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Universal problems

David Mattingly University of New Hampshire
April 17, 2014

PIRSA:14040074
General Relativity & Quantum Cosmology
13/14 PSI - Explorations in Cosmology - Lecture 9

Matthew Johnson York University

April 17, 2014

PIRSA:14040051
13/14 PSI - Explorations in Particle Theory - Lecture 9

Brian Shuve Harvey Mudd College

April 17, 2014

PIRSA:14030058
Exact Classical Simulation of the Quantum-Mechanical GHZ Distribution

Gilles Brassard Université de Montréal
April 16, 2014

PIRSA:14040060
Quantum Physics
13/14 PSI - Explorations in Cosmology - Lecture 8

Matthew Johnson York University

April 16, 2014

PIRSA:14040050
13/14 PSI - Explorations in Particle Theory - Lecture 8

Brian Shuve Harvey Mudd College

April 16, 2014

PIRSA:14030055
Categories of Convex Sets and C*-Algebras

Robert Furber Radboud Universiteit Nijmegen
April 15, 2014

PIRSA:14040140
Quantum Physics
Boson Tagging with Wavelets

William Shepherd University of California System
April 15, 2014

PIRSA:14040063
High Energy Physics
Groups and Clusters of Galaxies: Where Cosmology and Astrophysics Collide

Arif Babul University of Victoria
April 15, 2014

PIRSA:14040133
Astrophysics
13/14 PSI - Explorations in Cosmology - Lecture 7

Matthew Johnson York University

April 15, 2014

PIRSA:14040049
New Exact Results in Calabi-Yau, D-branes, and Orientifolds

Sungjay Lee University of Cambridge
April 15, 2014

PIRSA:14040081
High Energy Physics
13/14 PSI - Explorations in Particle Theory - Lecture 7

Brian Shuve Harvey Mudd College

April 15, 2014

PIRSA:14030054

Universal problems

David Mattingly University of New Hampshire
April 17, 2014

PIRSA:14040074
General Relativity & Quantum Cosmology
Arguments that gravity cannot be a local renormalizable quantum field theory come from both field theory lore and black hole physics. Two current approaches to quantum gravity, asymptotic safety and Horava-Lifshitz gravity, both of which treat quantum gravity as a local renormalizable QFT, are explicitly constructed to counter field theory arguments about the non-renormalizability of gravity. However, any proposed renormalizable theory of quantum gravity must also answer black hole physics based counter-arguments. Formulating these arguments concretely requires understanding black hole solutions and thermodynamics in these theories. For Horava-Lifshitz gravity this entails understanding the thermodynamics of universal horizons. I describe the current status of universal horizon physics and which aspects are/are not still in tension with the fundamental premise of renormalizability.
13/14 PSI - Explorations in Cosmology - Lecture 9

Matthew Johnson York University

April 17, 2014

PIRSA:14040051
13/14 PSI - Explorations in Particle Theory - Lecture 9

Brian Shuve Harvey Mudd College

April 17, 2014

PIRSA:14030058
Exact Classical Simulation of the Quantum-Mechanical GHZ Distribution

Gilles Brassard Université de Montréal
April 16, 2014

PIRSA:14040060
Quantum Physics
John Bell has shown that the correlations entailed by quantum mechanics cannot be reproduced by a classical process involving non-communicating parties. But can they be simulated with the help of bounded communication? This problem has been studied for more than twenty years and it is now well understood in the case of bipartite entanglement. However, the issue was still widely open for multipartite entanglement, even for the simplest case, which is the tripartite Greenberger-Horne-Zeilinger (GHZ) state. We give an exact simulation of arbitrary independent von Neumann measurements on general n-partite GHZ states. Our protocol requires O(n^2) bits of expected communication between the parties, and O(n log n) expected time is sufficient to carry it out in parallel. Furthermore, we need only an expectation of O(n) independent unbiased random bits, with no need for the generation of continuous real random variables nor prior shared random variables. In the case of equatorial measurements, we improve earlier results with a protocol that needs only O(n log n) bits of communication and O(log^2 n) parallel time. At the cost of a slight increase in the number of bits communicated, these tasks can be accomplished with a constant expected number of rounds.
13/14 PSI - Explorations in Cosmology - Lecture 8

Matthew Johnson York University

April 16, 2014

PIRSA:14040050
13/14 PSI - Explorations in Particle Theory - Lecture 8

Brian Shuve Harvey Mudd College

April 16, 2014

PIRSA:14030055
Categories of Convex Sets and C*-Algebras

Robert Furber Radboud Universiteit Nijmegen
April 15, 2014

PIRSA:14040140
Quantum Physics
The start of the talk will be an outline how the ordinary notions of quantum theory translate into the category of C*-algebras, where there are several possible choices of morphisms. The second half will relate this to a category of convex sets used as state spaces. Alfsen and Shultz have characterized the convex sets arising from state spaces C*-algebras and this result can be applied to get a categorical equivalence between C*-algebras and state spaces of C*-algebras which is a generalization of the equivalence between the Schroedinger and Heisenberg pictures.
Boson Tagging with Wavelets

William Shepherd University of California System
April 15, 2014

PIRSA:14040063
High Energy Physics
I'll present a proof-of-concept new technique for tagging boosted objects which decay into two colored particles based on the wavelet transform. It is able to moderately improve the sensitivity of searches for such particles by 6-7%. I will also discuss future directions of applicability.
Groups and Clusters of Galaxies: Where Cosmology and Astrophysics Collide

Arif Babul University of Victoria
April 15, 2014

PIRSA:14040133
Astrophysics
Groups and clusters of galaxies are the most massive gravitationally bound objects in the Universe. They are also the most recent cosmic objects to form. In the currently accepted models of cosmic structure formation, the number density distribution of the most massive of these systems, and how this has been changing with time, depend sensitively to the parameters describing the large-scale geometry and the expansion history of the universe. However, to exploit galaxy clusters as cosmological probes, we must be able to relate their observable properties to their total mass. I will discuss our ongoing effort to calibrate the X-ray/SZ observations to the total mass for the 50 clusters comprising the Canadian Cluster Comparison Project (CCCP) sample. Resulting scaling relations, the associated scatter, and even how these change with time, invariably depend on "astrophysics" unfolding in these systems. The precision with which the cosmological parameters can be determined depends critically on how well we understand why groups and clusters manifest the observed properties that they do. This, however, has proven challenging. I will provide an update of the current state of affairs and highlight some of the key gaps in our understanding of the underlying physics.
13/14 PSI - Explorations in Cosmology - Lecture 7

Matthew Johnson York University

April 15, 2014

PIRSA:14040049
New Exact Results in Calabi-Yau, D-branes, and Orientifolds

Sungjay Lee University of Cambridge
April 15, 2014

PIRSA:14040081
High Energy Physics
We compute the exact two-sphere, disk and real projective plane partition functions of two-dimensional supersymmetric theories using the localization technique. From these new results, we will attack old and new important problems in the string theory on Calabi-Yau spaces, and D-branes and Orientifold planes therein.
13/14 PSI - Explorations in Particle Theory - Lecture 7

Brian Shuve Harvey Mudd College

April 15, 2014

PIRSA:14030054

Title	Date	Collection	Type	Info
Universal problems	2014‑04‑17	Quantum Gravity	Scientific Series	View details
13/14 PSI - Explorations in Cosmology - Lecture 9	2014‑04‑17	13/14 PSI - Explorations in Cosmology	Course	View details
13/14 PSI - Explorations in Particle Theory - Lecture 9	2014‑04‑17	13/14 PSI - Explorations in Particle Theory	Course	View details
Exact Classical Simulation of the Quantum-Mechanical GHZ Distribution	2014‑04‑16	Colloquium	Scientific Series	View details
13/14 PSI - Explorations in Cosmology - Lecture 8	2014‑04‑16	13/14 PSI - Explorations in Cosmology	Course	View details
13/14 PSI - Explorations in Particle Theory - Lecture 8	2014‑04‑16	13/14 PSI - Explorations in Particle Theory	Course	View details
Categories of Convex Sets and C*-Algebras	2014‑04‑15	Quantum Foundations	Scientific Series	View details
Boson Tagging with Wavelets	2014‑04‑15	Particle Physics	Scientific Series	View details
Groups and Clusters of Galaxies: Where Cosmology and Astrophysics Collide	2014‑04‑15	Cosmology and Gravitation	Scientific Series	View details
13/14 PSI - Explorations in Cosmology - Lecture 7	2014‑04‑15	13/14 PSI - Explorations in Cosmology	Course	View details
New Exact Results in Calabi-Yau, D-branes, and Orientifolds	2014‑04‑15	Quantum Fields and Strings	Scientific Series	View details
13/14 PSI - Explorations in Particle Theory - Lecture 7	2014‑04‑15	13/14 PSI - Explorations in Particle Theory	Course	View details

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Format results

Universal problems

13/14 PSI - Explorations in Cosmology - Lecture 9

13/14 PSI - Explorations in Particle Theory - Lecture 9

Exact Classical Simulation of the Quantum-Mechanical GHZ Distribution

13/14 PSI - Explorations in Cosmology - Lecture 8

13/14 PSI - Explorations in Particle Theory - Lecture 8

Categories of Convex Sets and C*-Algebras

Boson Tagging with Wavelets

Groups and Clusters of Galaxies: Where Cosmology and Astrophysics Collide

13/14 PSI - Explorations in Cosmology - Lecture 7

New Exact Results in Calabi-Yau, D-branes, and Orientifolds

13/14 PSI - Explorations in Particle Theory - Lecture 7

Universal problems

13/14 PSI - Explorations in Cosmology - Lecture 9

13/14 PSI - Explorations in Particle Theory - Lecture 9

Exact Classical Simulation of the Quantum-Mechanical GHZ Distribution

13/14 PSI - Explorations in Cosmology - Lecture 8

13/14 PSI - Explorations in Particle Theory - Lecture 8

Categories of Convex Sets and C*-Algebras

Boson Tagging with Wavelets

Groups and Clusters of Galaxies: Where Cosmology and Astrophysics Collide

13/14 PSI - Explorations in Cosmology - Lecture 7

New Exact Results in Calabi-Yau, D-branes, and Orientifolds

13/14 PSI - Explorations in Particle Theory - Lecture 7