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Inflation, Variable Speed of Light and BICEP2

John Moffat Perimeter Institute for Theoretical Physics
June 12, 2014

PIRSA:14060044
Cosmology
Sequential growth dynamics and quantum random walks

David Meyer University of California, San Diego
June 11, 2014

PIRSA:14060042
Mathematical physics
Wild and tame scalar-tensor black holes

Valerio Faraoni Bishop's University
June 10, 2014

PIRSA:14060043
Cosmology
Neutrino Wakes

Ue-Li Pen Canadian Institute for Theoretical Astrophysics (CITA)
June 06, 2014

PIRSA:14060041
Cosmology
Quantum technologies as tools to deepen our understanding of quantum theory and relativity

Ivette Fuentes University of Southampton
June 05, 2014

PIRSA:14060006
Quantum Information
From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg

S. James Gates Jr. University of Maryland, College Park

June 04, 2014

PIRSA:14060048
How Much Information Can SUSY QM Conserve About SUSY QFT (Part-2)?

S. James Gates Jr. University of Maryland, College Park

June 04, 2014

PIRSA:14060005
Gauge fields in de Sitter space: antipodal symmetry and holography

Yasha Neiman Okinawa Institute of Science and Technology Graduate University
June 03, 2014

PIRSA:14060039
Quantum Fields and Strings
Some Conceptual Problems in General Relativity and Cosmology

Jayant Narlikar IUCAA - The Inter-University Centre for Astronomy and Astrophysics
June 03, 2014

PIRSA:14060004
Cosmology
Dynamical trapping near a quantum critical point

Emanuel Katz Boston University

May 30, 2014

PIRSA:14050116
Functional renormalization group and statistical mechanics of membranes

Omar Zanusso SISSA Scuola Internazionale Superiore di Studi Avanzati

May 30, 2014

PIRSA:14050115
Relativity of non relativistic systems

Federico Piazza Aix-Marseille University

May 30, 2014

PIRSA:14050113

Inflation, Variable Speed of Light and BICEP2

John Moffat Perimeter Institute for Theoretical Physics
June 12, 2014

PIRSA:14060044
Cosmology
A variable speed of light (VSL) cosmology is developed with a spontaneous breaking of Lorentz invariance in the early universe. A non-minimal electromagnetic coupling to curvature and the resulting quantum electrodynamic vacuum polarization dispersive medium can produce c >> c0 in the early universe, where c0 is the measured speed of light today. Higher derivative curvature contributions to the effective gravitational action and quantum gravity vacuum polarization can produce a dispersive medium and a large increase in the speed of gravitational waves cg >> cg0 in the early universe, where cg0 is the speed of gravitational waves today. The initial value problems of cosmology are solved: the horizon and flatness problems. The model predicts primordial scalar and tensor fluctuation spectral indices ns=0.96 and nt=- 0.04, respectively. The BICEP2 observation of r=0.2 yields r/nt=-5 which is close to the single-field inflationary consistency condition r/nt=-8.
Sequential growth dynamics and quantum random walks

David Meyer University of California, San Diego
June 11, 2014

PIRSA:14060042
Mathematical physics
Rideout and Sorkin proposed a classical dynamics for causal sets based upon a sequential growth model. Comparing it with models for sequential growth in other systems, and with the dual goals of generating manifold-like causal sets and finding a quantum dynamics for them, we propose some modifications to their model. The resulting, admittedly speculative, proposal is a type of quantum random walk. We explore its properties in some simple cases.
Wild and tame scalar-tensor black holes

Valerio Faraoni Bishop's University
June 10, 2014

PIRSA:14060043
Cosmology
In scalar-tensor gravity, black holes do not obey the Jebsen-Birkhoff theorem. Non-isolated black holes can be highly dynamical and the teleological concept of event horizon is replaced by the apparent or trapping horizon. Dynamical solutions describing inhomogeneities embedded in cosmological "backgrounds" and the phenomenology of their apparent horizons, which often appear/vanish in pairs, will be described. Isolated black holes, in contrast, have no hair and are the same as in general relativity.
Neutrino Wakes

Ue-Li Pen Canadian Institute for Theoretical Astrophysics (CITA)
June 06, 2014

PIRSA:14060041
Cosmology
We identify a new non-linear neutrino wake effect, due to the streaming motions of neutrinos relative to dark matter, analogous to the Tseliakhovich-Hirata effect. We compute the effect in moving background perturbation theory, compare to direct n-body simulations, and forecast its observability in current and future surveys. Depending on neutrino mass, this effect could be observable in upcoming surveys through a cross correlation dipole in lensing and galaxies. Unlike previous cosmological neutrino effects, this depends primarily on neutrino mass, making it complementary to measurements that depend on neutrino density.
Quantum technologies as tools to deepen our understanding of quantum theory and relativity

Ivette Fuentes University of Southampton
June 05, 2014

PIRSA:14060006
Quantum Information
Quantum information and quantum metrology can be used to study gravitational effects such as gravitational waves and the universality of the equivalence principle. On one hand, the possibility of carrying out experiments to probe gravity using quantum systems opens an avenue to deepen our understanding of the overlap of these theories. On the other hand, incorporating relativity in quantum technologies promises the development of a new generation of relativistic quantum applications of relevance in Earth-based and space-based setups. In this talk, I will introduce a framework for the application of quantum information and quantum metrology techniques to relativistic quantum fields. I will show how, using this framework, we have been able to develop an accelerometer and a gravitational wave detector which exploit both quantum and relativistic effects. Moreover, our framework can be used to estimate with high precision spacetime parameters such as the Earth's Schwarzchild radius and the gravitational constant.
From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg

S. James Gates Jr. University of Maryland, College Park

June 04, 2014

PIRSA:14060048

The concept of supersymmetry, though never observed in nature, has driven a great deal of research in theoretical physics over the past several decades. Much has been learned through this research, but many unresolved questions remain. This presentation will describe how these questions can lead one down a surprising path: toward the dodecaphony of Austrian composer Arnold Schoenberg.
How Much Information Can SUSY QM Conserve About SUSY QFT (Part-2)?

S. James Gates Jr. University of Maryland, College Park

June 04, 2014

PIRSA:14060005

We provide additional evidence that supersymmetrical quantum mechanical systems can contain a remarkable amount of information about supersymmetrical field
theories in greater than one dimension.
Gauge fields in de Sitter space: antipodal symmetry and holography

Yasha Neiman Okinawa Institute of Science and Technology Graduate University
June 03, 2014

PIRSA:14060039
Quantum Fields and Strings
There is a proposed dS/CFT duality in 3+1 dimensions, with higher-spin gravity in the bulk subject to Bunch-Davies boundary conditions. I consider replacing these with antipodally symmetric conditions, which allow for real values of the bulk fields. I present spanning sets of solutions in global dS_4 for free gauge fields of all spins (including photons and gravitons), and use them to establish relations between antipodal symmetry and asymptotic behavior. Some of these relations can be extended to interacting theories, including ordinary and higher-spin gravity. I discuss the implications for antipodally symmetric dS/CFT.
Some Conceptual Problems in General Relativity and Cosmology

Jayant Narlikar IUCAA - The Inter-University Centre for Astronomy and Astrophysics
June 03, 2014

PIRSA:14060004
Cosmology
This talk will try to highlight some basic problems connected with conclusions uncritically drawn from well known works. These include: 1. The Schwarzschild solution 2. The formation of black holes by gravitational collapse 3. The no hair theorem 4. The principle of equivalence in the very early universe.
Dynamical trapping near a quantum critical point

Emanuel Katz Boston University

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.
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.
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.

Title	Date	Collection	Type	Info
Inflation, Variable Speed of Light and BICEP2	2014‑06‑12	Cosmology and Gravitation	Scientific Series	View details
Sequential growth dynamics and quantum random walks	2014‑06‑11	Colloquium	Scientific Series	View details
Wild and tame scalar-tensor black holes	2014‑06‑10	Cosmology and Gravitation	Scientific Series	View details
Neutrino Wakes	2014‑06‑06	Colloquium	Scientific Series	View details
Quantum technologies as tools to deepen our understanding of quantum theory and relativity	2014‑06‑05	Perimeter Institute Quantum Discussions	Scientific Series	View details
From the Mathematics of Supersymmetry to the Music of Arnold Schoenberg	2014‑06‑04	Public Lecture Series	Public Lectures	View details
How Much Information Can SUSY QM Conserve About SUSY QFT (Part-2)?	2014‑06‑04	Colloquium	Scientific Series	View details
Gauge fields in de Sitter space: antipodal symmetry and holography	2014‑06‑03	Quantum Fields and Strings	Scientific Series	View details
Some Conceptual Problems in General Relativity and Cosmology	2014‑06‑03	Cosmology and Gravitation	Scientific Series	View details
Dynamical trapping near a quantum critical point	2014‑05‑30	Low Energy Challenges for High Energy Physicists	Conference	View details
Functional renormalization group and statistical mechanics of membranes	2014‑05‑30	Low Energy Challenges for High Energy Physicists	Conference	View details
Relativity of non relativistic systems	2014‑05‑30	Low Energy Challenges for High Energy Physicists	Conference	View details

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