Lorentz symmetry: Broken, intact or deformed? Speaker(s): Niayesh Afshordi, David Mattingly, Rafael Sorkin, Sabine Hossenfelder, Jurek Kowalski-Glikman, Stefano Liberati, Joao Magueijo, Daniel Sudarsky
Abstract: Is aether technically natural?
I will discuss whether higher energy Lorentz violation should be considered a natural expectation in theories of quantum gravity with a preferred frame. _____________________________ If ... read more Date: 24/10/2012 - 3:30 pm
Collection: Experimental Search for Quantum Gravity 2012
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Photons and Quantum Gravity in Astrophysics Speaker(s): Alfio Bonanno, Robert Brandenberger, Joao Magueijo, Robert Nemiroff, Niayesh Afshordi, Giovanni Amelino-Camelia
Abstract: Asymptotically safe inflation and CMB polarization
The presence of complex critical exponents in the scaling behavior of the Newton constant and Cosmological constant has dramatic consequences at the inflation scale. In particular an infinite... read more Date: 22/10/2012 - 4:30 pm
Collection: Experimental Search for Quantum Gravity 2012
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Is Nothing Sacred? The Cosmological Pay Off from Breaking Lorentz and Diffeormorphism Invariance Speaker(s): Joao Magueijo
Abstract: I show how the local Lorentz and/or diffeomorphism invariances may be broken by a varying c, softly or harshly, depending on taste. Regardless of the fundamental implications of such dramas, these symmetry breakings may be of great practical use in cosmology. They may solve the horizon and... read more
Date: 11/05/2012 - 2:30 pm
Collection: Conformal Nature of the Universe - 2012
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PIRSA:11090067
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Cosmology Meets Quantum Gravity: a Chiral Signature in the CMB? Speaker(s): Joao Magueijo
Abstract: Cosmology and quantum gravity have not always had the smoothest of interactions. As a case in point I'll summarize the calculation behind the prediction of tensor modes in inflationary universes and discuss the difficulties found in recasting this calculation in terms of Ashtekar-Barbero-Immirzi var... read more
Date: 08/09/2011 - 4:00 pm
Series: Quantum Gravity
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PIRSA:09090011
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Generating scale-invariant fluctuations without inflation Speaker(s): Joao Magueijo
Abstract: I describe a number of techniques that allow for the generation of (near) scale-invariant fluctuations in the early Universe without inflation or ekpyrosis. The basic ingredient is a decaying maximal speed of propagation, for which a Universal law is found. Connections are made with k-essence, the c... read more
Date: 24/09/2009 - 3:00 pm
Series: Cosmology & Gravitation
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PIRSA:07080028
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Cosmic Microwave Background and the Structure of the Universe Speaker(s): Joao Magueijo
Abstract:
Date: 15/08/2007 - 9:00 am
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PIRSA:07080026
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Cosmic Microwave Background and the Structure of the Universe Speaker(s): Joao Magueijo
Abstract:
Date: 14/08/2007 - 11:00 am
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PIRSA:07080022
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Cosmic Microwave Background and the Structure of hte Universe Speaker(s): Joao Magueijo
Abstract:
Date: 13/08/2007 - 11:00 am
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PIRSA:06060057
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Faster than the Speed of Light - Could the laws of physics change? Speaker(s): Joao Magueijo
Abstract: The laws of physics are usually meant to be set in stone; variability is not usually part of physics. Yet contradicting Einstein's tenet of the constancy of the speed of light raises nothing less than that possibility. I will discuss some of the more dramatic implications of a varying speed of light... read more
Date: 23/06/2006 - 7:00 pm
Collection: Perimeter Institute Public Lecture Series
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PIRSA:06020034
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
MOND habitats within the solar system Speaker(s): Joao Magueijo
Abstract:
Date: 21/02/2006 - 11:00 am
Series: Cosmology & Gravitation
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PIRSA:05100033
( Flash Presentation , Windows Presentation , Windows Video File , MP3 , PDF) Which Format?
Faster than the Speed of Light: Could the Laws of Physics Change? Speaker(s): Joao Magueijo
Abstract: Could the laws of physics change? The laws of physics are usually meant to be set in stone; variability is not usually part of physics. Yet contradicting Einstein's tenet of the constancy of the speed of light raises nothing less than that possibility. I will discuss some of the more dramatic implic... read more
Date: 22/10/2005 - 2:00 pm
Collection: EinsteinFest - 2005
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