Low Energy Challenges for High Energy Physicists

Quantum matter without quasiparticles

Subir Sachdev
Harvard University

May 29, 2014

PIRSA:14050109
Effective theories of vortex lines

Riccardo Penco
University of Pennsylvania

May 29, 2014

PIRSA:14050103
Spontaneous symmetry breaking, gravity, and spinning objects

Solomon Endlich
Stanford University

May 29, 2014

PIRSA:14050111
Lattice models for anomalous field theories

John McGreevy
University of California, San Diego

May 29, 2014

PIRSA:14050110
Relativity of non relativistic systems

Federico Piazza
Aix-Marseille University

May 30, 2014

PIRSA:14050113
Functional renormalization group and statistical mechanics of membranes

Omar Zanusso
SISSA Scuola Internazionale Superiore di Studi Avanzati

May 30, 2014

PIRSA:14050115
Dynamical trapping near a quantum critical point

Emanuel Katz
Boston College

May 30, 2014

PIRSA:14050116

Quantum matter without quasiparticles

Subir Sachdev
Harvard University

May 29, 2014

PIRSA:14050109

Modern materials abound in systems to which the quasiparticle picture does not apply, and developing their theoretical description remains an important challenge in condensed matter physics. I will describe recent progress in understanding the dynamics of two systems without quasiparticles: (i) ultracold atoms in optical lattices, and (ii) the nematic quantum critical point of metals with applications to the `strange metal’ found in the high temperature superconductors. A combination of field-theoretic, holographic, and numerical methods will be used.
Effective theories of vortex lines

Riccardo Penco
University of Pennsylvania

May 29, 2014

PIRSA:14050103

Vortex lines are a distinctive feature of superfluids and are characterized by a very peculiar dynamics. In this talk, I will first discuss the behavior of vortex lines in a non-relativistic superfluids in the incompressible limit. I will then introduce an effective theory of vortex lines coupled to sound which applies to relativistic superfluids. I will conclude by briefly discussing the similarities between the effective theory for vortex lines and non-relativistic General Relativity.
Spontaneous symmetry breaking, gravity, and spinning objects

Solomon Endlich
Stanford University

May 29, 2014

PIRSA:14050111

Space-time symmetries are a crucial ingredient of any theoretical model in physics. Unlike internal symmetries, which may or may not be gauged and/or spontaneously broken, space-time symmetries do not admit any ambiguity: they are gauged by gravity, and any conceivable physical system (other than the vacuum) is bound to break at least some of them. Motivated by this observation, I will sketch how to couple gravity with the Goldstone fields that non-linearly realize spontaneously broken space-time symmetries by weakly gauging the Poincare symmetry group in the context of the coset construction. To illustrate the power of this perspective I will build a low energy effective action that describes spinning objects coupled to gravity and describe its interpretation.
Lattice models for anomalous field theories

John McGreevy
University of California, San Diego

May 29, 2014

PIRSA:14050110
Relativity of non relativistic systems

Federico Piazza
Aix-Marseille University

May 30, 2014

PIRSA:14050113

To the best of our knowledge, the fundamental laws of physics are Lorentz invariant. This means that condensed matter systems at finite density still display full Lorentz symmetry: it is just spontaneously broken (i.e. by state considered) and thus non-linearly realized. This simple observation allows to derive exact results about the spectrum of theories at finite charge density and suggests to classify condensed matter systems according to all the inequivalent ways in which boosts can be spontaneously broken.
Functional renormalization group and statistical mechanics of membranes

Omar Zanusso
SISSA Scuola Internazionale Superiore di Studi Avanzati

May 30, 2014

PIRSA:14050115

We will first review the rich variety of universality classes of membranes and the various models developed to describe their mechanical properties. We will then discuss the recent applications of the non-perturbative renormalization group to these models aimed at improving the understanding of the membranes' phase-space beyond the epsilon-expansion. Finally, we will comment on the implications of these results on various physical systems.
Dynamical trapping near a quantum critical point

Emanuel Katz
Boston College

May 30, 2014

PIRSA:14050116

We consider a closed system where the parameter controlling a quantum phase transition is promoted to a dynamical field interacting with the quantum critical theory. In the case that the field has an energy extensive in the volume we can treat its evolution classically. We find that the field can become trapped near the phase transition point due to its interactions with the degrees of freedom of the quantum critical theory. The trapping/untrapping transition can be understood using Kibble-Zurek scaling arguments. We check the general framework numerically in the particular case of the 1D transverse field Ising chain, where the transverse magnetic field is dynamical. This constitutes a dynamical mechanism for tuning a relevant parameter to zero through a non-equilibrium process.

Title	Speaker(s)	Date	Talk Type	Info
Quantum matter without quasiparticles	Subir Sachdev	2014-05-29	Conference	View details
Effective theories of vortex lines	Riccardo Penco	2014-05-29	Conference	View details
Spontaneous symmetry breaking, gravity, and spinning objects	Solomon Endlich	2014-05-29	Conference	View details
Lattice models for anomalous field theories	John McGreevy	2014-05-29	Conference	View details
Relativity of non relativistic systems	Federico Piazza	2014-05-30	Conference	View details
Functional renormalization group and statistical mechanics of membranes	Omar Zanusso	2014-05-30	Conference	View details
Dynamical trapping near a quantum critical point	Emanuel Katz	2014-05-30	Conference	View details

Low Energy Challenges for High Energy Physicists

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