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Related papers: Quantum Loops in Non-Local Gravity

200 papers

In this paper the non-local finite quantum-gravity framework is incorporated into the Complex non-Riemannian Holomorphic Unified Field Theory formulated on a complexified four-dimensional manifold. By introducing entire-function regulators…

General Physics · Physics 2025-07-22 J. W. Moffat , E. J. Thompson

We study perturbative noncommutative quantum gravity by expanding the gravitational field about a fixed classical background. A calculation of the one loop gravitational self-energy graph reveals that only the non-planar graviton loops are…

High Energy Physics - Theory · Physics 2009-10-31 J. W. Moffat

This study employs the effective field theory approach to quantum gravity to investigate a non-Abelian gauge theory involving scalar particles coupled to gravity. The study demonstrates explicitly that the Slavnov-Taylor identities are…

High Energy Physics - Theory · Physics 2023-06-14 Huan Souza , L. Ibiapina Bevilaqua , A. C. Lehum

In this paper we study the most general covariant action of gravity up to terms that are quadratic in curvature. In particular this includes non-local, infinite derivative theories of gravity which are ghost-free and exhibit asymptotic…

High Energy Physics - Theory · Physics 2015-06-16 Tirthabir Biswas , Aindriú Conroy , Alexey S. Koshelev , Anupam Mazumdar

We investigate the relationship between nonlocal and local quantum field theories, and search for a viable notion of "local limit" to relate the unitary models. In Euclidean space it is relatively easy to have nonlocal theories with…

High Energy Physics - Theory · Physics 2025-09-17 Damiano Anselmi

This series of lectures gives a simple and self-contained introduction to the non-perturbative and background independent loop approach of canonical quantum gravity. The Hilbert space of kinematical quantum states is constructed and a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcus Gaul , Carlo Rovelli

String field theory motivated infinite-derivative models lead to non-local gravity modifications which form a promising class of quantum gravity candidates. In this paper we investigate effects of non-locality on the three-point function…

General Relativity and Quantum Cosmology · Physics 2025-08-07 Alexey S. Koshelev , Abhishek Naskar

We investigate the non-perturbative degrees of freedom in the class of non-local Higgs theories that have been proposed as an ultraviolet completion 4-D Quantum Field Theory (QFT) generalizing the kinetic energy operators to an infinite…

High Energy Physics - Theory · Physics 2021-09-15 Marco Frasca , Anish Ghoshal

We construct a fully covariant theory of massive gravity which does not require the introduction of an external reference metric, and overcomes the usual problems of massive gravity theories (fatal ghosts instabilities, acausality and/or…

High Energy Physics - Theory · Physics 2015-06-15 Maud Jaccard , Michele Maggiore , Ermis Mitsou

A calculation of the one loop gravitational self-energy graph in non-anticommutative quantum gravity reveals that graviton loops are damped by internal momentum dependent factors in the modified propagator and the vertex functions. The…

High Energy Physics - Theory · Physics 2016-03-29 J. W. Moffat

A nonlocal quantum gravity theory is presented which is finite and unitary to all orders of perturbation theory. Vertex form factors in Feynman diagrams involving gravitons suppress graviton and matter vacuum fluctuation loops by…

High Energy Physics - Theory · Physics 2007-05-23 J. W. Moffat

A nonlocal quantum gravity theory is presented which is finite and unitary to all orders of perturbation theory. Vertex form factors in Feynman diagrams involving gravitons suppress graviton and matter vacuum fluctuation loops by…

High Energy Physics - Theory · Physics 2011-08-17 J. W. Moffat

We study two--loop renormalization in $(2+\epsilon)$--dimensional quantum gravity. As a first step towards the full calculation, we concentrate on the divergences which are proportional to the number of matter fields. We calculate the…

High Energy Physics - Theory · Physics 2016-09-06 Toshiaki Aida , Yoshihisa Kitazawa , Jun Nishimura , Asato Tsuchiya

We derive a spacetime formulation of quantum general relativity from (hamiltonian) loop quantum gravity. In particular, we study the quantum propagator that evolves the 3-geometry in proper time. We show that the perturbation expansion of…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Michael P Reisenberger , Carlo Rovelli

We generalize the scale invariant gravity by allowing a negative kinetic energy term for the classical scalar field. This gives birth to a new scalar-tensor theory of gravity, in which the scalar field is in fact an auxiliary field. For a…

High Energy Physics - Theory · Physics 2007-05-23 Shih-Yuin Lin , Kin-Wang Ng

We study the one-loop effective action for gravity in a cosmological setup to determine possible cosmological effects of quantum corrections to Einstein theory. By considering the effect of the universal non-local terms in a toy model, we…

General Relativity and Quantum Cosmology · Physics 2009-11-11 D. Espriu , T. Multamaki , E. C. Vagenas

The recent classical nonlocal generalization of Einstein's theory of gravitation is presented within the framework of general relativity via the introduction of a preferred frame field. The nonlocal generalization of Einstein's field…

General Relativity and Quantum Cosmology · Physics 2015-06-22 B. Mashhoon

Metric theories of gravity are studied, beginning with a general action that is quadratic in curvature and allows infinite inverse powers of the d'Alembertian operator, resulting in infrared non-local extensions of general relativity. The…

High Energy Physics - Theory · Physics 2015-06-22 Aindriu Conroy , Tomi Koivisto , Anupam Mazumdar , Ali Teimouri

The path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories of volume transitions is discussed, with particular but non-exclusive reference to loop quantum cosmology. Exploiting the analogy with…

General Relativity and Quantum Cosmology · Physics 2011-07-08 Gianluca Calcagni , Steffen Gielen , Daniele Oriti

A recent proposal for gauge-invariant observables in inflation [R. Brunetti et al., JHEP 1608 (2016) 032] is examined. We give a generalisation of their construction to general background spacetimes. In flat space, we calculate one-loop…

General Relativity and Quantum Cosmology · Physics 2018-02-02 Markus B. Fröb