by a London Mathematical Society Joint Research Groups grant.
There is no registation fee, and no need to register in advance, but currently all visitors to King's are required to sign in at reception, and it would be very helpful and speed matters up if we knew who was coming in advance. Please email Gerard Watts if you are likely to attend.
13.30 - 14.00 | Coffee | ||
14.00 - 14.50 | E.-M. Graefe | ||
14.50 - 15.40 | M. Collura | ||
15.40 - 16.10 | Coffee | ||
16.10 - 17.00 | J.P. Garrahan |
Mario Collura (Oxford) | |
Non-equilibrium transport in the XXZ spin-1/2 chain: Domain-Wall analytic solution | |
Juan P Garrahan (Nottingham) | |
Boundary driven open quantum chains: fluctuating hydrodynamics, large deviations and hyperuniformity | |
I will consider the problem of quantum chains driven by dissipative interactions at the boundaries - and subject to dissipation at the bulk - in order to study the interplay between coherent and dissipative processes in their transport. I will discuss how dynamics on large scales can be described in terms of fluctuating hydrodynamics, in analogy with what is done in classical exclusion processes. This is an important simplification as it allows to apply the methods of macroscopic fluctuation theory to compute the large deviation statistics of time-integrated currents and dynamical activities. For the case of fermionic chains, singularities in large deviation functions indicate the existence of distinct dynamical phases and phase transitions between them at the fluctuation level, manifested in singular changes in the structure of dynamical trajectories. I will discuss how these results fit more broadly in the application of classical ideas to open quantum non-equilibrium systems. | |
Eva-Maria Graefe (Imperial) | |
PT-symmetric random matrix ensembles using split-quaternionic numbers | |
Random matrices play a crucial role in various fields of mathematics and physics. In particular in the field of quantum chaos Hermitian random matrix ensembles represent universality classes for spectral features of Hamiltonians with classically chaotic counterparts. In recent years the study of non-Hermitian but PT-symmetric quantum systems has attracted a lot of attention. These are non-Hermitian systems that have an anti-unitary symmetry, which is often interpreted as a balance of loss and gain in a system. In this talk the question of whether and how the standard ensembles of Hermitian quantum mechanics can be modified to yield PT-symmetric counterparts is addressed. In particular it is argued that using split-complex and split-quaternionic numbers two new PT-symmetric random matrix ensembles can be constructed. These matrices have either real or complex conjugate eigenvalues, the statistical features of which are analysed for 2 × 2 matrices. | |
The meeting is in room K3.11, on the third floor of the King's building. Here is a map of the campus [the King's building is in red] and a map of the second floor of the King's building
Local travel information may also be found here.
London transport information is available here. The nearest tube station is Temple; other stations within walking distance are Embankment, Charing Cross, Covent Garden and Holborn.
Train information may be obtained from here. The nearest national rail stations are Charing Cross, Waterloo & Waterloo East, Blackfriars and City Thameslink.
Limited funds are available to help with travel expenses of participants with no other source of funding. We hope that this will encourage postgraduate students and postdocs to attend the meeting. Please email Clare Dunning (tcd at kent.ac.uk) in advance if you would like to apply for support. A claim form is available here
To return to the South East Mathematical Physics Seminar webpage and to find information about claiming travel expenses please follow this link.
Go to the Department of Mathematics home page.
The second meeting of the
South East Mathematical Physics Seminar will be held on
Thursday 15th May 2014
at King's College London in room K2.31. The meeting is partially supported by
supported by a London Mathematical
Society Joint
Research Groups grant.
There is no registatrion or fee, but it would be helpful for ordering the right amount of coffee if you could email Gerard Watts if you are likely to go
11.00 - 11.30 | Coffee | ||
11.30 - 12.30 | Leron Borsten | A magic pyramid of supergravities | |
12.30 - 13.30 | lunch | ||
13.30 - 14.30 | Paul Sutcliffe | Magnetic vortex rings | |
14.30 - 15.30 | Vidas Regelskis | Twisted Yangians for symmetric pairs of types B, C, D | |
15.30 - 16.00 | Tea & Biscuits | ||
16.00 - 16.45 | Abera Muhamed | Moduli spaces of lumps on the projective plane RP^3 | |
16.45 - 17.30 | Craig Lawrie | Box Graphs and Singular Fibers |
Leron Borsten (Imperial) | ||
A magic pyramid of supergravities | ||
The octonions occupy a privileged position as the largest of the division algebras A (reals R, complexes C, quaternions H and octonions O) and provide an intuitive basis for the exceptional Lie groups. Efforts to understand the exceptional groups geometrically in terms of octonions resulted in the Freudenthal-Rozenfeld-Tits magic square; a symmetric four-by-four (A1, A2) array of semi-simple Lie algebras. The octonionic row (A1= O, A2 = R, C, H, O) is exceptional: F4, E6, E7, E8. We begin with an elementary introduction to division algebras and magic squares. Then we will give a R, C, H, O description of D = 3 Yang-Mills with N = 1, 2, 4, 8. Tensoring left and right Yang-Mills multiplets yields an array of D = 3 supergravity with N = 2, 3, 4, 5, 6, 8, 9, 10, 12, 16. For N> 8 the multiplets are those of pure supergravity, while for N<9 they are coupled to matter. In both cases the field content is such that the U-dualities exactly match the magic square! We conclude by generalising to D=4,6 and 10 introducing a magic pyramid of Lie algebras, which depends on 3 division algebras, one fixed by spacetime the other two inherited from left/right Yang-Mills theories. | ||
Craig Lawrie (KCL) | ||
Box Graphs and Singular Fibers | ||
We study crepant resolutions of singular elliptically fibered Calabi-Yau fourfolds by analysing the phases of the Coulomb branch of the 3d N=2 gauge theories arising from the compactification of M-theory on the Calabi-Yau. Each phase corresponds to a particular resolution of the singular fourfold and has a description in terms of a 'decorated box graph', or a path on such a graph. The phases are related by deformations of this path, called flops, which correspond to geometric flop transitions between the resolved geometries. Using these techniques we can determine all the resolved geometries and the transitions between them, and we can enumerate the fiber types in codimensions 2 and 3, including new, non-Kodaira, fiber types. | ||
Abera Muhamed (Canterbury) | ||
Moduli spaces of lumps on the projective plane RP^3 | ||
The CP^2 sigma model is a non-linear field theory possessing topological solitons, called lumps. The energy E and topological degree N satisfying the Bogomolny bound E >= Pi |N|, The CP^2 sigma model can be defined on a Riemann surface. Here we will discuss lumps on the projective plane RP^2. Then the module space of solutions is given by a subset of rational maps. We first discuss the geometry and topology of rational maps as well as an explicit description. We also discuss the moduli psace of charge three lumps with symmetry in detail. Surprisingly, only three types of symmetry occur, namely axial, dihderal and the non-symmetric | ||
Vidas Regelskis (Surrey) | ||
In this talk I will present the a class of quantized enveloping algebras, called twisted Yangians, associated with the symmetric pairs of types B, C, D in terms of the Cartan classification of compact Riemannian symmetric spaces. These algebras play an important role in quantum integrable systems with open boundary conditions. They are regarded as coideal subalgebras of the extended Yangian for orthogonal or symplectic Lie algebras, whose defining relations are written in an R-matrix form. On the other hand, these algebras can be presented as quotients of the reflection equation algebra by additional symmetry relations. | ||
Paul Sutcliffe (Durham) | ||
Magnetic Vortex Rings | ||
The meeting is in room K2.31, on the second floor of the King's building. Here is a map of the campus [the King's building is in red] and a map of the second floor of the King's building
Local travel information including maps may be found here.
London transport information is available here. The nearest The station is Temple; other stations in walking distance are Embankment, Charing Cross, Covent Garden and Holborn.
Train information may be obtained from here. The nearest national rail stations are Charing Cross, Waterloo & Waterloo East, Blackfriars and City Thameslink.
Limited funds are available to help with travel expenses of participants with no other source of funding. We hope that this will encourage postgraduate students and postdocs to attend the meeting. Please email Clare Dunning (tcd at kent.ac.uk) in advance if you would like to apply for support.
To return to the South East Mathematical Physics Seminar webpage and to find information about claiming travel expenses please follow this link.
Go to the Department of Mathematics home page.