Triangle Seminars
Monday, 22 May 2023
LonTI: Leverhulme Lectures on Supersymmetry, complex geometry and the hyperkahler quotient
Ulf Lindstrom
(Uppsala)
Abstract:
Sigma models are maps from a domain to a target space T. The geometry of the target space is determined by the dimension of the domain and symmetries of the model. When it has isometries that can be gauged, the quotient space, i.e., the space of orbits under the isometries, supports a new sigma model. The target space geometry of the new model is the quotient of the T by the isometry group. This is first described for a bosonic sigma model and it is pointed out that we need to understand supersymmetric sigma models, their isometries and gauging as well as the quotient in order to apply the scheme to models with extended supersymmetry. We then look at these issues. The final goal is to construct new hyperkahler geometries from hyperkähler geometries with isometries, so making sure that the quotient construction preserves the symmetries etc. Ulf Lindstrom is Leverhulme Visiting Professor at Imperial College.
Sigma models are maps from a domain to a target space T. The geometry of the target space is determined by the dimension of the domain and symmetries of the model. When it has isometries that can be gauged, the quotient space, i.e., the space of orbits under the isometries, supports a new sigma model. The target space geometry of the new model is the quotient of the T by the isometry group. This is first described for a bosonic sigma model and it is pointed out that we need to understand supersymmetric sigma models, their isometries and gauging as well as the quotient in order to apply the scheme to models with extended supersymmetry. We then look at these issues. The final goal is to construct new hyperkahler geometries from hyperkähler geometries with isometries, so making sure that the quotient construction preserves the symmetries etc. Ulf Lindstrom is Leverhulme Visiting Professor at Imperial College.
Posted by: CityU2
Tuesday, 23 May 2023
Interacting UV fixed points in QFT and quantum gravity
Daniel Litim
(University of Sussex)
Abstract:
Free or interacting UV fixed points play a key role
in the fundamental definition of QFT. In this talk,
I give a broad overview of weakly and strongly interacting
fixed points in 3d and 4d QFTs including models of particle
physics with or without supersymmetry, and fermionic
theories. Further, I explain methods and ideas to search
for fixed points in 4d quantum gravity. Implications from
the viewpoint of CFTs and higher-spin gauge theories through
the AdS/CFT conjecture are also discussed.
Free or interacting UV fixed points play a key role
in the fundamental definition of QFT. In this talk,
I give a broad overview of weakly and strongly interacting
fixed points in 3d and 4d QFTs including models of particle
physics with or without supersymmetry, and fermionic
theories. Further, I explain methods and ideas to search
for fixed points in 4d quantum gravity. Implications from
the viewpoint of CFTs and higher-spin gauge theories through
the AdS/CFT conjecture are also discussed.
Posted by: IC
Wednesday, 24 May 2023
Machine Learning and Flows for Lattice QCD
📍 London
Sebastien Racaniere
(Deepmind)
Abstract:
Recently, there have been some very impressive advances in generative models for sound, text and images. In this talk, I will look into applications of generative models to Lattice QCD. The models I will consider are flows, which are families of diffeomorphisms transforming simple base distributions into complicated target distributions. Traditional ML flows are on vector spaces, which is different from our setup where we need to deal with products of SU(N). I will give details on how we built these flows, and explain how known symmetries of LQCD can be incorporated into them.
Recently, there have been some very impressive advances in generative models for sound, text and images. In this talk, I will look into applications of generative models to Lattice QCD. The models I will consider are flows, which are families of diffeomorphisms transforming simple base distributions into complicated target distributions. Traditional ML flows are on vector spaces, which is different from our setup where we need to deal with products of SU(N). I will give details on how we built these flows, and explain how known symmetries of LQCD can be incorporated into them.
Posted by: andrea
Integrated correlators in N=4 super Yang-Mills
Congkao Wen
(Queen Mary University of London)
Abstract:
Over the past few years, it has been shown that, when integrating out the spacetime dependence with a certain integration measure, some four-point correlation functions in N=4 super Yang-Mills (SYM) can be computed exactly. These physical observables are often called integrated correlators, which are functions of Yang-Mills coupling \tau, and transform under S-duality of N=4 SYM. In this talk, I will review some of the recent developments regarding these integrated correlators. In particular, I will discuss the so-called Laplace-difference equations that determine the integrated correlators recursively. I will also present the generating functions of the integrated correlators that resum the ranks of the gauge group and the charges of the operators, from which we will further determine the large-N and large-charge properties of the integrated correctors.
Over the past few years, it has been shown that, when integrating out the spacetime dependence with a certain integration measure, some four-point correlation functions in N=4 super Yang-Mills (SYM) can be computed exactly. These physical observables are often called integrated correlators, which are functions of Yang-Mills coupling \tau, and transform under S-duality of N=4 SYM. In this talk, I will review some of the recent developments regarding these integrated correlators. In particular, I will discuss the so-called Laplace-difference equations that determine the integrated correlators recursively. I will also present the generating functions of the integrated correlators that resum the ranks of the gauge group and the charges of the operators, from which we will further determine the large-N and large-charge properties of the integrated correctors.
Posted by: IC2