Results 31 to 40 of about 47,494 (299)
International Journal of Modern Physics D, 2012 The central object of this paper is a holonomy formulation for spin foams. Within this new representation, we analyze three general requirements: locality, composition law and cylindrical consistency. In particular, cylindrical consistency is shown to fix the arbitrary normalization of the vertex amplitude in the case of Euclidean signature.
Magliaro, Elena, Perini, Claudio
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Energies, 2021 The effects of doping manganese ions into a cerium oxide lattice for a thermochemical two-step water-splitting cycle to produce oxygen and hydrogen and new synthesis methods were experimentally investigated.
Hyun-Seok Cho +4 more
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Coarse Graining Spin Foam Quantum Gravity—A Review
Frontiers in Physics, 2020 In quantum gravity, we envision renormalization as the key tool for bridging the gap between microscopic models and observable scales. For spin foam quantum gravity, which is defined on a discretization akin to lattice gauge theories, the goal is to ...
Sebastian Steinhaus
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Invited review: The new spin foam models and quantum gravity [PDF]
Papers in Physics, 2012 In this article, we give a systematic definition of the recently introduced spin foam models for four-dimensional quantum gravity, reviewing the main results on their semiclassical limit on fixed discretizations.
Alejandro Perez
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Quantum gravity at the fifth root of unity
Physics Open, 2022 We consider quantum transition amplitudes, partition functions and observables for 3D spin foam models within SU(2)quantum group deformation symmetry, where the deformation parameter is postulated to be a complex fifth root of unity.
Marcelo Amaral +2 more
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Spin foam quantization and anomalies [PDF]
General Relativity and Gravitation, 2009 32 ...
Bojowald, Martin, Perez, Alejandro
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so(4) Plebanski Action and Relativistic Spin Foam Model [PDF]
, 1998 In this note we study the correspondence between the ``relativistic spin foam'' model introduced by Barrett, Crane and Baez and the so(4) Plebanski action.
Baez J +16 more
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Classical and Quantum Gravity, 1998 While the use of spin networks has greatly improved our understanding of the kinematical aspects of quantum gravity, the dynamical aspects remain obscure. To address this problem, we define the concept of a `spin foam' going from one spin network to another. Just as a spin network is a graph with edges labeled by representations and vertices labeled by
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Quantum Field Theory of Open Spin Networks and New Spin Foam Models [PDF]
, 2002 We describe how a spin-foam state sum model can be reformulated as a quantum field theory of spin networks, such that the Feynman diagrams of that field theory are the spin-foam amplitudes. In the case of open spin networks, we obtain a new type of state-
A. Miković +3 more
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Renormalization of Group Field Theories for Quantum Gravity: New Computations and Some Suggestions
Frontiers in Physics, 2021 We discuss motivation and goals of renormalization analyses of group field theory models of simplicial 4d quantum gravity, and review briefly the status of this research area.
Marco Finocchiaro +2 more
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