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Bounding the Elliptope of Quantum Correlations & Proving Separability in Mixed States

Elie Wolfe Perimeter Institute for Theoretical Physics
November 26, 2013

PIRSA:13110092
Quantum Physics
Classical Space Times from S Matrices

Ira Rothstein Carnegie Mellon University
November 26, 2013

PIRSA:13110053
High Energy Physics
BiGravity: from Cosmological Solutions to Dual Galileons

Matteo Fasiello University of Portsmouth
November 26, 2013

PIRSA:13110093
Astrophysics
13/14 PSI - Condensed Matter - Lecture 12
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 26, 2013

PIRSA:13110042
13/14 PSI - Quantum Field Theory II - Lecture 12

Francois David CEA Saclay

November 26, 2013

PIRSA:13110023
13/14 PSI - Condensed Matter - Lecture 11
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 25, 2013

PIRSA:13110041
13/14 PSI - Quantum Field Theory II - Lecture 11

Francois David CEA Saclay

November 25, 2013

PIRSA:13110022
13/14 PSI - Condensed Matter - Lecture 10
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 22, 2013

PIRSA:13110038
13/14 PSI - Quantum Field Theory II - Lecture 10

Francois David CEA Saclay

November 22, 2013

PIRSA:13110019
General Relativity for Cosmology - Lecture 20

Achim Kempf University of Waterloo

November 21, 2013

PIRSA:13110006
General Relativity for Cosmology - Lecture 19

Achim Kempf University of Waterloo

November 21, 2013

PIRSA:13110002
Dimensional reduction in the sky
November 21, 2013

PIRSA:13110059
General Relativity & Quantum Cosmology

Bounding the Elliptope of Quantum Correlations & Proving Separability in Mixed States

Elie Wolfe Perimeter Institute for Theoretical Physics
November 26, 2013

PIRSA:13110092
Quantum Physics
We present a method for determining the maximum possible violation of any linear Bell inequality per quantum mechanics. Essentially this amounts to a constrained optimization problem for an observable’s eigenvalues, but the problem can be reformulated so as to be analytically tractable. This opens the door for an arbitrarily precise characterization of quantum correlations, including allowing for non-random marginal expectation values. Such a characterization is critical when contrasting QM to superficially similar general probabilistic theories. We use such marginal-involving quantum bounds to estimate the volume of all possible quantum statistics in the complete 8-dimensional probability space of the Bell-CHSH scenario, measured relative to both local hidden variable models as well as general no-signaling theories. See arXiv:1106.2169. Time permitting, we’ll also discuss how one might go about trying to prove that a given mixed state is, in fact, not entangled. (The converse problem of certifying non-zero entanglement has received extensive treatment already.) Instead of directly asking if any separable representation exists for the state, we suggest simply checking to see if it “fits” some particular known-separable form. We demonstrate how a surprisingly valuable sufficient separability criterion follows merely from considering a highly-generic separable form. The criterion we generate for diagonally-symmetric mixed states is apparently completely tight, necessary and sufficient. We use integration to quantify the “volume” of states captured by our criterion, and show that it is as large as the volume of states associated with the PPT criterion; this simultaneously proves our criterion to be necessary as well as the PPT criterion to be sufficient, on this family of states. The utility of a sufficient separability criterion is evidenced by categorically rejecting Dicke-model superradiance for entanglement generation schema. See arXiv:1307.5779.
Classical Space Times from S Matrices

Ira Rothstein Carnegie Mellon University
November 26, 2013

PIRSA:13110053
High Energy Physics
Progress in calculating S matrix elements have shown that the malicious redundancies in non-linear gauge theories can be circumvented by utilizing unitarity methods in conjunction with BCFW recursion relations. When calculating in this fashion all of the interaction vertices beyond the three point function can be ignored. This simplification is especially useful in gravity which contains an infinite number of such non-linear interactions. It is natural to ask whether off-shell quantities, such as classical solutions, can also be generated using only the three point vertex. In this talk I will show that this is indeed the case by extracting classical solutions to GR from on-hell two to two scattering S-matrix elements. In so doing we will completely circumvent the action as well as the equations of motion. The only inputs will be Lorentz invariance, the existence of a massless spin-two particle and locality. Because of the double copy relation this implies there exists, a yet to be understood, connection between solutions to Yang-Mills theory and Gravity. I will also discuss how this technique can be used to simplify calculations of higher order post-Newtonian corrections to gravitational potentials relevant to the problem of binary inspirals.
BiGravity: from Cosmological Solutions to Dual Galileons

Matteo Fasiello University of Portsmouth
November 26, 2013

PIRSA:13110093
Astrophysics
I will present Cosmological FRW Solutions in BiGravity Theories and discuss their stability. After deriving the stability bound, one realizes that in Bigravity (in contradistinction to the FRW massive gravity case) the tension between requirements stemming from stability and those set by observations is resolved. The stability bound can also be derived in the decoupling limit of Bigravity. In this context an intriguing duality between Galilean interactions has emerged.
13/14 PSI - Condensed Matter - Lecture 12
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 26, 2013

PIRSA:13110042
13/14 PSI - Quantum Field Theory II - Lecture 12

Francois David CEA Saclay

November 26, 2013

PIRSA:13110023
13/14 PSI - Condensed Matter - Lecture 11
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 25, 2013

PIRSA:13110041
13/14 PSI - Quantum Field Theory II - Lecture 11

Francois David CEA Saclay

November 25, 2013

PIRSA:13110022
13/14 PSI - Condensed Matter - Lecture 10
- Anushya Chandran Perimeter Institute for Theoretical Physics
- Roger Melko University of Waterloo
- Xiao-Gang Wen Massachusetts Institute of Technology (MIT) - Department of Physics
November 22, 2013

PIRSA:13110038
13/14 PSI - Quantum Field Theory II - Lecture 10

Francois David CEA Saclay

November 22, 2013

PIRSA:13110019
General Relativity for Cosmology - Lecture 20

Achim Kempf University of Waterloo

November 21, 2013

PIRSA:13110006
General Relativity for Cosmology - Lecture 19

Achim Kempf University of Waterloo

November 21, 2013

PIRSA:13110002
Dimensional reduction in the sky
November 21, 2013

PIRSA:13110059
General Relativity & Quantum Cosmology
In several approaches to quantum-gravity, the spectral dimension of spacetime runs from the standard value of 4 in the infrared (IR) to a smaller value in the ultraviolet (UV). Describing this running in terms of deformed dispersion relations, I show that a striking cosmological implication is that that UV behavior leading to 2 spectral dimensions results in an exactly scale-invariant spectrum of vacuum scalar and tensor fluctuations. I discuss scenarios that break exact scale-invariance and show that the tensor to scalar ratio is fixed by the UV ratio between the speed of gravity and the speed of light. Cosmological perturbations in this framework display a wavelength-dependent speed of light, but by transforming to a suitable "rainbow frame" this feature can be removed, at the expense of modifying gravity. In particular it turns out that the following concepts are closely connected: scale-invariance of vacuum fluctuations, conformal invariance of the gravitational coupling, UV reduction to spectral dimension 2 in position space and UV reduction to Hausdorff dimension 2 in energy-momentum space.

Title	Date	Collection	Type	Info
Bounding the Elliptope of Quantum Correlations & Proving Separability in Mixed States	2013‑11‑26	Quantum Foundations	Scientific Series	View details
Classical Space Times from S Matrices	2013‑11‑26	Particle Physics	Scientific Series	View details
BiGravity: from Cosmological Solutions to Dual Galileons	2013‑11‑26	Cosmology and Gravitation	Scientific Series	View details
13/14 PSI - Condensed Matter - Lecture 12	2013‑11‑26	13/14 PSI - Condensed Matter	Course	View details
13/14 PSI - Quantum Field Theory II - Lecture 12	2013‑11‑26	13/14 PSI - Quantum Field Theory II	Course	View details
13/14 PSI - Condensed Matter - Lecture 11	2013‑11‑25	13/14 PSI - Condensed Matter	Course	View details
13/14 PSI - Quantum Field Theory II - Lecture 11	2013‑11‑25	13/14 PSI - Quantum Field Theory II	Course	View details
13/14 PSI - Condensed Matter - Lecture 10	2013‑11‑22	13/14 PSI - Condensed Matter	Course	View details
13/14 PSI - Quantum Field Theory II - Lecture 10	2013‑11‑22	13/14 PSI - Quantum Field Theory II	Course	View details
General Relativity for Cosmology - Lecture 20	2013‑11‑21	General Relativity for Cosmology - 2013	Course	View details
General Relativity for Cosmology - Lecture 19	2013‑11‑21	General Relativity for Cosmology - 2013	Course	View details
Dimensional reduction in the sky	2013‑11‑21	Quantum Gravity	Scientific Series	View details

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Format results

Bounding the Elliptope of Quantum Correlations & Proving Separability in Mixed States

Classical Space Times from S Matrices

BiGravity: from Cosmological Solutions to Dual Galileons

13/14 PSI - Condensed Matter - Lecture 12

13/14 PSI - Quantum Field Theory II - Lecture 12

13/14 PSI - Condensed Matter - Lecture 11

13/14 PSI - Quantum Field Theory II - Lecture 11

13/14 PSI - Condensed Matter - Lecture 10

13/14 PSI - Quantum Field Theory II - Lecture 10

General Relativity for Cosmology - Lecture 20

General Relativity for Cosmology - Lecture 19

Dimensional reduction in the sky

Bounding the Elliptope of Quantum Correlations & Proving Separability in Mixed States

Classical Space Times from S Matrices

BiGravity: from Cosmological Solutions to Dual Galileons

13/14 PSI - Condensed Matter - Lecture 12

13/14 PSI - Quantum Field Theory II - Lecture 12

13/14 PSI - Condensed Matter - Lecture 11

13/14 PSI - Quantum Field Theory II - Lecture 11

13/14 PSI - Condensed Matter - Lecture 10

13/14 PSI - Quantum Field Theory II - Lecture 10

General Relativity for Cosmology - Lecture 20

General Relativity for Cosmology - Lecture 19

Dimensional reduction in the sky