Results 1 to 10 of about 20,602 (71)

The volume operator in covariant quantum gravity [PDF]

, 2010
A covariant spin-foam formulation of quantum gravity has been recently developed, characterized by a kinematics which appears to match well the one of canonical loop quantum gravity.
Alexandrov S, Ashtekar A, Ashtekar A, Ashtekar A, Ashtekar A Campiglia M Henderson A, Baez J C, Barrett J W, Battisti M V Marciano A Rovelli C, Bianchi E Rovelli C Vidotto F, Carlo Rovelli, Engle J, Flori C, Flori C Thiemann T, Freidel L, Iwasaki J, Livine E, Noui K, Oriti D, Pereira R, Perez A, Reisenberger M P, Reisenberger M P, Reisenberger M P, Reisenberger M P, Rovelli C, Rovelli C, Rovelli C, Rovelli C Vidotto F, Smolin L, Thiemann T, You Ding   +30 more
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Quantum Geometry and its Implications for Black Holes [PDF]

, 2006
General relativity successfully describes space-times at scales that we can observe and probe today, but it cannot be complete as a consequence of singularity theorems.
Arnowitt R., Ashtekar A., Bojowald M., Bojowald M., Douglas M., MARTIN BOJOWALD, Nietzsche F., Vereshchagin G. V.   +7 more
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What is General Relativity? [PDF]

, 2017
General relativity is a set of physical and geometric principles, which lead to a set of (Einstein) field equations that determine the gravitational field, and to the geodesic equations that describe light propagation and the motion of particles on the ...
Coley, Alan A., Wiltshire, David L.
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The Geometry of Black Hole singularities [PDF]

, 2014
Recent results show that important singularities in General Relativity can be naturally described in terms of finite and invariant canonical geometric objects. Consequently, one can write field equations which are equivalent to Einstein's at non-singular
Stoica, Ovidiu Cristinel
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Simple quantum cosmology: Vacuum energy and initial state

, 2005
A static non-singular 10-dimensional closed Friedmann universe of Planck size, filled with a perfect fluid with an equation of state with w = -2/3, can arise spontaneously by a quantum fluctuation from nothing in 11-dimensional spacetime.
D. Spergel, D. Youm, E. Elbaz, M. Novello, M. Tegmark, S. Alexander, S. Eidelman, T. R. Mongan, T.R. Mongan   +8 more
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Numerical Approaches to Spacetime Singularities [PDF]

, 2002
This Living Review updates a previous version which its itself an update of a review article. Numerical exploration of the properties of singularities could, in principle, yield detailed understanding of their nature in physically realistic cases ...
A A Kirillov, A A Kirillov, A A Moser, A Ashtekar, A B Burd, A Bonanno, A D Rendall, A D Rendall, A D Rendall, A E Motter, A H Norton, A M Abrahams, A M Abrahams, A Ori, A Ori, A Ori, A Ori, A Ori, A P Gentle, A Taub, A Zardecki, B Grubišić, B Grubišić, B Grubišić, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, B K Berger, C Barrabès, C Gundlach, C Gundlach, C Gundlach, C Gundlach, C Gundlach, C Gundlach, C M Chambers, C M Chambers, C M Chambers, C R Evans, C W Misner, D Christodoulou, D Christodoulou, D Eardley, D Eardley, D F Chernoff, D Garfinkle, D Garfinkle, D Garfinkle, D Garfinkle, D Garfinkle, D Garfinkle, D Garfinkle, D Garfinkle, D Garfinkle, D M Eardley, D Maison, D R Brill, D S Goldwirth, D V Gal’tsov, D V Gal’tsov, D W Hobill, E E Donets, E Kasner, E Poisson, E Poisson, E Poisson, E Seidel, E W Hirschmann, E W Hirschmann, E W Hirschmann, F Echeverria, F J Tipler, F Mellor, F Mellor, F Pretorius, G F R Ellis, G Francisco, G Johnson, G Montani, G Rein, H Elst van, H Friedrich, H Iguchi, H Iguchi, H Iguchi, H Ringström, H Ringström, I M Khalatnikov, I Olabarrieta, J A Fleck, J A Isenberg, J C Niemeyer, J D Barrow, J D Barrow, J Isenberg, J Libson, J Masso, J Pullin, J Wojtkiewicz, J Yokoyama, K Ferraz, K Nakao, K P Tod, K S Thorne, L Andersson, L M Burko, L M Burko, L M Burko, L M Burko, L M Burko, L M Burko, L S Finn, M A Pelath, M Bañados, M H P M Putten van, M L Gnedin, M MacCallum, M P Ryan Jr., M P Ryan Jr., M Suzuki, M Suzuki, M W Browne, M W Choptuik, M W Choptuik, M Weaver, M Weaver, M Weaver, M Weaver, N Deruelle, N J Cornish, N J Cornish, O Iguchi, P Anninos, P Anninos, P Bizoń, P Bizoń, P Bizoń, P Bizoń, P Breitenlohner, P Breitenlohner, P Breitenlohner, P Halpern, P Hübner, P Hübner, P K-H Ma, P R Brady, P R Brady, P R Brady, P R Brady, P R Brady, P R Brady, P T Chrusciel, P T Chruściel, R Bartnik, R Carretero-Gonzalez, R H Gowdy, R M Wald, R M Wald, R Ove, R Penrose, R Penrose, R S Hamadé, R S Hamadé, R Schoen, R T Jantzen, R T Jantzen, S A Teukolsky, S Chandrasekhar, S Cotsakis, S D Hern, S Droz, S E Rugh, S E Rugh, S E Rugh, S Hod, S Hod, S Hod, S Hod, S Hod, S Husa, S J Hern, S Kichenassamy, S L Liebling, S L Shapiro, S L Shapiro, S L Shapiro, S M C V Gonçalves, S W Hawking, S W Hawking, S W Hawking, T Chiba, T Chiba, T Damour, T Damour, T Harada, T Harada, T Koike, T Nakamura, T Nakamura, T Nakamura, V A Belinskii, V A Belinskii, V A Belinskii, V A Belinskii, V A Belinskii, V A Belinskii, V A Belinskii, V G LeBlanc, V G LeBlanc, V Moncrief, V Moncrief, V Moncrief, V Moncrief, W H Press, W Israel, W Israel, Z B Belanger   +232 more
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Loop Quantum Gravity: Four Recent Advances and a Dozen Frequently Asked Questions

, 2007
As per organizers' request, my talk at the 11th Marcel Grossmann Conference consisted of two parts. In the first, I illustrated recent advances in loop quantum gravity through examples.
Ashtekar, Abhay
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Covariant action for bouncing cosmologies in modified Gauss-Bonnet gravity

, 2019
Cyclic universes with bouncing solutions are candidates for solving the big bang initial singularity problem. Here we seek bouncing solutions in a modified Gauss-Bonnet gravity theory, of the type $R+f(G)$, where $R$ is the Ricci scalar, $G$ is the Gauss-
Lemos, José P. S., Terrucha, Inês, Vernieri, Daniele   +2 more
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Switching internal times and a new perspective on the 'wave function of the universe'

, 2019
Despite its importance in general relativity, a quantum notion of general covariance has not yet been established in quantum gravity and cosmology, where, given the a priori absence of coordinates, it is necessary to replace classical frames with ...
Hoehn, Philipp A
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Loop quantum gravity corrections to gravitational wave dispersion [PDF]

, 1997
Cosmological tensor perturbations equations are derived for Hamiltonian cosmology based on Ashtekar's formulation of general relativity, including typical quantum gravity effects in the Hamiltonian constraint as they are expected from loop quantum ...
Bojowald, Martin, Hossain, Golam Mortuza
core   +3 more sources