Results 31 to 40 of about 6,189 (307)
2D gravitational Mabuchi action on Riemann surfaces with boundaries
Journal of High Energy Physics, 2017 We study the gravitational action induced by coupling two-dimensional non-conformal, massive matter to gravity on a Riemann surface with boundaries. A small-mass expansion gives back the Liouville action in the massless limit, while the first-order mass ...
Adel Bilal, Corinne de Lacroix
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Positivity in Lorentzian Barrett–Crane models of quantum gravity [PDF]
Classical and Quantum Gravity, 2006 The Barrett-Crane models of Lorentzian quantum gravity are a family of spin foam models based on the Lorentz group. We show that for various choices of edge and face amplitudes, including the Perez-Rovelli normalization, the amplitude for every triangulated closed 4-manifold is a non-negative real number.
Cherrington, J. Wade +1 more
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Two dimensional nearly de Sitter gravity
Journal of High Energy Physics, 2021 We study some aspects of the de Sitter version of Jackiw-Teitelboim gravity. Though we do not have propagating gravitons, we have a boundary mode when we compute observables with a fixed dilaton and metric at the boundary.
Juan Maldacena +2 more
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RENORMALIZATION FOR SPIN FOAM MODELS OF QUANTUM GRAVITY [PDF]
The Tenth Marcel Grossmann Meeting, 2006 5 pages, talk given at the 10th Marcel Grossmann meeting, Rio de Janeiro, July ...
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ON INHOMOGENEITY OF A STRING BIT MODEL FOR QUANTUM GRAVITY [PDF]
International Journal of Modern Physics D, 2005 We study quantum gravitational effect on a two-dimensional open universe with one particle by means of a string bit model. We find that matter is necessarily homogeneously distributed if the influence of the particle on the size of the universe is optimized.
Lee, C.-W. H., Mann, R. B.
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Exactly solvable models of 2D dilaton quantum gravity [PDF]
Physics Letters B, 1992 We study canonical quantization of a class of 2d dilaton gravity models, which contains the model proposed by Callan, Giddings, Harvey and Strominger. A set of non-canonical phase space variables is found, forming an $SL(2,{\bf R}) \times U(1)$ current algebra, such that the constraints become quadratic in these new variables.
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Lattice Models of Quantum Gravity
, 1998 Standard Regge Calculus provides an interesting method to explore quantum gravity in a non-perturbative fashion but turns out to be a CPU-time demanding enterprise. One therefore seeks for suitable approximations which retain most of its universal features. The $Z_2$-Regge model could be such a desired simplification. Here the quadratic edge lengths $q$
Bittner, E. +5 more
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Quantum Machian time in toy models of gravity [PDF]
Classical and Quantum Gravity, 2009 27 pages, references added, typos fixed, additional comments added to abs/intro/concl, journal ref ...
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Testing a (Stringy) Model of Quantum Gravity [PDF]
, 2001 I discuss a specific model of space-time foam, inspired by the modern non-perturbative approach to string theory (D-branes). The model views our world as a three brane, intersecting with D-particles that represent stringy quantum gravity effects, which can be real or virtual.
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Renormalization of 3d quantum gravity from matrix models
Physics Letters B, 2004 14 pages, 3 ...
Ambjørn, Jan +2 more
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