Marcus Spradlin
(Brown University)
03/07/2017, 12:00
Marcus Spradlin
(Brown University)
03/07/2017, 16:00
Alessandro Georgoudis
(Uppsala University)
03/07/2017, 17:20
For any given Feynman graph, the set of integrals with all possible powers of the propagators spans a vector space of finite dimension. I will introduce the package Azurite (arXiv:1612.04252) which efficiently finds a basis of this vector space. It constructs the needed integration-by-parts (IBP) identities on a set of generalized- unitarity cuts. It is based on syzygy computations and...
Vuong-Viet Tran
(Durham University)
03/07/2017, 17:50
We introduce the "triangle" and "pentagon" rules for obtaining contributing coefficients to the four-point correlation function and scattering amplitude integrands in planar, maximally supersymmetric Yang-Mills theory. Combining these graphical rules with the rung rule prove powerful enough to fully determine both functions through ten loops. We illustrate their applications, compare their...
Marcus Spradlin
(Brown University)
04/07/2017, 12:00
Marcus Spradlin
(Brown University)
04/07/2017, 16:00
Jorrit Bosma
(ETH, Zurich)
04/07/2017, 17:20
After recalling the basics of generalized unitarity and maximal cuts, I will discuss recent work with Mads S{\o}gaard and Yang Zhang (1704.04255):
We discuss a procedure for computing maximal cuts in general D dimensions, based on the Baikov representation which simplifies the structure of the cuts. In our procedure, for a given topology, the integration splits into several regions and the...
Sebastian Mizera
(Perimeter Institute for Theoretical Physics)
04/07/2017, 17:50
We study surprising connections between algebraic topology and string theory amplitudes which underlie Kawai–Lewellen–Tye (KLT) relations. For instance, we show that entries of the inverse KLT kernel can be understood as intersection numbers of certain cycles. In the field-theory limit, combinatorics of these intersections gives rise to the bi-adjoint scalar theory.
John Joseph Carrasco
(CEA, Saclay)
05/07/2017, 09:30
John Joseph Carrasco
(CEA, Saclay)
05/07/2017, 11:00
Jaroslav Trnka
(University of California, Davis)
05/07/2017, 12:00
Jarosalav Trnka
(University of California, Davis)
05/07/2017, 14:30
Gustav Mogull
(University of Edinburgh)
05/07/2017, 17:20
The study of loop-level scattering amplitudes in (super-)Yang-Mills theories has seen enormous progress over the last decade or so.
Unfortunately, many of these developments are limited to the planar limit which consists of only planar Feynman diagrams. Meanwhile, loop-level (super-)gravity amplitudes are difficult to calculate with ordinary Feynman diagrams. In this talk I will introduce...
Chia-Hsien Shen
(Caltech)
05/07/2017, 17:50
The talk is based on 1612.00868 and work to appear with Clifford Cheung and Congkao Wen.
We derive new scattering amplitudes relations which reveal a hidden unity among theories of diverse spins in general spacetime dimensions. These relations are built from a set of Lorentz invariant differential operators which transmute states of higher spin into states of lower spin. Transmutation takes...
John Joseph Carrasco
(CEA, Saclay)
06/07/2017, 12:00
Jaroslav Trnka
(University of California, Davis)
06/07/2017, 14:30
Andrew McLeod
(SLAC, Stanford University)
06/07/2017, 17:20
Bootstrapping techniques---wherein one imposes known constraints on an ansatz in the hope of uniquely determining the answer---have proven to be an increasingly powerful method for computing amplitudes in recent years. While the most significant progress in this direction has been made in planar maximally supersymmetric Yang- Mills theory, these techniques can be naturally extended to the...
Theresa Abl
(ETH, Zurich)
06/07/2017, 17:50
I will discuss scattering amplitudes in strongly coupled N=4 super Yang-Mills theory in the multi-Regge limit. In the strong coupling regime, the calculation of the scattering amplitudes reduces to the solution of a system of non-linear, coupled integral equations through the AdS/CFT-correspondence. These equations reduce to standard Bethe ansatz equations in the multi-Regge limit. In this...
Jaroslav Trnka
(University of California, Davis)
07/07/2017, 09:30
Jaroslav Trnka
(University of California, Davis)
07/07/2017, 11:00
John Joseph Carrasco
(Institute for Theoretical Physics (IPhT), CEA-Saclay and University of Paris-Saclay)
07/07/2017, 12:00
Joe Farrow
(Durham University)
07/07/2017, 17:20
I will discuss how on-shell diagrams for N=4 Super Yang Mills can be extended to N=8 Supergravity, giving Grassmannian integral formulae for tree-level amplitudes.
I will then describe the connection between these formulae and equivalent expressions for the same amplitudes arising from ambitwistor string theory.
Andres Luna-Godoy
(University of Glasgow)
07/07/2017, 17:50
The BCJ double copy relates the scattering amplitudes from gauge and gravity theories. One such theory corresponds to a model first developed by Volkov and Akulov to describe Goldstone fermions (associated with spontaneous supersymmetry breaking). It was later realized that the Volkov-Akulov model is equivalent to the same constrained (nilpotent) superfields appearing in the cosmological...
