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We study the difference discrete variational principle in the framework of multi-parameter differential approach by regarding the forward difference as an entire geometric object in view of noncomutative differential geometry. By virtue of…

Mathematical Physics · Physics 2018-01-17 H. Y. Guo , Y. Q. Li , K. Wu , S. K. Wang

We analyze the effect induced on standard quantum field theory (in functional approach) by quantum gravity corrections to a pure classical background. In the framework of the Kucha\v{r} and Torre proposal for a gravity-matter theory…

General Relativity and Quantum Cosmology · Physics 2022-04-20 Giulia Maniccia , Giovanni Montani

We derive the 1-loop effective action of the cubic Galileon coupled to quantum-gravitational fluctuations in a background and gauge-independent manner, employing the covariant framework of DeWitt and Vilkovisky. Although the bare action…

High Energy Physics - Theory · Physics 2017-05-24 Ippocratis D. Saltas , Vincenzo Vitagliano

The gravity action on the piecewise flat Riemannian manifold is formulated using the discrete set of the nondegenerate 4$\times$4 matrices on the 3-simplices as some connection type variables. These variables are the discrete counterpart of…

General Relativity and Quantum Cosmology · Physics 2016-12-21 V. M. Khatsymovsky

We propose a first-order geometric Lagrangian for four-dimensional conformal gravity within the Cartan formulation, which yields, dynamically, the standard constraints on the fields, expected for conformal gravity. Upon imposing the…

High Energy Physics - Theory · Physics 2026-02-11 L. Andrianopoli , R. D'Auria , G. Grosso , L. Ravera

Majorana's arbitrary spin theory is considered in a hyperbolic complex representation. The underlying differential equation is embedded into the gauge field theories of Sachs and Carmeli. In particular, the approach of Sachs can serve as a…

General Physics · Physics 2014-09-16 S. Ulrych

Several quantum gravity approaches and field theory on an evolving lattice involve a discretization changing dynamics generated by evolution moves. Local evolution moves in variational discrete systems (1) are a generalization of the…

General Relativity and Quantum Cosmology · Physics 2014-10-28 Philipp A Hoehn

We study the variational principle and derivation of the field equations for different classes of teleparallel gravity theories, using both their metric-affine and covariant tetrad formulations. These theories have in common that in…

General Relativity and Quantum Cosmology · Physics 2021-04-22 Manuel Hohmann

Any canonical quantum theory can be understood to arise from the compatibility of the statistical geometry of distinguishable observations with the canonical Poisson structure of Hamiltonian dynamics. This geometric perspective offers a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Vishnu Jejjala , Djordje Minic , Chia-Hsiung Tze

We apply the ``consistent discretization'' approach to general relativity leaving the spatial slices continuous. The resulting theory is free of the diffeomorphism and Hamiltonian constraints, but one can impose the diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Rodolfo Gambini , Jorge Pullin

We consider modified gravity cosmological models that can be transformed into two-field chiral cosmological models by the conformal metric transformation. For the $R^2$ gravity model with an additional scalar field and the corresponding…

General Relativity and Quantum Cosmology · Physics 2021-11-11 Vsevolod R. Ivanov , Sergey Yu. Vernov

We investigate a variational approach to nonpotential perturbations of gradient flows of nonconvex energies in Hilbert spaces. We prove existence of solutions to elliptic-in-time regularizations of gradient flows by combining the…

Analysis of PDEs · Mathematics 2016-05-04 Stefano Melchionna

We propose that large quantum fluctuations of the conformal factor drastically modify classical general relativity at cosmological distance scales, resulting in a scale invariant phase of quantum gravity in the far infrared. We derive…

High Energy Physics - Theory · Physics 2009-10-22 I. Antoniadis , P. O. Mazur , E. Mottola

The Unification of Conformal and Fuzzy gravities with Internal Interactions is based on the following two facts. The first is that the tangent group of a curved manifold and the manifold itself do not necessarily have the same dimensions.…

General Relativity and Quantum Cosmology · Physics 2025-11-19 Gregory Patellis , Danai Roumelioti , Stelios Stefas , George Zoupanos

Conformal transformations of a Euclidean (complex) plane have some kind of completeness (sufficiency) for the solution of many mathematical and physical-mathematical problems formulated on this plane. There is no such completeness in the…

Mathematical Physics · Physics 2007-05-23 G. I. Garas'ko

We covariantly modify the Einstein-Hilbert action such that the modified action perturbatively resolves the flat rotational velocity curve of the spiral galaxies and gives rise to the Tully-Fisher relation, and dynamically generates the…

General Relativity and Quantum Cosmology · Physics 2011-02-01 Qasem Exirifard

From a previous paper where we proposed a description of general relativity within the gravito-electromagnetic limit, we propose an alternative modified gravitational theory. As in the former version, we analyze the vector and tensor…

General Relativity and Quantum Cosmology · Physics 2022-05-03 Sergio Giardino

We study the breakdown of conformal symmetry in a conformally invariant gravitational model. The symmetry breaking is introduced by defining a preferred conformal frame in terms of the large scale characteristics of the universe. In this…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. Salehi , H. R. Sepangi , F. Darabi

We analyse the dynamical properties of disformally transformed theories of gravity. We show that disformal transformation typically introduces novel degrees of freedom, equivalent to the mimetic dark matter, which possesses a Weyl-invariant…

General Relativity and Quantum Cosmology · Physics 2022-11-14 Pavel Jiroušek , Keigo Shimada , Alexander Vikman , Masahide Yamaguchi

It is well known that Einstein's equations assume a simple polynomial form in the Hamiltonian framework based on a Yang-Mills phase space. We re-examine the gravitational dynamics in this framework and show that {\em time} evolution of the…

General Relativity and Quantum Cosmology · Physics 2021-01-14 Abhay Ashtekar , Madhavan Varadarajan