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Neutron Stars and the Dense Matter Equation of State

Madappa Prakash Ohio University
August 08, 2013

PIRSA:13080000
General Relativity & Quantum Cosmology
Effective Field Theory of Multi-Field Inflation a la Weinberg

Nima Khosravi Shahid Beheshti University
July 30, 2013

PIRSA:13070091
Astrophysics
Quantum Cosmology - 5
- Hector Hernandez Universidad Autonoma de Chihuahua
- Edison Montoya Universidad de Antioquia
- Matthew Hogan
- Francesca Vidotto Western University
July 26, 2013

PIRSA:13070087
Quantum Foundations - 2
- David Schroeren University of Oxford
- Paolo Bertozzini Thammasat University
- Bruno Hartmann
July 26, 2013

PIRSA:13070088
Mixed Session
- Valerio Astuti
- Seth Major Hamilton College
- Michael Reisenberger Universidad de la Republica Uruguay
- Jacobo Diaz-Polo
July 26, 2013

PIRSA:13070090
Renormalization - 3
- Tobias Henz Universität Heidelberg - Institut für Theoretische Physik
- Kevin Falls University of Sussex
- Mohamed Anber Canadian Institute for Theoretical Astrophysics (CITA)
July 26, 2013

PIRSA:13070089
Discrete Approaches and Mixed Session
- Goffredo Chirco Max Planck Institute for Gravitational Physics - Albert Einstein Institute (AEI)
- Eugene Kur University of California, Berkeley
- Christopher Duston Florida State University
- Johannes Thuerigen University of Münster
- Bianca Dittrich Perimeter Institute for Theoretical Physics
July 26, 2013

PIRSA:13070085
Quantum Cosmology - 4
- Daniel Martin de Blas Universidade Federal do Espírito Santo
- Adriano Contillo Radboud Universiteit Nijmegen
- Marcin Kisielowski University of Warsaw
- Eduardo Martin-Martinez University of Waterloo
July 26, 2013

PIRSA:13060026
Quantum Foundations - 1
- Lee Smolin Perimeter Institute for Theoretical Physics
- Robert Spekkens Perimeter Institute for Theoretical Physics
- Robert Oeckl Universidad Nacional Autónoma De Mexico (UNAM)
- Jonathan Oppenheim University College London
- Markus Müller Institute for Quantum Optics and Quantum Information (IQOQI) - Vienna
July 26, 2013

PIRSA:13070084
Canonical Quantum Gravity and Spin Foams
- Antonia Zipfel
- Mingyi Zhang Aix-Marseille University
- Atousa Chaharsough Shirazi
- Fabio Anza Università di Pisa
- Aristide Baratin SAIT AI Lab Montreal
July 26, 2013

PIRSA:13070086
Promising Paths: What Have We Learned So Far About Quantum Gravity?
- Abhay Ashtekar Pennsylvania State University
- Carlo Rovelli Aix-Marseille University
July 26, 2013

PIRSA:13070083
Scenes From Polymer Quantization

Viqar Husain University of New Brunswick

July 26, 2013

PIRSA:13070082

Neutron Stars and the Dense Matter Equation of State

Madappa Prakash Ohio University
August 08, 2013

PIRSA:13080000
General Relativity & Quantum Cosmology
Implications of recently well-measured neutron star masses, particularly near and above 2 solar masses, for the equation of state (EOS) of neutron star matter will be highlighted. Model independent upper limits to thermodynamic properties in neutron stars, which only depend on the neutron star maximum mass, established from causality considerations will be presented. The need for non-perturbative treatments of quark matter in neutron stars is revealed through studies of self-bound quark matter stars, and of nucleon-quark hybrid stars. The extent to which several well-measured masses and radii of individual neutron stars can establish a model-independent EOS through an inversion of the stellar structure equations will be briefly discussed.
Effective Field Theory of Multi-Field Inflation a la Weinberg

Nima Khosravi Shahid Beheshti University
July 30, 2013

PIRSA:13070091
Astrophysics
We
employ the effective field theory approach for multi-field inflation which is a
generalization of Weinberg's work. In this method the first correction terms in
addition to standard terms in the Lagrangian have been considered. These terms
contain up to the fourth derivative of the fields including the scalar field
and the metric. The results show the possible shapes of the interaction terms
resulting eventually in non-Gaussianity in a general formalism. In addition
generally the speed of sound is different but almost unity. Since in this
method the adiabatic mode is not discriminated initially so we define the
adiabatic as well as entropy modes for a specific two-field model. It has been
shown that the non-Gaussianity of the adiabatic mode and the entropy mode are
correlated in shape and amplitude. It is shown that even for speed close to
unity large non-Gaussianities are possible in multi-field case. The amount of
the non-Gaussianity depends on the curvature of the classical path in the
phase-space in the Hubble unit such that it is large for the large curvature.
In addition it is emphasized that the time derivative of adiabatic and entropy
perturbations do not transform due to the shift symmetry as well as the
original perturbations. Though two specific combinations of them are invariant
under such a symmetry and these combinations should be employed to construct an
effective field theory of multi-field inflation.
Quantum Cosmology - 5
- Hector Hernandez Universidad Autonoma de Chihuahua
- Edison Montoya Universidad de Antioquia
- Matthew Hogan
- Francesca Vidotto Western University
July 26, 2013

PIRSA:13070087
Quantum Foundations - 2
- David Schroeren University of Oxford
- Paolo Bertozzini Thammasat University
- Bruno Hartmann
July 26, 2013

PIRSA:13070088
Mixed Session
- Valerio Astuti
- Seth Major Hamilton College
- Michael Reisenberger Universidad de la Republica Uruguay
- Jacobo Diaz-Polo
July 26, 2013

PIRSA:13070090
Renormalization - 3
- Tobias Henz Universität Heidelberg - Institut für Theoretische Physik
- Kevin Falls University of Sussex
- Mohamed Anber Canadian Institute for Theoretical Astrophysics (CITA)
July 26, 2013

PIRSA:13070089
Discrete Approaches and Mixed Session
- Goffredo Chirco Max Planck Institute for Gravitational Physics - Albert Einstein Institute (AEI)
- Eugene Kur University of California, Berkeley
- Christopher Duston Florida State University
- Johannes Thuerigen University of Münster
- Bianca Dittrich Perimeter Institute for Theoretical Physics
July 26, 2013

PIRSA:13070085
Quantum Cosmology - 4
- Daniel Martin de Blas Universidade Federal do Espírito Santo
- Adriano Contillo Radboud Universiteit Nijmegen
- Marcin Kisielowski University of Warsaw
- Eduardo Martin-Martinez University of Waterloo
July 26, 2013

PIRSA:13060026
Quantum Foundations - 1
- Lee Smolin Perimeter Institute for Theoretical Physics
- Robert Spekkens Perimeter Institute for Theoretical Physics
- Robert Oeckl Universidad Nacional Autónoma De Mexico (UNAM)
- Jonathan Oppenheim University College London
- Markus Müller Institute for Quantum Optics and Quantum Information (IQOQI) - Vienna
July 26, 2013

PIRSA:13070084
Canonical Quantum Gravity and Spin Foams
- Antonia Zipfel
- Mingyi Zhang Aix-Marseille University
- Atousa Chaharsough Shirazi
- Fabio Anza Università di Pisa
- Aristide Baratin SAIT AI Lab Montreal
July 26, 2013

PIRSA:13070086
Promising Paths: What Have We Learned So Far About Quantum Gravity?
- Abhay Ashtekar Pennsylvania State University
- Carlo Rovelli Aix-Marseille University
July 26, 2013

PIRSA:13070083

In LQG we work in the spirit of Antonio Machado: "Traveler, there is no path; Paths are made by walking." I will present a bird's eye view of some of the paths that have emerged since Loops 11 and offer a few suggestions.

I try to make the point about what we know and what we do not yet know about the possibility of writing a quantum theory of gravity.
Scenes From Polymer Quantization

Viqar Husain University of New Brunswick

July 26, 2013

PIRSA:13070082

A regime of "polymer quantum field theory on curved spacetime" should emerge in a low energy approximation of quantum gravity based on LQG ideas. This era should be characterized by a polymer scale, and give modifications to the usual semiclassical approximation. I will describe work on gravitational collapse, cosmology, and statistical mechanics in this setting. Results include models of horizon evaporation, inflation and graceful exit without an inflaton potential, and an indication of dimensional reduction from 4 to 2.5 dimensions.

Title	Date	Collection	Type	Info
Neutron Stars and the Dense Matter Equation of State	2013‑08‑08	Strong Gravity	Scientific Series	View details
Effective Field Theory of Multi-Field Inflation a la Weinberg	2013‑07‑30	Cosmology and Gravitation	Scientific Series	View details
Quantum Cosmology - 5	2013‑07‑26	Loops 13	Conference	View details
Quantum Foundations - 2	2013‑07‑26	Loops 13	Conference	View details
Mixed Session	2013‑07‑26	Loops 13	Conference	View details
Renormalization - 3	2013‑07‑26	Loops 13	Conference	View details
Discrete Approaches and Mixed Session	2013‑07‑26	Loops 13	Conference	View details
Quantum Cosmology - 4	2013‑07‑26	Loops 13	Conference	View details
Quantum Foundations - 1	2013‑07‑26	Loops 13	Conference	View details
Canonical Quantum Gravity and Spin Foams	2013‑07‑26	Loops 13	Conference	View details
Promising Paths: What Have We Learned So Far About Quantum Gravity?	2013‑07‑26	Loops 13	Conference	View details
Scenes From Polymer Quantization	2013‑07‑26	Loops 13	Conference	View details

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Format results

Neutron Stars and the Dense Matter Equation of State

Effective Field Theory of Multi-Field Inflation a la Weinberg

Quantum Cosmology - 5

Quantum Foundations - 2

Mixed Session

Renormalization - 3

Discrete Approaches and Mixed Session

Quantum Cosmology - 4

Quantum Foundations - 1

Canonical Quantum Gravity and Spin Foams

Promising Paths: What Have We Learned So Far About Quantum Gravity?

Scenes From Polymer Quantization

Neutron Stars and the Dense Matter Equation of State

Effective Field Theory of Multi-Field Inflation a la Weinberg

Quantum Cosmology - 5

Quantum Foundations - 2

Mixed Session

Renormalization - 3

Discrete Approaches and Mixed Session

Quantum Cosmology - 4

Quantum Foundations - 1

Canonical Quantum Gravity and Spin Foams

Promising Paths: What Have We Learned So Far About Quantum Gravity?

Scenes From Polymer Quantization