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Related papers: Revisiting canonical gravity with fermions

200 papers

We consider a classical fermion and a classical scalar, propagating on two different kinds of 4-dimensional diffeomorphism breaking gravity backgrounds, and we derive the one-loop effective dispersion relation for matter, after integrating…

High Energy Physics - Phenomenology · Physics 2016-09-21 J. Alexandre , J. Leite

Vielbeins are necessary when coupling General Relativity (GR) to fermionic matter. This enhances the gauge group of GR to include local Lorentz transformations. In view of a reduced phase space formulation of quantum gravity, in this work…

General Relativity and Quantum Cosmology · Physics 2023-05-12 Thomas Thiemann

We review some recent developments in the conformal gravity theory that has been advanced as a candidate alternative to standard Einstein gravity. As a quantum theory the conformal theory is both renormalizable and unitary, with unitarity…

High Energy Physics - Theory · Physics 2015-05-27 Philip D. Mannheim

The status of multifractional theories is reviewed using comparative tables. Theoretical foundations, classical matter and gravity dynamics, cosmology and experimental constraints are summarized and the application of the multifractional…

High Energy Physics - Theory · Physics 2021-08-16 Gianluca Calcagni

We make a number of remarks on linearized gravity with cosmological constant in any dimension, which, we argue, can be useful in a quantum gravity framework. For this purpose we assume that the background space-time metric corresponds to…

General Relativity and Quantum Cosmology · Physics 2019-04-16 C. García-Quintero , A. Ortiz , J. A. Nieto

We use a canonical parametrization of twisted geometries describing the classical phase space of loop quantum gravity on a fixed graph, and establish its explicit correspondence with the associated frame bases and spinorial descriptions.…

General Relativity and Quantum Cosmology · Physics 2026-04-09 Iñaki Garay , Sergio Rodríguez-González , Raül Vera

A complete canonical formulation of general covariance makes it possible to construct new modified theories of gravity that are not of higher-curvature form, as shown here in a spherically symmetric setting. The usual uniqueness theorems…

General Relativity and Quantum Cosmology · Physics 2024-04-10 Martin Bojowald , Erick I. Duque

In a talk at the conference {\it Geometrical Foundations of Gravity at Tartu 2017}, it was suggested that the affine spacetime connection could be associated with purely fictitious forces. This leads to gravitation in a flat and smooth…

General Relativity and Quantum Cosmology · Physics 2018-09-13 Tomi Koivisto

In this work we consider the emergent origin of gravity in the framework of Hamilton-Randers theory, a theoretical framework for emergent quantum mechanics. After presenting the essential ingredients of the theory, a derivation of the weak…

General Physics · Physics 2024-10-24 Ricardo Gallego Torromé

Using quadratic spinor techniques we demonstrate that the Immirzi parameter can be expressed as ratio between scalar and pseudo-scalar contributions in the theory and can be interpreted as a measure of how Einstein gravity differs from a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Chung-Hsien Chou , Roh-Suan Tung , Hoi-Lai Yu

By considering matter as a constraint on the availability of gravitational degrees of freedom and accounting for the statistical interpretation of Rindler horizons, the freedom to construct quantum gravity theories reproducing General…

General Physics · Physics 2019-01-25 P. A. Mandrin

Some results of author's work in a non-geometrical approach to quantum gravity are reviewed here, among them: a quantum mechanism of classical gravity giving a possibility to compute the Newton constant; asymptotic freedom at short…

General Physics · Physics 2009-05-26 Michael A. Ivanov

Based on a family of indefinite unitary representations of the diffeomorphism group of an oriented smooth $4$-manifold, a manifestly covariant $4$ dimensional and non-perturbative algebraic quantum field theory formulation of gravity is…

High Energy Physics - Theory · Physics 2017-01-18 Gabor Etesi

A general argument provides the motivation to consider the Barbero--Immirzi parameter as a field. The specific form of the geometrical effective action allows to relate the value of the Barbero--Immirzi parameter to other quantum…

General Relativity and Quantum Cosmology · Physics 2009-09-02 Simone Mercuri

General Theory of Relativity and Quantum theory gives two different description of the same mother nature in the big and small scale respectively. Mathematical languages of these two theories are entirely different, one is geometric while…

General Physics · Physics 2020-05-11 Sijo K. Joseph

In this paper explore the relation between covariant and canonical approaches to quantum gravity and $BF$ theory. We will focus on the dynamical triangulation and spin-foam models, which have in common that they can be defined in terms of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Matthias Arnsdorf

Holst term represents an interesting addition to the Einstein-Cartan theory of gravity with torsion. When this term is present the contact interactions between vector and axial vector fermion currents gain an extra parity-violating…

High Energy Physics - Theory · Physics 2014-09-01 Ilya L. Shapiro , Poliane M. Teixeira

The 2D model of gravity with zweibeins $e^{a}$ and the Lorentz connection one-form $\omega^{a}_{\ b}$ as independent gravitational variables coupled to 2d massless Dirac matter is considered. It is shown that the classical equations of…

High Energy Physics - Theory · Physics 2009-10-28 S. N. Solodukhin

The Fermi-point scenario of emergent gravity has the following consequences: gravity emerges together with fermionic and bosonic matter; emergent fermionic matter consists of massless Weyl fermions; emergent bosonic matter consists of gauge…

General Relativity and Quantum Cosmology · Physics 2008-11-26 G. E. Volovik

A summary of recent work related to the calculation of loop quantum gravity induced corrections to standard particle (photons and spin 1/2 fermions) dynamics in flat space is presented. Stringent bounds upon the parameters characterizing…

High Energy Physics - Phenomenology · Physics 2017-08-23 Luis F. Urrutia