T'Hooft video talk: Conformal Gravity - BH complementarity

In summary, Gerard 't Hooft's video talk discusses the concept of conformal gravity and how it relates to black hole complementarity. He argues that if nature is fundamentally conformal, then the perception of definite size is due to a broken symmetry. He presents a model of a black hole from two different perspectives and shows how they share the same lightcone structure and differ only by a gauge transformation. 't Hooft also discusses how his ideas challenge the existence of a singularity in black holes. He references several of his published papers that provide more information on his theories.
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t'Hooft video talk: Conformal Gravity -- BH complementarity

http://pirsa.org/12050061
Conformal Gravity and Black Hole Complementarity
Speaker(s): Gerard t'Hooft
Date: 11/05/2012 - 4:40 pm
Collection: Conformal Nature of the Universe

Definitely worth watching at least some if not all of this talk. I'll try to find some published papers that relate to it. If you know of some already please post the links.
The slides and presentation are excellent though the audio level is a bit low, so it demands careful listening.

Imagine that nature is fundamentally conformal. Things have definite size for us only because that symmetry is broken by our adopting a flat world perspective. But suppose that reality has that basic symmetry. Then he models a black hole and compares two coordinatizations, from two different points of view.
A. from the standpoint of Alice outside who never sees anything fall in and only sees Hawk. rad. come out.
MH. and as witnessed by the Mad Hatter who falls in and only sees other infalling stuff and never sees anything get out.

Then he says in his conformal setup these two views of reality SHARE THE SAME LIGHTCONE structure, the same view of causality. And he calculates that these two very different views of the same reality differ only by a GAUGE TRANSFORMATION.

't Hooft's scheme of a BH seems radical to me in part because there is no singularity, as far as I can tell. I had to stop watching halfway thru the first time. Will look for some relevant papers and get back to it later today.

Does anyone who has already watched the talk have comment?
 
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These papers may give clues about how 't Hooft got to the ideas in his present talk. I'll copy the abstract of only the most recent one:

arXiv:1011.0061
The Conformal Constraint in Canonical Quantum Gravity
Gerard 't Hooft

arXiv:1009.0669
Probing the small distance structure of canonical quantum gravity using the conformal group
Gerard 't Hooft

arXiv:0909.3426
Quantum gravity without space-time singularities or horizons
Gerard 't Hooft

http://arxiv.org/abs/1011.0061
The Conformal Constraint in Canonical Quantum Gravity
Gerard 't Hooft
(Submitted on 30 Oct 2010)
Perturbative canonical quantum gravity is considered, when coupled to a renormalizable model for matter fields. It is proposed that the functional integral over the dilaton field should be disentangled from the other integrations over the metric fields. This should generate a conformally invariant theory as an intermediate result, where the conformal anomalies must be constrained to cancel out. When the residual metric is treated as a background, and if this background is taken to be flat, this leads to a novel constraint: in combination with the dilaton contributions, the matter lagrangian should have a vanishing beta function. The zeros of this beta function are isolated points in the landscape of quantum field theories, and so we arrive at a denumerable, or perhaps even finite, set of quantum theories for matter, where not only the coupling constants, but also the masses and the cosmological constant are all fixed, and computable, in terms of the Planck units.
 

FAQ: T'Hooft video talk: Conformal Gravity - BH complementarity

What is the main concept of the T'Hooft video talk on Conformal Gravity and BH complementarity?

The main concept of the T'Hooft video talk is to propose a new theory of gravity known as Conformal Gravity, which states that the laws of physics should be invariant under conformal transformations. This theory also explores the idea of black hole complementarity, which suggests that information may be able to escape a black hole in a highly distorted form.

How does Conformal Gravity differ from Einstein's Theory of General Relativity?

Unlike Einstein's Theory of General Relativity, which is based on the concept of spacetime curvature, Conformal Gravity is based on conformal transformations. This means that the laws of physics are invariant under changes in the scale of distance, but not under changes in the shape of spacetime.

What is the significance of BH complementarity in the context of black holes?

BH complementarity is significant because it suggests that the information that falls into a black hole may not be lost forever, as previously thought. Instead, it may be able to escape the black hole in a highly distorted form, which could potentially solve the information paradox of black holes.

How does T'Hooft's theory of Conformal Gravity attempt to reconcile quantum mechanics and general relativity?

T'Hooft's theory suggests that the laws of physics should be invariant under conformal transformations, which could potentially unify quantum mechanics and general relativity. This means that the theory could provide a framework for understanding how gravity behaves on a quantum level.

What are the potential implications of Conformal Gravity and BH complementarity for our understanding of the universe?

If T'Hooft's theory is proven to be correct, it could significantly advance our understanding of the universe and the fundamental laws of physics. It could also help us to better understand the behavior of black holes and potentially solve some long-standing mysteries, such as the information paradox. However, more research and experimentation is needed to fully understand the implications of this theory.

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