Astrophysics

Displaying 1165 - 1176 of 2162

Rethinking Cosmology
March 06, 2013

PIRSA:13030079
Astrophysics
12/13 PSI - Cosmology Review Lecture 12

Latham Boyle University of Edinburgh
March 06, 2013

PIRSA:13030043
Astrophysics
12/13 PSI - Cosmology Review Lecture 11

Latham Boyle University of Edinburgh
March 05, 2013

PIRSA:13030042
Astrophysics
Getting the Most out of a Black Hole

Alexander Tchekhovskoy Princeton University
March 04, 2013

PIRSA:13030102
Astrophysics
12/13 PSI - Cosmology Review Lecture 10

Latham Boyle University of Edinburgh
March 04, 2013

PIRSA:13030041
Astrophysics
12/13 PSI - Cosmology Review Lecture 9

Latham Boyle University of Edinburgh
March 01, 2013

PIRSA:13030038
Astrophysics
12/13 PSI - Cosmology Review Lecture 8

Latham Boyle University of Edinburgh
February 28, 2013

PIRSA:13020108
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
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

Rethinking Cosmology
March 06, 2013

PIRSA:13030079
Astrophysics
This talk will begin by discussing one by one the various reasons why cosmologists today consider the big bang inflationary cosmology to be the leading, if not proven, theory of the universe and then explaining why each of these reasons is flawed. This leads naturally to the question: what is the alternative? Understanding the flaws helps point the way.
12/13 PSI - Cosmology Review Lecture 12

Latham Boyle University of Edinburgh
March 06, 2013

PIRSA:13030043
Astrophysics
12/13 PSI - Cosmology Review Lecture 11

Latham Boyle University of Edinburgh
March 05, 2013

PIRSA:13030042
Astrophysics
Getting the Most out of a Black Hole

Alexander Tchekhovskoy Princeton University
March 04, 2013

PIRSA:13030102
Astrophysics
As black holes accrete surrounding gas, they often produce relativistic, collimated outflows, or jets. Jets are expected to form in the black hole vicinity making them powerful probes of strong-field gravity. However, how jet properties are connected to black hole and accretion flow properties has been unclear. Recent progress in computer simulations of black hole accretion enables studies of jet formation in unprecedented detail. For the first time, 3D general relativistic magnetohydrodynamic numerical simulations allow one to determine the maximum efficiency with which accretion onto black holes can power relativistic jets. I will present the dependence of this maximum efficiency on black hole spin and discuss how this dependence allows one to probe strong-field gravity. In realistic astrophysical systems, the angular momentum vector of the accretion flow can be tilted relative to the spin of the black hole. I will present the first simulations of jets from such tilted accretion systems and discuss their observational signatures.
12/13 PSI - Cosmology Review Lecture 10

Latham Boyle University of Edinburgh
March 04, 2013

PIRSA:13030041
Astrophysics
12/13 PSI - Cosmology Review Lecture 9

Latham Boyle University of Edinburgh
March 01, 2013

PIRSA:13030038
Astrophysics
12/13 PSI - Cosmology Review Lecture 8

Latham Boyle University of Edinburgh
February 28, 2013

PIRSA:13020108
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.

Title	Speaker(s)	Date	Talk Type	Info link
Rethinking Cosmology		2013-03-06	Scientific Series	View details
12/13 PSI - Cosmology Review Lecture 12	Latham Boyle	2013-03-06	Course	View details
12/13 PSI - Cosmology Review Lecture 11	Latham Boyle	2013-03-05	Course	View details
Getting the Most out of a Black Hole	Alexander Tchekhovskoy	2013-03-04	Scientific Series	View details
12/13 PSI - Cosmology Review Lecture 10	Latham Boyle	2013-03-04	Course	View details
12/13 PSI - Cosmology Review Lecture 9	Latham Boyle	2013-03-01	Course	View details
12/13 PSI - Cosmology Review Lecture 8	Latham Boyle	2013-02-28	Course	View details
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

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Format results

Rethinking Cosmology

12/13 PSI - Cosmology Review Lecture 12

12/13 PSI - Cosmology Review Lecture 11

Getting the Most out of a Black Hole

12/13 PSI - Cosmology Review Lecture 10

12/13 PSI - Cosmology Review Lecture 9

12/13 PSI - Cosmology Review Lecture 8

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

Rethinking Cosmology

12/13 PSI - Cosmology Review Lecture 12

12/13 PSI - Cosmology Review Lecture 11

Getting the Most out of a Black Hole

12/13 PSI - Cosmology Review Lecture 10

12/13 PSI - Cosmology Review Lecture 9

12/13 PSI - Cosmology Review Lecture 8

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