Triangle Seminars
Tuesday, 12 Mar 2024
Lonti: Gravity as an Effective Field Theory (3/4)
Claudia de Rham
(Imperial College)
Abstract:
CANCELLED due to an unforeseen speaker emergency.
CANCELLED due to an unforeseen speaker emergency.
Posted by: CityU2
MTC(M3,G): 3d Topological Order Labeled by Seifert Manifolds
📍 London
Jingxiang Wu
(Oxford)
Abstract:
We propose a correspondence between topological order in 2+1d and
Seifert three-manifolds together with a choice of ADE gauge group G.
Topological order in 2+1d is known to be characterised in terms of
modular tensor categories (MTCs), and we thus propose a relation
between MTCs and Seifert three-manifolds. The correspondence defines
for every Seifert manifold and choice of G a fusion category, which we
conjecture to be modular whenever the Seifert manifold has trivial
first homology group with coefficients in the centre of G. The
construction determines the spins of anyons and their S-matrix, and
provides a constructive way to determine the R- and F-symbols from
simple building blocks. We explore the possibility that this
correspondence provides an alternative classification of MTCs, which
is put to the test by realising all MTCs (unitary or non-unitary) with
rank r<=5 in terms of Seifert manifolds and a choice of Lie group G.
We propose a correspondence between topological order in 2+1d and
Seifert three-manifolds together with a choice of ADE gauge group G.
Topological order in 2+1d is known to be characterised in terms of
modular tensor categories (MTCs), and we thus propose a relation
between MTCs and Seifert three-manifolds. The correspondence defines
for every Seifert manifold and choice of G a fusion category, which we
conjecture to be modular whenever the Seifert manifold has trivial
first homology group with coefficients in the centre of G. The
construction determines the spins of anyons and their S-matrix, and
provides a constructive way to determine the R- and F-symbols from
simple building blocks. We explore the possibility that this
correspondence provides an alternative classification of MTCs, which
is put to the test by realising all MTCs (unitary or non-unitary) with
rank r<=5 in terms of Seifert manifolds and a choice of Lie group G.
Posted by: QMW
Wednesday, 13 Mar 2024
The view of a point: Wigner-Inonu contractions and the flat space limit of AdS scattering
📍 London
David Berenstein
(UCSB)
Abstract:
I will describe how to consider the flat space limit of scaterig in AdS relative to a point (where sacttering occurs). The kinematics is related to the Wigner-Inonu contraction. In particular, I will discuss how to take the proper limits of wave functions in AdS (times extra dimensions) to understand a notion of in states and out states and how a scattering amplitude should be conceived. This will make use of the embedding formalism, where the description of these wave functions is simple. I will show how these wave functions are related to other constructions in AdS/CFT and suggest how the Mellin parameters of these other setups arise from integral representations of the wave functions in terms of Schwinger parameters.
I will describe how to consider the flat space limit of scaterig in AdS relative to a point (where sacttering occurs). The kinematics is related to the Wigner-Inonu contraction. In particular, I will discuss how to take the proper limits of wave functions in AdS (times extra dimensions) to understand a notion of in states and out states and how a scattering amplitude should be conceived. This will make use of the embedding formalism, where the description of these wave functions is simple. I will show how these wave functions are related to other constructions in AdS/CFT and suggest how the Mellin parameters of these other setups arise from integral representations of the wave functions in terms of Schwinger parameters.
Posted by: QMW
Vertex algebras in SUSY QFT across dimensions
📍 London
Mykola Dedushenko
(Simons Center for Geometry and Physics)
Abstract:
I will describe a construction relating the Vertex Operator Algebra (VOA) of a 4d N=2 superconformal field theory (SCFT) to the boundary VOA in 3d N=4 QFT, and to the VOA in 2d QFT. Besides unifying several known constructions, this also draws connections to many other interesting problems, among which are the novel rank-zero 3d N=4 SCFTs emerging in the high-temperature limit of a 4d SCFT "on the second sheet".
I will describe a construction relating the Vertex Operator Algebra (VOA) of a 4d N=2 superconformal field theory (SCFT) to the boundary VOA in 3d N=4 QFT, and to the VOA in 2d QFT. Besides unifying several known constructions, this also draws connections to many other interesting problems, among which are the novel rank-zero 3d N=4 SCFTs emerging in the high-temperature limit of a 4d SCFT "on the second sheet".
Posted by: QMW