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New Constraints on the Amplitude of Cosmic Density Fluctuations and Intracluster Gas from the Thermal SZ Signal Measured by Planck and ACT
November 11, 2013

PIRSA:13110081
Astrophysics
13/14 PSI - Condensed Matter - Lecture 1
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 11, 2013

PIRSA:13110027
13/14 PSI - Quantum Field Theory II - Lecture 1

Francois David CEA Saclay

November 11, 2013

PIRSA:13110008
Discussion

Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics

November 08, 2013

PIRSA:13110079
Twist Defects in Topological Systems with Anyonic Symmetries

Jeffrey Teo University of Illinois Urbana-Champaign

November 08, 2013

PIRSA:13110078
Quantum and Classical Anomalies

Michael Stone University of Illinois Urbana-Champaign

November 08, 2013

PIRSA:13110077
Majorana State Properties in Semiconductor and Oxide Superconducting Quantum Wires

Allan MacDonald The University of Texas at Austin

November 08, 2013

PIRSA:13110076
Discussion

Eduardo Fradkin University of Illinois Urbana-Champaign

November 07, 2013

PIRSA:13110075
Quantum quenches & holography

Robert Myers Perimeter Institute for Theoretical Physics

November 07, 2013

PIRSA:13110074
General Relativity for Cosmology - Lecture 16

Achim Kempf University of Waterloo

November 07, 2013

PIRSA:13110004
Many-body localization: entanglement, emergent conservation laws, and the structure of eigenstates

Dmitry Abanin Princeton University

November 07, 2013

PIRSA:13110073
Matter matters in asymptotically safe quantum gravity
November 07, 2013

PIRSA:13110048
General Relativity & Quantum Cosmology

New Constraints on the Amplitude of Cosmic Density Fluctuations and Intracluster Gas from the Thermal SZ Signal Measured by Planck and ACT
November 11, 2013

PIRSA:13110081
Astrophysics
Galaxy clusters form from the rarest peaks in the initial matter distribution, and hence are a sensitive probe of the amplitude of density fluctuations (sigma_8), the amount of matter in the universe, and the growth rate of structure. Galaxy clusters have the potential to constrain dark energy and neutrino masses. However, cluster cosmology is currently limited by systematic uncertainties due to poorly understood intracluster gas physics. I will present new statistical approaches to understand clusters and improve their cosmological constraining power through the thermal Sunyaev-Zel'dovich (tSZ) effect. First, I will describe a forthcoming first detection of the cross-correlation of the tSZ signal reconstructed from Planck data with the large-scale matter distribution traced by the Planck CMB lensing potential. This statistic measures the amount of hot gas found in moderately massive groups and clusters (M ~ 10^13-10^14.5 M_sun), a mass scale below that probed by direct cluster detections. Second, I will describe the first measurement of the PDF of the tSZ field using ACT 148 GHz maps. This measurement contains information from all (zero-lag) moments of the tSZ field, beyond simply the 2- or 3-point functions. It is a very sensitive probe of sigma_8 and may also provide a method with which to break the degeneracy between sigma_8 and uncertainties in the physics of the intracluster gas.
13/14 PSI - Condensed Matter - Lecture 1
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 11, 2013

PIRSA:13110027
13/14 PSI - Quantum Field Theory II - Lecture 1

Francois David CEA Saclay

November 11, 2013

PIRSA:13110008
Discussion

Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics

November 08, 2013

PIRSA:13110079
Twist Defects in Topological Systems with Anyonic Symmetries

Jeffrey Teo University of Illinois Urbana-Champaign

November 08, 2013

PIRSA:13110078

Twist defects are point-like objects that support robust non-local storage of quantum information and non-abelian unitary operations. Unlike quantum deconfined anyonic excitations, they rely on symmetry rather than a non-abelian topological order. Zero energy Majorana bound states can arise at lattice defects, such as disclinations and dislocations, in a topological crystalline superconductor. More general parafermion bound state can appear as twist defects in a topological phase with an anyonic symmetry, such as a bilayer fractional quantum Hall state and the Kitaev toric code. They are however fundamentally different from quantum anyonic excitations in a true topological phase. This is demonstrated by their unconventional exchange and braiding behavior, which is characterized by a modified spin statistics theorem and modular invariance.
Quantum and Classical Anomalies

Michael Stone University of Illinois Urbana-Champaign

November 08, 2013

PIRSA:13110077

I will begin reviewing the Callan-Harvey mechanism of anomaly inflow with particular focus on topological edge states and show how the inflow picture naturally converts the non-covariant "consistent" gauge anomaly of Bardeen and Zumino to the more physical "covariant" anomaly. I will then discuss some recent derivations of the covariant form of the gauge anomaly from classical phase space flows.
Majorana State Properties in Semiconductor and Oxide Superconducting Quantum Wires

Allan MacDonald The University of Texas at Austin

November 08, 2013

PIRSA:13110076

When proximity coupled to s-wave superconductors, quantum wires can support effective p-wave superconductivity under appropriate circumstances. The p-wave state has Majorana states at the wire ends which can store quantum information. I will discuss some properties of Majorana states formed in oxide and semiconductor quantum wires, including superconducting state phase diagrams as a function of spin-orbit coupling strength, Fermi energy, and external magnetic field strength, and Majorana exchange properties.
Discussion

Eduardo Fradkin University of Illinois Urbana-Champaign

November 07, 2013

PIRSA:13110075
Quantum quenches & holography

Robert Myers Perimeter Institute for Theoretical Physics

November 07, 2013

PIRSA:13110074

We employ holographic techniques to study quantum quenches at finite temperature, where the quenches involve varying the coupling of the boundary theory to a relevant operator with an arbitrary conformal dimension. The evolution of the system is studied by evaluating the expectation value of the quenched operator and the stress tensor throughout the process. The time dependence of the new coupling is characterized by a fixed timescale and the response of the observables depends on the ratio of the this timescale to the initial temperature. The observables exhibit universal scaling behaviours when the transitions are either fast or slow, i.e., when this ratio is very small or very large. For fast quenches, we uncover a universal scaling behaviour in the response of the system, which depends only on the conformal dimension of the quenched operator in the vicinity of the ultraviolet fixed point of the theory.
General Relativity for Cosmology - Lecture 16

Achim Kempf University of Waterloo

November 07, 2013

PIRSA:13110004
Many-body localization: entanglement, emergent conservation laws, and the structure of eigenstates

Dmitry Abanin Princeton University

November 07, 2013

PIRSA:13110073
Matter matters in asymptotically safe quantum gravity
November 07, 2013

PIRSA:13110048
General Relativity & Quantum Cosmology
The Functional Renormalisation Group technique has received great attention in recent times proving itself as a powerful tool to describe the high energy behaviour of gravitational interactions.
Its key ingredient is a nontrivial fixed point of the theory renormalization group flow which controls the behavior of the coupling constants in the ultraviolet regime and ensures that physical quantities are safe from divergences. I will briefly review the main ingredients of the gravitational asymptotic safety framework before focusing on the effect of massless minimally coupled scalars, fermions and vector fields on the gravitational fixed point. I will then set bounds on the type and number of such fields requiring the existence of a UV attractive fixed point. I will also discuss the dynamically generated quantum-gravity scale in asymptotic safety, which is the transition scale to the fixed-point regime, and its variation as a function of matter degrees of freedom. To conclude I will also consider the case of higher dimensional models.

Title	Date	Collection	Type	Info
New Constraints on the Amplitude of Cosmic Density Fluctuations and Intracluster Gas from the Thermal SZ Signal Measured by Planck and ACT	2013‑11‑11	Cosmology and Gravitation	Scientific Series	View details
13/14 PSI - Condensed Matter - Lecture 1	2013‑11‑11	13/14 PSI - Condensed Matter	Course	View details
13/14 PSI - Quantum Field Theory II - Lecture 1	2013‑11‑11	13/14 PSI - Quantum Field Theory II	Course	View details
Discussion	2013‑11‑08	PI-UIUC 2013	Conference	View details
Twist Defects in Topological Systems with Anyonic Symmetries	2013‑11‑08	PI-UIUC 2013	Conference	View details
Quantum and Classical Anomalies	2013‑11‑08	PI-UIUC 2013	Conference	View details
Majorana State Properties in Semiconductor and Oxide Superconducting Quantum Wires	2013‑11‑08	PI-UIUC 2013	Conference	View details
Discussion	2013‑11‑07	PI-UIUC 2013	Conference	View details
Quantum quenches & holography	2013‑11‑07	PI-UIUC 2013	Conference	View details
General Relativity for Cosmology - Lecture 16	2013‑11‑07	General Relativity for Cosmology - 2013	Course	View details
Many-body localization: entanglement, emergent conservation laws, and the structure of eigenstates	2013‑11‑07	PI-UIUC 2013	Conference	View details
Matter matters in asymptotically safe quantum gravity	2013‑11‑07	Quantum Gravity	Scientific Series	View details

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Format results

New Constraints on the Amplitude of Cosmic Density Fluctuations and Intracluster Gas from the Thermal SZ Signal Measured by Planck and ACT

13/14 PSI - Condensed Matter - Lecture 1

13/14 PSI - Quantum Field Theory II - Lecture 1

Discussion

Twist Defects in Topological Systems with Anyonic Symmetries

Quantum and Classical Anomalies

Majorana State Properties in Semiconductor and Oxide Superconducting Quantum Wires

Discussion

Quantum quenches & holography

General Relativity for Cosmology - Lecture 16

Many-body localization: entanglement, emergent conservation laws, and the structure of eigenstates

Matter matters in asymptotically safe quantum gravity

New Constraints on the Amplitude of Cosmic Density Fluctuations and Intracluster Gas from the Thermal SZ Signal Measured by Planck and ACT

13/14 PSI - Condensed Matter - Lecture 1

13/14 PSI - Quantum Field Theory II - Lecture 1

Discussion

Twist Defects in Topological Systems with Anyonic Symmetries

Quantum and Classical Anomalies

Majorana State Properties in Semiconductor and Oxide Superconducting Quantum Wires

Discussion

Quantum quenches & holography

General Relativity for Cosmology - Lecture 16

Many-body localization: entanglement, emergent conservation laws, and the structure of eigenstates

Matter matters in asymptotically safe quantum gravity