Astrophysics

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12/13 PSI - Cosmology Review Lecture 7

Latham Boyle University of Edinburgh
February 27, 2013

PIRSA:13020107
Astrophysics
12/13 PSI - Cosmology Review Lecture 6

Latham Boyle University of Edinburgh
February 26, 2013

PIRSA:13020106
Astrophysics
Newton’s Method in Cosmology Today

Bill Harp Western University
February 26, 2013

PIRSA:13020151
Astrophysics
12/13 PSI - Cosmology Review Lecture 5

Latham Boyle University of Edinburgh
February 25, 2013

PIRSA:13020105
Astrophysics
Beyond Massive Gravity

Rachel Rosen Carnegie Mellon University
February 25, 2013

PIRSA:13020134
Astrophysics
Gamma Rays at 130 GeV and How They Might Come from Dark Matter

Andrew Frey University of Winnipeg
February 21, 2013

PIRSA:13020139
Astrophysics

General Relativity & Quantum Cosmology
12/13 PSI - Cosmology Review Lecture 3

Latham Boyle University of Edinburgh
February 21, 2013

PIRSA:13020101
Astrophysics
12/13 PSI - Cosmology Review Lecture 2

Latham Boyle University of Edinburgh
February 20, 2013

PIRSA:13020100
Astrophysics
12/13 PSI - Cosmology Review Lecture 1

Latham Boyle University of Edinburgh
February 19, 2013

PIRSA:13020099
Astrophysics
Multifield Reheating and the Fate of the Primordial Observables

Ewan Tarrant University of Nottingham
February 05, 2013

PIRSA:13020123
Astrophysics
Cosmic Tides

Ue-Li Pen University of Toronto
January 29, 2013

PIRSA:13010114
Astrophysics
Holographic description of cosmological singularity

Misha Smolkin Hebrew University of Jerusalem
January 22, 2013

PIRSA:13010111
Astrophysics

12/13 PSI - Cosmology Review Lecture 7

Latham Boyle University of Edinburgh
February 27, 2013

PIRSA:13020107
Astrophysics
12/13 PSI - Cosmology Review Lecture 6

Latham Boyle University of Edinburgh
February 26, 2013

PIRSA:13020106
Astrophysics
Newton’s Method in Cosmology Today

Bill Harp Western University
February 26, 2013

PIRSA:13020151
Astrophysics
Newton’s inferences from phenomena realize an ideal of empirical success that’s richer than prediction. To realize Newton’s richer conception of empirical success a theory needs to do more than to accurately predict the phenomena it purports to explain: in addition it needs to have the phenomena accurately measure parameters of the theory. Newton’s method aims to turn theoretical questions into ones which can be empirically answered by measurements from phenomena. Propositions inferred from phenomena are provisionally accepted as guides to further research. Newton’s ideal of empirical success as agreeing measurements from diverse phenomena is appealed to in support of the radical inference to dark energy in cosmology today. Robert Kirshner (two of his PhDs share one half of 2011’s Nobel Prize in physics) gave an account of the role of cosmic microwave background measurements, to back up the supernova measurements and measurements from galaxy clustering in supporting the transition of dark energy from a wild hypothesis into an accepted background assumption that guides further research in cosmology today. This illustrates a feature of agreeing measurements from diverse phenomena that is especially important for turning data into evidence. To the extent that the sources of systematic error of the different measurements can be regarded as independent, their agreement contributes additional support for counting them as accurate rather than as mere artifacts of systematic error.
12/13 PSI - Cosmology Review Lecture 5

Latham Boyle University of Edinburgh
February 25, 2013

PIRSA:13020105
Astrophysics
Beyond Massive Gravity

Rachel Rosen Carnegie Mellon University
February 25, 2013

PIRSA:13020134
Astrophysics
In the last few years there has been a burst of progress in the field of massive gravity. The construction of consistent theories in which the graviton has a small mass has in turn led to the development a new family of compelling, consistent low-energy modifications of General Relativity. These theories improve our understanding of the interplay between gravity and particle physics and provide new approaches to solving the cosmological constant problem. In this talk I will review these recent developments. I will discuss the search among these new theories for a symmetry that has the potential to address the cosmological constant problem.
Gamma Rays at 130 GeV and How They Might Come from Dark Matter

Andrew Frey University of Winnipeg
February 21, 2013

PIRSA:13020139
Astrophysics

General Relativity & Quantum Cosmology
Gamma Rays at 130 GeV and How They Might Come from Dark Matter" I'll discuss the exciting (but somewhat controversial) new discovery of a sharp gamma ray feature at 130 GeV from near the galactic center and review some other evidence that might link it to annihilation of dark matter. I will then explain the challenges in understanding how dark matter might produce this signal and explain a model or two that overcome these difficulties.
12/13 PSI - Cosmology Review Lecture 3

Latham Boyle University of Edinburgh
February 21, 2013

PIRSA:13020101
Astrophysics
12/13 PSI - Cosmology Review Lecture 2

Latham Boyle University of Edinburgh
February 20, 2013

PIRSA:13020100
Astrophysics
12/13 PSI - Cosmology Review Lecture 1

Latham Boyle University of Edinburgh
February 19, 2013

PIRSA:13020099
Astrophysics
Multifield Reheating and the Fate of the Primordial Observables

Ewan Tarrant University of Nottingham
February 05, 2013

PIRSA:13020123
Astrophysics
The presence of additional light fields during inflation can source isocurvature fluctuations, which can cause the curvature perturbation $\zeta$, and its statistics to evolve on superhorizon scales. I will demonstrate that if these fluctuations have not completely decayed before the onset of perturbative reheating, then primordial observables such as the level of non--Gaussianity can develop substantial reheating dependant corrections. I will argue that for inflationary models where an adiabatic condition is not reached before the relevant fields begin to decay, we must be careful in our interpretation of any observational constraints that place bounds on the statistics of $\zeta$.
Cosmic Tides

Ue-Li Pen University of Toronto
January 29, 2013

PIRSA:13010114
Astrophysics
We apply CMB lensing techniques to large scale structure and solve for the 3-D cosmic tidal field. We use small scale filamentary structures to solve for the large scale tidal shear and gravitational potential. By comparing this to the redshift space density field, one can measure the gravitational growth factor on large scales without cosmic variance. This potentially enables accurate measurements of neutrino masses and reconstruction of radial modes lost in 21 cm intensity mapping, which are essential for CMB and other cross correlations. We relate the tidal fields to the squeezed limit bispectrum, and present initial results from simulations and data from the SDSS.
Holographic description of cosmological singularity

Misha Smolkin Hebrew University of Jerusalem
January 22, 2013

PIRSA:13010111
Astrophysics
In my talk I will discuss our recent paper hep-th/1211.1322 where we construct a 3D conformal field theory dual to asymptotically AdS cosmology in four dimensions. Due to the scale invariance this dual theory allows an infinite family of instantons each of which breaks the conformal group O(3,2) down to O(3,1). These instantons are dual to bulk instantons responsible for nucleating an O(3,1) invariant cosmological bubble. Presumably they indicate an infinite instability rate, however we are able to sum over all of them completely. The resulting theory is manifestly stable, unitary and finite.

Title	Speaker(s)	Date	Talk Type	Info link
12/13 PSI - Cosmology Review Lecture 7	Latham Boyle	2013-02-27	Course	View details
12/13 PSI - Cosmology Review Lecture 6	Latham Boyle	2013-02-26	Course	View details
Newton’s Method in Cosmology Today	Bill Harp	2013-02-26	Scientific Series	View details
12/13 PSI - Cosmology Review Lecture 5	Latham Boyle	2013-02-25	Course	View details
Beyond Massive Gravity	Rachel Rosen	2013-02-25	Scientific Series	View details
Gamma Rays at 130 GeV and How They Might Come from Dark Matter	Andrew Frey	2013-02-21	Scientific Series	View details
12/13 PSI - Cosmology Review Lecture 3	Latham Boyle	2013-02-21	Course	View details
12/13 PSI - Cosmology Review Lecture 2	Latham Boyle	2013-02-20	Course	View details
12/13 PSI - Cosmology Review Lecture 1	Latham Boyle	2013-02-19	Course	View details
Multifield Reheating and the Fate of the Primordial Observables	Ewan Tarrant	2013-02-05	Scientific Series	View details
Cosmic Tides	Ue-Li Pen	2013-01-29	Scientific Series	View details
Holographic description of cosmological singularity	Misha Smolkin	2013-01-22	Scientific Series	View details

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Format results

12/13 PSI - Cosmology Review Lecture 7

12/13 PSI - Cosmology Review Lecture 6

Newton’s Method in Cosmology Today

12/13 PSI - Cosmology Review Lecture 5

Beyond Massive Gravity

Gamma Rays at 130 GeV and How They Might Come from Dark Matter

12/13 PSI - Cosmology Review Lecture 3

12/13 PSI - Cosmology Review Lecture 2

12/13 PSI - Cosmology Review Lecture 1

Multifield Reheating and the Fate of the Primordial Observables

Cosmic Tides

Holographic description of cosmological singularity

12/13 PSI - Cosmology Review Lecture 7

12/13 PSI - Cosmology Review Lecture 6

Newton’s Method in Cosmology Today

12/13 PSI - Cosmology Review Lecture 5

Beyond Massive Gravity

Gamma Rays at 130 GeV and How They Might Come from Dark Matter

12/13 PSI - Cosmology Review Lecture 3

12/13 PSI - Cosmology Review Lecture 2

12/13 PSI - Cosmology Review Lecture 1

Multifield Reheating and the Fate of the Primordial Observables

Cosmic Tides

Holographic description of cosmological singularity