High Energy Physics

Displaying 1597 - 1608 of 3012

Classical Space Times from S Matrices

Ira Rothstein Carnegie Mellon University
November 26, 2013

PIRSA:13110053
High Energy Physics
New Light Species and the CMB - Joint Cosmology/Particle Physics Seminar

Christopher Brust
November 19, 2013

PIRSA:13110051
High Energy Physics
Spin and Long-Range Forces: The Unfinished Tale of the Last Massless Particle

Natalia Toro Stanford University
November 13, 2013

PIRSA:13110047
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
Baryogenesis from WIMPs
November 12, 2013

PIRSA:13110046
High Energy Physics
From the symmetric group to giant gravitons in super Yang-Mills theory
November 05, 2013

PIRSA:13110084
High Energy Physics
Induced Electroweak Symmetry Breaking and Supersymmetry

Jamison Galloway New York University (NYU)
November 05, 2013

PIRSA:13110050
High Energy Physics
Split Dirac Supersymmetry and a Higgsino LSP
November 01, 2013

PIRSA:13110052
High Energy Physics
Gravity and the Search for New Physics with Cosmology

Kris Sigurdson University of British Columbia
October 30, 2013

PIRSA:13100098
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
Minimal Distances and the RG Flow
October 29, 2013

PIRSA:13100069
High Energy Physics
Heavy particle effective field theory: formalism, dark matter and the proton size puzzle

Richard Hill University of Kentucky
October 18, 2013

PIRSA:13100107
High Energy Physics

Classical Space Times from S Matrices

Ira Rothstein Carnegie Mellon University
November 26, 2013

PIRSA:13110053
High Energy Physics
Progress in calculating S matrix elements have shown that the malicious redundancies in non-linear gauge theories can be circumvented by utilizing unitarity methods in conjunction with BCFW recursion relations. When calculating in this fashion all of the interaction vertices beyond the three point function can be ignored. This simplification is especially useful in gravity which contains an infinite number of such non-linear interactions. It is natural to ask whether off-shell quantities, such as classical solutions, can also be generated using only the three point vertex. In this talk I will show that this is indeed the case by extracting classical solutions to GR from on-hell two to two scattering S-matrix elements. In so doing we will completely circumvent the action as well as the equations of motion. The only inputs will be Lorentz invariance, the existence of a massless spin-two particle and locality. Because of the double copy relation this implies there exists, a yet to be understood, connection between solutions to Yang-Mills theory and Gravity. I will also discuss how this technique can be used to simplify calculations of higher order post-Newtonian corrections to gravitational potentials relevant to the problem of binary inspirals.
New Light Species and the CMB - Joint Cosmology/Particle Physics Seminar

Christopher Brust
November 19, 2013

PIRSA:13110051
High Energy Physics
The effective number of neutrino species in our universe, Neff, is capable of probing the presence of new light or massless species in our universe. I will first review relevant facts about both CMB measurements of new light species and thermodynamics in the early universe. Then, I will present the effects of many models of BSM physics containing new light species on the CMB, including models containing eV-scale sterile neutrinos compatible with anomalies in neutrino experiments, and interpret the compatibility of the parameter space of these models in terms of the recent results from the Planck satellite. I will argue that the bounds on couplings obtained from the Planck measurement of the CMB are competitive with bounds coming from other areas of physics.
Spin and Long-Range Forces: The Unfinished Tale of the Last Massless Particle

Natalia Toro Stanford University
November 13, 2013

PIRSA:13110047
High Energy Physics
The success of gauge theory descriptions of Nature follows simply, in hindsight, from Lorentz symmetry, quantum mechanics, and the existence of interacting massless particles with spin. Yet, remarkably, the most generic type of massless particle spin has never been seriously examined: Wigner's so-called "continuous spin" particles (CSPs), which have a tower of polarization states carrying all integer or half-integer helicities that mix under boosts. I will explain recent progress in understanding these particles on two fronts: simple scattering amplitudes and a free quantum field theory. The scattering amplitudes give two remarkable insights into CSP physics. First, Lorentz symmetry protects CSP interactions from the dysfunction one might expect in a theory with infinitely many polarization states: divergent cross-sections and problematic thermodynamics. Second, and most intriguingly, CSP interactions approach those of ordinary scalars or helicity-1 or 2 gauge bosons in a high-energy "correspondence" regime. While a full interacting theory of CSPs remains elusive, these results suggest that any such theory would extend Maxwell electrodynamics and/or general relativity in a viable and testable way.
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.
Baryogenesis from WIMPs
November 12, 2013

PIRSA:13110046
High Energy Physics
We propose a robust, unified framework, in which the similar baryon and dark matter cosmic abundances both arise from the physics of weakly interacting massive particles (WIMPs), with the rough quantitative success of the so-called “WIMP miracle”. In particular the baryon asymmetry arises from the decay of a meta-stable WIMP after its thermal freezeout at or below the weak scale. A minimal model and its embedding in R-parity violating (RPV) natural SUSY are studied as examples. The new mechanism saves RPV SUSY from the potential crisis of washing out primordial baryon asymmetry. We also consider the embedding of this idea in RPV split SUSY, where the mechanism works within the minimal model, and independently motivates the mini-split scale. Phenomenological implications for the LHC and precision tests are discussed.
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.
Induced Electroweak Symmetry Breaking and Supersymmetry

Jamison Galloway New York University (NYU)
November 05, 2013

PIRSA:13110050
High Energy Physics
I'll discuss a class of supersymmetric models in which the physical Higgs mass is freed from the quartic coupling, thereby allowing for a 125 GeV Higgs state whose self-interaction can be much smaller than in the SM via a mechanism of 'induced EWSB'. This class of models provides a unique alternative to other realizations of natural SUSY, and the simplest realizations necessitate additional characteristic scalars below the TeV scale, thus altering phenomenological predictions for additional Higgses at the LHC.
Split Dirac Supersymmetry and a Higgsino LSP
November 01, 2013

PIRSA:13110052
High Energy Physics
TBA
Gravity and the Search for New Physics with Cosmology

Kris Sigurdson University of British Columbia
October 30, 2013

PIRSA:13100098
High Energy Physics
Despite its feeble in strength, gravity plays a pivotal role in shaping our Universe and the things in it. Ever since Newton formulated his universal law of gravitation the recognition that all things gravitate has been nearly sacrosanct. Repeatedly, apparent gravitational anomalies have either foretold the existence of new physics or a misunderstanding of gravity itself, from the existence of nuclear forces to Einstein's general relativity. Eighty years ago gravity betrayed the existence of dark matter, and fifteen years ago gravity demanded dark energy from reluctant cosmologists. I will discuss how gravity enables modern cosmology to explore the echoes of the invisible universe, even if it is impossible or difficult to directly see the invisible universe. In particular, I will show how gravity enables us to put surprisingly severe constraints on the coupling of dark matter to new light particles and search for secret interactions between Fermi's elusive neutrinos. The physics and cosmic history of the invisible universe are writ large across the cosmos itself, and gravity is our tried and trusted messenger.
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.
Minimal Distances and the RG Flow
October 29, 2013

PIRSA:13100069
High Energy Physics
We will discuss the renormalization group flow between different classes of CFTs in four dimensions and study possible lower bounds on the "distances" between these theories.
Heavy particle effective field theory: formalism, dark matter and the proton size puzzle

Richard Hill University of Kentucky
October 18, 2013

PIRSA:13100107
High Energy Physics
Heavy particle expansions, familiar from heavy quark physics, have found important applications in the analysis of dark matter candidates and their interactions with the Standard Model. From a different direction, precision spectroscopy of muonic hydrogen has challenged QED and required more precise knowledge of proton structure. These problems have forced a closer examination of the construction of general heavy particle lagrangians at high orders in the 1/M expansion, and in the absence of known ultraviolet completions. Key aspects of this formalism, including the emergence of Lorentz invariance from "nonrelativistic" lagrangians, are reviewed, and several applications are presented. A status report on the proton radius puzzle is given.

Title	Speaker(s)	Date	Talk Type	Info link
Classical Space Times from S Matrices	Ira Rothstein	2013-11-26	Scientific Series	View details
New Light Species and the CMB - Joint Cosmology/Particle Physics Seminar	Christopher Brust	2013-11-19	Scientific Series	View details
Spin and Long-Range Forces: The Unfinished Tale of the Last Massless Particle	Natalia Toro	2013-11-13	Scientific Series	View details
On Scale and Conformal Invariance in Four Dimensions	Anatoly Dymarsky	2013-11-12	Scientific Series	View details
Baryogenesis from WIMPs		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
Induced Electroweak Symmetry Breaking and Supersymmetry	Jamison Galloway	2013-11-05	Scientific Series	View details
Split Dirac Supersymmetry and a Higgsino LSP		2013-11-01	Scientific Series	View details
Gravity and the Search for New Physics with Cosmology	Kris Sigurdson	2013-10-30	Scientific Series	View details
The Geometry of Supersymmetric Partition Functions	Guido Festuccia	2013-10-29	Scientific Series	View details
Minimal Distances and the RG Flow		2013-10-29	Scientific Series	View details
Heavy particle effective field theory: formalism, dark matter and the proton size puzzle	Richard Hill	2013-10-18	Scientific Series	View details

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Format results

Classical Space Times from S Matrices

New Light Species and the CMB - Joint Cosmology/Particle Physics Seminar

Spin and Long-Range Forces: The Unfinished Tale of the Last Massless Particle

On Scale and Conformal Invariance in Four Dimensions

Baryogenesis from WIMPs

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

Induced Electroweak Symmetry Breaking and Supersymmetry

Split Dirac Supersymmetry and a Higgsino LSP

Gravity and the Search for New Physics with Cosmology

The Geometry of Supersymmetric Partition Functions

Minimal Distances and the RG Flow

Heavy particle effective field theory: formalism, dark matter and the proton size puzzle

Classical Space Times from S Matrices

New Light Species and the CMB - Joint Cosmology/Particle Physics Seminar

Spin and Long-Range Forces: The Unfinished Tale of the Last Massless Particle

On Scale and Conformal Invariance in Four Dimensions

Baryogenesis from WIMPs

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

Induced Electroweak Symmetry Breaking and Supersymmetry

Split Dirac Supersymmetry and a Higgsino LSP

Gravity and the Search for New Physics with Cosmology

The Geometry of Supersymmetric Partition Functions

Minimal Distances and the RG Flow

Heavy particle effective field theory: formalism, dark matter and the proton size puzzle