Quantum Fields and Strings

725 talks

S003

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Displaying 397 - 408 of 725

Cluster Polylogarithms for Scattering Amplitudes
February 18, 2014

PIRSA:14020147
High Energy Physics
Towards a 1/c Expansion in 2d Conformal Field Theory
February 04, 2014

PIRSA:14020084
High Energy Physics
Mayer-Cluster Expansion of Instanton Partition Functions and Thermodynamic Bethe Ansatz

Carlo Meneghelli University of Oxford
January 28, 2014

PIRSA:14010096
High Energy Physics
Boundaries and Defects in 4d N=4 SYM

Masahito Yamazaki University of Tokyo
January 21, 2014

PIRSA:14010086
High Energy Physics
(0,4) sigma models and K3

Sarah Harrison Stanford University
December 18, 2013

PIRSA:13120071
High Energy Physics
Integrability (and Near Integrability) in Matrix-valued Field Theories

Axel Cortes Cubero City University of New York (CUNY) - Department of Physics
December 13, 2013

PIRSA:13120068
High Energy Physics
(0,2) Trialities

Abhijit Gadde Stony Brook University
December 10, 2013

PIRSA:13120062
High Energy Physics
On Scale and Conformal Invariance in Four Dimensions

Anatoly Dymarsky Skolkovo Institute of Science and Technology
November 12, 2013

PIRSA:13110068
High Energy Physics
From the symmetric group to giant gravitons in super Yang-Mills theory
November 05, 2013

PIRSA:13110084
High Energy Physics
The Geometry of Supersymmetric Partition Functions

Guido Festuccia Institute for Advanced Study (IAS) - School of Mathematics
October 29, 2013

PIRSA:13100130
High Energy Physics
All AdS7 solutions of type II supergravity

Alessandro Tomasiello University of Milano-Bicocca
October 18, 2013

PIRSA:13100108
High Energy Physics
Vector Beta Function

Yu Nakayama University of California, Berkeley
October 17, 2013

PIRSA:13100082
High Energy Physics

Cluster Polylogarithms for Scattering Amplitudes
February 18, 2014

PIRSA:14020147
High Energy Physics
Motivated by the cluster structure of two-loop scattering amplitudes in N = 4 Yang-Mills theory we define cluster polylogarithm functions. We find that all such functions of weight 4 are made up of a single simple building block associated to the A2 cluster algebra. Adding the requirement of locality on generalized Stasheff polytopes, we find that these A2 building blocks arrange themselves to form a unique function associated to the A3 cluster algebra. ThisA3 function manifests all of the cluster algebraic structure of the two-loop n-particle MHV amplitudes for all n, and we use it to provide an explicit representation for the most complicated part of the n = 7 amplitude as an example.
Towards a 1/c Expansion in 2d Conformal Field Theory
February 04, 2014

PIRSA:14020084
High Energy Physics
I will describe progress in deriving 3d gravity directly from 2d conformal field theory at large central charge 'c'. In a large class of CFTs, using general arguments like modular invariance, crossing symmetry, and the OPE expansion, the spectrum, the entanglement entropy, and certain partition functions can be computed to leading order in a 1/c expansion. The results agree with universal features of 3d gravity required by black hole thermodynamics and the Ryu-Takayanagi formula; furthermore, the relevant 3d geometries appear automatically from CFT calculations in this regime.
Mayer-Cluster Expansion of Instanton Partition Functions and Thermodynamic Bethe Ansatz

Carlo Meneghelli University of Oxford
January 28, 2014

PIRSA:14010096
High Energy Physics
In arXiv:0908.4052, Nekrasov and Shatashvili pointed out that the N=2 instanton partition function in a special limit of the Omega-deformation parameters is characterized by certain thermodynamic Bethe ansatz (TBA) like equations.In this talk I will present an explicit derivation of this fact as well as generalizations to quiver gauge theories. The TBA equations derived entirely within gauge theory have been proposed to encode the spectrum of a large class of quantum integrable systems. I will conclude with some remarks on this correspondence.
Boundaries and Defects in 4d N=4 SYM

Masahito Yamazaki University of Tokyo
January 21, 2014

PIRSA:14010086
High Energy Physics
We discuss boundary conditions and domain walls in 4d N=4 SYM, focusing on those preserving 4 supercharges. Along the way we revisit the old problem of the quantum-corrected moduli space of 3d N=2 theories.
(0,4) sigma models and K3

Sarah Harrison Stanford University
December 18, 2013

PIRSA:13120071
High Energy Physics
TBA
Integrability (and Near Integrability) in Matrix-valued Field Theories

Axel Cortes Cubero City University of New York (CUNY) - Department of Physics
December 13, 2013

PIRSA:13120068
High Energy Physics
The principal chiral sigma model (PCSM) in 1+1 dimensions is asymptotically free and has as SU(N)-valued field with massive excitations. We have found all the exact form factors and two-point function of the Noether-current operators at large N using the integrable bootstrap program. At finite N, only the first non-trivial form factors are found, which give a good long distance approximation for the two-point function. We show how to use these new exact results to study non-integrable deformations. One example is the PCSM coupled to a Yang-Mills field. One can approximate the spectrum of the meson-like bound states using our form factors. We also examine an anisotropic version of (2+1)-dimensional Yang-Mills theory, which can be interpreted as an array of coupled PCSM’s.
(0,2) Trialities

Abhijit Gadde Stony Brook University
December 10, 2013

PIRSA:13120062
High Energy Physics
Motivated by the connection between 4-manifolds and 2d N=(0,2) theories, we study the dynamics of a fairly large class of 2d N=(0,2) gauge theories. We see that physics of such theories is very rich, much as the physics of 4d N=1 theories. We discover a new type of duality that is very reminiscent of the 4d Seiberg duality. Surprisingly, the new 2d duality is an operation of order three. We study the low energy physics and use elliptic genus to detect dynamical supersymmetry breaking.
On Scale and Conformal Invariance in Four Dimensions

Anatoly Dymarsky Skolkovo Institute of Science and Technology
November 12, 2013

PIRSA:13110068
High Energy Physics
I will be discussing relation between scale and conformal symmetry in unitary Lorentz invariant QFTs in four dimensions.
From the symmetric group to giant gravitons in super Yang-Mills theory
November 05, 2013

PIRSA:13110084
High Energy Physics
In this talk we will discuss how giant gravitons and their open string interactions emerge from super Yang-Mills Theory. This is accomplished by diagonalizing the one loop dilatation operator on a class of operators with bare dimension of order N. From the result of this diagonalization, the Gauss Law governing the allowed open string excitations of giant gravitons is clearly visible. In addition, we show that this sector of the theory is integrable.
The Geometry of Supersymmetric Partition Functions

Guido Festuccia Institute for Advanced Study (IAS) - School of Mathematics
October 29, 2013

PIRSA:13100130
High Energy Physics
Three-dimensional N=2 theories with a U(1)_R symmetry, can be placed on a compact three manifold M preserving some supersymmetry if and only if M admits a transversely holomorphic foliation (THF). I will show that the partition function of the resulting theory is independent of the metric and depends holomorphically on the moduli of the THF. When applied to supersymmetric field theories on manifolds diffeomorphic to S^3 and S^2 x S^1, this result explains many of the properties observed in explicit determinations of their partition functions.
All AdS7 solutions of type II supergravity

Alessandro Tomasiello University of Milano-Bicocca
October 18, 2013

PIRSA:13100108
High Energy Physics
In M-theory, the only AdS7 supersymmetric solutions are AdS7 × S4 and its orbifolds. In this talk, I will describe a classification of AdS7 supersymmetric solutions in type II supergravity. While in IIB none exist, in IIA with Romans mass (which does not lift to M-theory) there are many new ones. The classification starts from a pure spinor approach reminiscent of generalized complex geometry. Without the need for any Ansatz, the method determines uniquely the form of the metric and fluxes, up to solving a system of ODEs. Namely, the metric on M3 is that of an S2 fibered over an interval; this is consistent with the Sp(1) R-symmetry of the holographically dual (1,0) theory. One can obtain numerically many solutions, with D8 and/or D6 brane sources; topologically, the internal manifold M3 = S^3.
Vector Beta Function

Yu Nakayama University of California, Berkeley
October 17, 2013

PIRSA:13100082
High Energy Physics
We propose various properties of renormalization group beta functions for vector operators in relativistic quantum field theories. We argue that they must satisfy compensated gauge invariance, orthogonality with respect to scalar beta functions, Higgs-like relation among anomalous dimensions and a gradient property. We further conjecture that non-renormalization holds if and only if the vector operator is conserved. The local renormalization group analysis guarantees the first three within power counting renormalization. We verify all the conjectures in conformal perturbation theories and holography in the weakly coupled gravity regime.

Title	Speaker(s)	Date	Talk Type	Info
Cluster Polylogarithms for Scattering Amplitudes		2014-02-18	Scientific Series	View details
Towards a 1/c Expansion in 2d Conformal Field Theory		2014-02-04	Scientific Series	View details
Mayer-Cluster Expansion of Instanton Partition Functions and Thermodynamic Bethe Ansatz	Carlo Meneghelli	2014-01-28	Scientific Series	View details
Boundaries and Defects in 4d N=4 SYM	Masahito Yamazaki	2014-01-21	Scientific Series	View details
(0,4) sigma models and K3	Sarah Harrison	2013-12-18	Scientific Series	View details
Integrability (and Near Integrability) in Matrix-valued Field Theories	Axel Cortes Cubero	2013-12-13	Scientific Series	View details
(0,2) Trialities	Abhijit Gadde	2013-12-10	Scientific Series	View details
On Scale and Conformal Invariance in Four Dimensions	Anatoly Dymarsky	2013-11-12	Scientific Series	View details
From the symmetric group to giant gravitons in super Yang-Mills theory		2013-11-05	Scientific Series	View details
The Geometry of Supersymmetric Partition Functions	Guido Festuccia	2013-10-29	Scientific Series	View details
All AdS7 solutions of type II supergravity	Alessandro Tomasiello	2013-10-18	Scientific Series	View details
Vector Beta Function	Yu Nakayama	2013-10-17	Scientific Series	View details

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Quantum Fields and Strings

Format results

Cluster Polylogarithms for Scattering Amplitudes

Towards a 1/c Expansion in 2d Conformal Field Theory

Mayer-Cluster Expansion of Instanton Partition Functions and Thermodynamic Bethe Ansatz

Boundaries and Defects in 4d N=4 SYM

(0,4) sigma models and K3

Integrability (and Near Integrability) in Matrix-valued Field Theories

(0,2) Trialities

On Scale and Conformal Invariance in Four Dimensions

From the symmetric group to giant gravitons in super Yang-Mills theory

The Geometry of Supersymmetric Partition Functions

All AdS7 solutions of type II supergravity

Vector Beta Function

Cluster Polylogarithms for Scattering Amplitudes

Towards a 1/c Expansion in 2d Conformal Field Theory

Mayer-Cluster Expansion of Instanton Partition Functions and Thermodynamic Bethe Ansatz

Boundaries and Defects in 4d N=4 SYM

(0,4) sigma models and K3

Integrability (and Near Integrability) in Matrix-valued Field Theories

(0,2) Trialities

On Scale and Conformal Invariance in Four Dimensions

From the symmetric group to giant gravitons in super Yang-Mills theory

The Geometry of Supersymmetric Partition Functions

All AdS7 solutions of type II supergravity

Vector Beta Function