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A Nearly Gaussian Hubble-patch in a non-Gaussian Universe

Marilena LoVerde University of Washington
October 08, 2013

PIRSA:13100076
Cosmology
13/14 PSI - Statistical Mechanics - Lecture 2

Anton Burkov University of Waterloo

October 08, 2013

PIRSA:13100040
Geometry and Topology in the Fractional Quantum Hall Effect

Duncan Haldane Princeton University
October 07, 2013

PIRSA:13100086
Condensed Matter
13/14 PSI - Quantum Field Theory I - Lecture 1

Freddy Cachazo Perimeter Institute for Theoretical Physics

October 07, 2013

PIRSA:13100020
13/14 PSI - Statistical Mechanics - Lecture 1

Anton Burkov University of Waterloo

October 07, 2013

PIRSA:13100039
Topics in QFT on Flat and Curved Spacetimes - Lecture 5

Ugo Moschella University of Insubria

October 07, 2013

PIRSA:13100011
How Different the Classrooms of 2030?

Steve Paikin TVO

October 04, 2013

PIRSA:13100095
Screens Instead of Books

Steve Paikin TVO

October 03, 2013

PIRSA:13100094
Presentation of the Equinox Communiqué and Closing Remarks

October 03, 2013

PIRSA:13100093
Learning 2030: Scientific Literacy for All

Steve Paikin TVO

October 02, 2013

PIRSA:13100092
Alan Turing and the Enigma Machine

James Grime University of Cambridge

October 02, 2013

PIRSA:13100079
Topics in QFT on Flat and Curved Spacetimes - Lecture 4

Ugo Moschella University of Insubria

October 02, 2013

PIRSA:13100015

A Nearly Gaussian Hubble-patch in a non-Gaussian Universe

Marilena LoVerde University of Washington
October 08, 2013

PIRSA:13100076
Cosmology
Local-type primordial non-Gaussianity couples statistics of the curvature perturbation \zeta on vastly different physical scales. Because of this coupling, statistics (i.e. the polyspectra) of \zeta in our Hubble volume may not be representative of those in the larger universe -- that is, they may be biased. The bias depends on the local background value of \zeta, which includes contributions from all modes with wavelength k ~< H_0 and is therefore enhanced if the entire post-inflationary patch is large compared with our Hubble volume. I will discuss the bias to locally-measured statistics for general local-type non-Gaussianity. I will discuss three examples in detail: (i) the usual fNL, gNL model, (ii) a strongly non-Gaussian model with \zeta ~ \zeta_G^p, and (iii) two-field non-Gaussian initial conditions. In each scenario one may generate statistics in a Hubble-size patch that are weakly Gaussian and consistent with observations despite the fact that the statistics in the larger, post-inflationary patch look very different. Finally, I will present a worked example of how the variation in local statistics arises in the curvaton scenario.
13/14 PSI - Statistical Mechanics - Lecture 2

Anton Burkov University of Waterloo

October 08, 2013

PIRSA:13100040
Geometry and Topology in the Fractional Quantum Hall Effect

Duncan Haldane Princeton University
October 07, 2013

PIRSA:13100086
Condensed Matter
The FQHE is exhibited by electrons moving on a 2D surface through which a magnetic flux passes, giving rise to flat bands with extensive degeneracy (Landau levels). The degeneracy of a partially-filled Landau level is lifted by Coulomb repulsion between the electrons, which at certain rational fillings, leads to gapped incompressible topologically-ordered fluid states exhibiting the FQHE. Successful model wavefunctions for FQHE states, such as the Laughlin and Moore-Read states, are surprisingly related to Euclidean conformal field theory, even though they are gapped incompressiible quantum fluids with a fundamental unit of area set by the area per magnetic flux quantum h/e. The model wavefunctions are parametrized by a continuously-variable Euclidean metric, just like the Euclidean conformal group of the cft to which they are related. This metric is fixed locally both by the form of the projected Coulomb interaction within the partially-filled Landau level, and by local gradients of the tangential electric field on the 2D surface, promoting it from a static flat metric fixed globally by the cft, to a dynamic local physical degree of freedom of the FQHE fluid with area-preserving zero-point fluctuations that leave an imprint in the ground-state structure function. The curious connection to cft appears to be that the Virasoro algebra plays a fundament role in both cft and FQHE, for apparently-unrelated reasons. In the FQHE it derives from a chiral "gravitional" (geometric) topologically-protected anomaly at the edge of the fluid that is also revealed in the entanglement spectrum of a cut through the bulk fluid.
13/14 PSI - Quantum Field Theory I - Lecture 1

Freddy Cachazo Perimeter Institute for Theoretical Physics

October 07, 2013

PIRSA:13100020
13/14 PSI - Statistical Mechanics - Lecture 1

Anton Burkov University of Waterloo

October 07, 2013

PIRSA:13100039
Topics in QFT on Flat and Curved Spacetimes - Lecture 5

Ugo Moschella University of Insubria

October 07, 2013

PIRSA:13100011
How Different the Classrooms of 2030?

Steve Paikin TVO

October 04, 2013

PIRSA:13100095

This episode of The Agenda will feature a panel discussion revealing insights around the WGSI communiqué.
Screens Instead of Books

Steve Paikin TVO

October 03, 2013

PIRSA:13100094

This episode of The Agenda will examine how our ideas about knowledge and learning will change when our classrooms switch from books to screens.
Presentation of the Equinox Communiqué and Closing Remarks

October 03, 2013

PIRSA:13100093
Learning 2030: Scientific Literacy for All

Steve Paikin TVO

October 02, 2013

PIRSA:13100092

This episode of The Agenda will examine how to teach science in a way that will allow most students to be engaged by it without the fear of failure.
Alan Turing and the Enigma Machine

James Grime University of Cambridge

October 02, 2013

PIRSA:13100079

Alan Turing was one of our great 20th century mathematicians, and a pioneer of computer science. However, he may best be remembered as one of the leading code breakers of Bletchley Park during World War II. It was Turing's brilliant insights and mathematical mind that helped to break Enigma, the apparently unbreakable code used by the German military. We present a history of both Alan Turing and the Enigma, leading up to this fascinating battle of man against machine - including a full demonstration of an original WWII Enigma Machine!
Topics in QFT on Flat and Curved Spacetimes - Lecture 4

Ugo Moschella University of Insubria

October 02, 2013

PIRSA:13100015

Title	Date	Collection	Type	Info
A Nearly Gaussian Hubble-patch in a non-Gaussian Universe	2013‑10‑08	Cosmology and Gravitation	Scientific Series	View details
13/14 PSI - Statistical Mechanics - Lecture 2	2013‑10‑08	13/14 PSI - Statistical Mechanics	Course	View details
Geometry and Topology in the Fractional Quantum Hall Effect	2013‑10‑07	Quantum Matter	Scientific Series	View details
13/14 PSI - Quantum Field Theory I - Lecture 1	2013‑10‑07	13/14 PSI - Quantum Field Theory I	Course	View details
13/14 PSI - Statistical Mechanics - Lecture 1	2013‑10‑07	13/14 PSI - Statistical Mechanics	Course	View details
Topics in QFT on Flat and Curved Spacetimes - Lecture 5	2013‑10‑07	Topics in QFT on Flat and Curved Spacetimes	Course	View details
How Different the Classrooms of 2030?	2013‑10‑04	WGSI - Equinox Summit: Education 2030	Other	View details
Screens Instead of Books	2013‑10‑03	WGSI - Equinox Summit: Education 2030	Other	View details
Presentation of the Equinox Communiqué and Closing Remarks	2013‑10‑03	WGSI - Equinox Summit: Education 2030	Other	View details
Learning 2030: Scientific Literacy for All	2013‑10‑02	WGSI - Equinox Summit: Education 2030	Other	View details
Alan Turing and the Enigma Machine	2013‑10‑02	Colloquium	Scientific Series	View details
Topics in QFT on Flat and Curved Spacetimes - Lecture 4	2013‑10‑02	Topics in QFT on Flat and Curved Spacetimes	Course	View details

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