Talks

14497 - 14508 of 22691 Results

13/14 PSI - Cosmology Review - Lecture 13

Latham Boyle University of Edinburgh

February 14, 2014

PIRSA:14020102
Low Spin State Mott Insulators and Emergence of novel Quantum Spin Liquids

Baskaran Ganapathy Institute of Mathematical Sciences

February 14, 2014

PIRSA:14020128
13/14 PSI - String Theory Review - Lecture 14

Davide Gaiotto Perimeter Institute for Theoretical Physics

February 14, 2014

PIRSA:14020034
A unification of symmetric Z2 spin liquids on kagome lattice

Yuan-Ming Lu

February 14, 2014

PIRSA:14020118
Introduction to Effective Field Theories - Lecture 11

Cliff Burgess McMaster University

February 14, 2014

PIRSA:14020089
How universal is the entanglement spectrum?

Anushya Chandran Perimeter Institute for Theoretical Physics

February 14, 2014

PIRSA:14020132
13/14 PSI - Condensed Matter Review - Lecture 14

Alioscia Hamma University of Naples Federico II

February 14, 2014

PIRSA:14020107
Challenges in Mathematical Ecology 3: Infectious diseases

Simon Levin

February 13, 2014

SAIFR:7

Physics
Introduction to Quantum Field Theory for Cosmology - Lecture 12

Achim Kempf University of Waterloo

February 13, 2014

PIRSA:14020005
Introduction to Quantum Field Theory for Cosmology - Lecture 11

Achim Kempf University of Waterloo

February 13, 2014

PIRSA:14020001
Probabilistic protocols in quantum information

Joshua Combes University of Colorado Boulder

February 13, 2014

PIRSA:14020138

Quantum Physics
Firewall evasion by quantum gravity

Ted Jacobson University of Maryland, College Park

February 13, 2014

PIRSA:14020136

General Relativity & Quantum Cosmology

13/14 PSI - Cosmology Review - Lecture 13

Latham Boyle University of Edinburgh

February 14, 2014

PIRSA:14020102
Low Spin State Mott Insulators and Emergence of novel Quantum Spin Liquids

Baskaran Ganapathy Institute of Mathematical Sciences

February 14, 2014

PIRSA:14020128

In a conventional Mott insulator, magnitude of local spin moments remain fixed. They are `fixed spin Mott insulators'. We suggest that, in a multi orbital Hubbard model, when local Hund coupling is won over by inter-orbital superexchange couplings between neighboring sites, local spin moment can decrease its value in a cooperative fashion, through a first order phase transition, These are `Low spin state Mott insulators' (LSSMI). The minimal value of spins that can be reached are zero (half), for even (odd) number of electrons per site, We show that in LSSMI, depending on orbital degeneracy and electron number per site, novel quantum spin liquids can emerge, We discuss systems such as Fe arsenide, Fe selenide family and La2CoO3 in the light of our proposal. Certain long standing puzzles, including absence of any magnetic phase transition in La2CoO3 is explained in terms of a novel quantum spin liquid. Some properties of this spin liquid, a liquid of `quantum strings' will be discussed and some predictions made.
13/14 PSI - String Theory Review - Lecture 14

Davide Gaiotto Perimeter Institute for Theoretical Physics

February 14, 2014

PIRSA:14020034
A unification of symmetric Z2 spin liquids on kagome lattice

Yuan-Ming Lu

February 14, 2014

PIRSA:14020118

While there is mounting numerical evidence for a gapped Z2 spin liquid in the kagome Heisenberg model, a complete characterization of this topological phase remains to be accomplished. A defining property, the projective symmetry group (PSG) which fixes how the emergent excitations of the spin liquid phase transform under symmetry, remains to be determined. Following a Chern-Simons field theory, we show how PSG determines measurable properties of a Z2 spin liquid, such as the existence of symmetry protected gapless edge states. This fact enables us to unify two distinct types of projected wavefunctions for Z2 spin liquids: the Schwinger-boson states and the fermionic spinon states. We also provide concrete predictions for identifying the spin liquid ground state on the kagome lattice.
Introduction to Effective Field Theories - Lecture 11

Cliff Burgess McMaster University

February 14, 2014

PIRSA:14020089
How universal is the entanglement spectrum?

Anushya Chandran Perimeter Institute for Theoretical Physics

February 14, 2014

PIRSA:14020132

It is now commonly believed that the ground state entanglement spectrum (ES) exhibits universal features characteristic of a given phase. In this talk, I will present evidence to the contrary. I will show that the entanglement Hamiltonian can undergo quantum phase transitions in which its ground state and low energy spectrum exhibit singular changes, even when the physical system remains in the same phase. For broken symmetry problems, this implies that the ES and the Renyi entropies can mislead entirely, while for quantum Hall systems the ES has much less universal content than assumed to date. I will also discuss the consequences of the eigenstate thermalization hypothesis for the entanglement Hamiltonian, showing that a pure state in a sub-system can capture the properties of the reduced density matrix.
13/14 PSI - Condensed Matter Review - Lecture 14

Alioscia Hamma University of Naples Federico II

February 14, 2014

PIRSA:14020107
Challenges in Mathematical Ecology 3: Infectious diseases

Simon Levin

February 13, 2014

SAIFR:7

Physics
Introduction to Quantum Field Theory for Cosmology - Lecture 12

Achim Kempf University of Waterloo

February 13, 2014

PIRSA:14020005
Introduction to Quantum Field Theory for Cosmology - Lecture 11

Achim Kempf University of Waterloo

February 13, 2014

PIRSA:14020001
Probabilistic protocols in quantum information

Joshua Combes University of Colorado Boulder

February 13, 2014

PIRSA:14020138

Quantum Physics

Probabilistic protocols in quantum information are an attempt to improve performance by occasionally reporting a better result than could be expected from a deterministic protocol. Here we show that probabilistic protocols can never improve performance beyond the quantum limits on the corresponding deterministic protocol. To illustrate this result we examine three common probabilistic protocols: probabilistic amplification, weak value amplification, and probabilistic metrology. In each of these protocols we show explicitly that the optimal deterministic protocol is better than the corresponding probabilistic protocol when the probabilistic nature of the protocol is correctly accounted for.
Firewall evasion by quantum gravity

Ted Jacobson University of Maryland, College Park

February 13, 2014

PIRSA:14020136

General Relativity & Quantum Cosmology

It has been argued that if black hole evaporation is a unitary quantum process, then a black hole horizon must be cloaked by a "firewall", i.e. a highly excited state of local quantum fields. This reasoning is based on factorizing the Hilbert space into interior and exterior degrees of freedom. Such factorization ignores the Wheeler-deWitt constraint equation, which arises from the diffeomorphism invariance of quantum gravity. I will argue that this constraint evades the firewall.

Title	Speaker(s)	Date	Collection	Type	Info
13/14 PSI - Cosmology Review - Lecture 13		2014‑02‑14	13/14 PSI - Cosmology Review	Course	View details
Low Spin State Mott Insulators and Emergence of novel Quantum Spin Liquids		2014‑02‑14	Emergence in Complex Systems	Conference	View details
13/14 PSI - String Theory Review - Lecture 14		2014‑02‑14	13/14 PSI - String Theory Review	Course	View details
A unification of symmetric Z2 spin liquids on kagome lattice		2014‑02‑14	Emergence in Complex Systems	Conference	View details
Introduction to Effective Field Theories - Lecture 11		2014‑02‑14	Introduction to Effective Field Theories	Course	View details
How universal is the entanglement spectrum?		2014‑02‑14	Emergence in Complex Systems	Conference	View details
13/14 PSI - Condensed Matter Review - Lecture 14		2014‑02‑14	13/14 PSI - Condensed Matter Review	Course	View details
Challenges in Mathematical Ecology 3: Infectious diseases	Simon Levin	2014‑02‑13	ICTP-SAIFR Activities	Conference	View details
Introduction to Quantum Field Theory for Cosmology - Lecture 12		2014‑02‑13	Quantum Field Theory for Cosmology - 2014	Course	View details
Introduction to Quantum Field Theory for Cosmology - Lecture 11		2014‑02‑13	Quantum Field Theory for Cosmology - 2014	Course	View details
Probabilistic protocols in quantum information		2014‑02‑13	Perimeter Institute Quantum Discussions	Scientific Series	View details
Firewall evasion by quantum gravity		2014‑02‑13	Quantum Gravity	Scientific Series	View details

Supported by

Format results

13/14 PSI - Cosmology Review - Lecture 13

Low Spin State Mott Insulators and Emergence of novel Quantum Spin Liquids

13/14 PSI - String Theory Review - Lecture 14

A unification of symmetric Z2 spin liquids on kagome lattice

Introduction to Effective Field Theories - Lecture 11

How universal is the entanglement spectrum?

13/14 PSI - Condensed Matter Review - Lecture 14

Challenges in Mathematical Ecology 3: Infectious diseases

Introduction to Quantum Field Theory for Cosmology - Lecture 12

Introduction to Quantum Field Theory for Cosmology - Lecture 11

Probabilistic protocols in quantum information

Firewall evasion by quantum gravity

13/14 PSI - Cosmology Review - Lecture 13

Low Spin State Mott Insulators and Emergence of novel Quantum Spin Liquids

13/14 PSI - String Theory Review - Lecture 14

A unification of symmetric Z2 spin liquids on kagome lattice

Introduction to Effective Field Theories - Lecture 11

How universal is the entanglement spectrum?

13/14 PSI - Condensed Matter Review - Lecture 14

Challenges in Mathematical Ecology 3: Infectious diseases

Introduction to Quantum Field Theory for Cosmology - Lecture 12

Introduction to Quantum Field Theory for Cosmology - Lecture 11

Probabilistic protocols in quantum information

Firewall evasion by quantum gravity