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Related papers: Problems with Mannheim's conformal gravity program

200 papers

A description of the canonical formulation of lineal gravity minimally coupled to N point particles in a circular topology is given. The Hamiltonian is found to be equal to the time-rate of change of the extrinsic curvature multiplied by…

General Relativity and Quantum Cosmology · Physics 2009-11-07 R. B. Mann

Many structures in nature are invariant under the transformation (p,r)->(br,-p/b), where b is some scale factor. Born's reciprocity hypothesis affirms that this invariance extends to the entire Hamiltonian and equations of motion. We…

High Energy Physics - Theory · Physics 2008-12-18 Robert Delbourgo , Darrel Lashmar

We consider the gravitational correction to the running of gauge coupling. Weak gravity conjecture implies that the gauge theories break down when the gravitational correction becomes greater than the contribution from gauge theories. This…

High Energy Physics - Theory · Physics 2010-10-27 Qing-Guo Huang

We extend the systematic calculation of an approximately relativistic Hamiltonian for centre of mass and internal dynamics of an electromagnetically bound two-particle system by Sonnleitner and Barnett [1] to the case including a weak…

Quantum Physics · Physics 2019-11-27 Philip K. Schwartz , Domenico Giulini

We derive new positivity bounds at finite momentum transfer, assuming a large separation between the mass $m$ of the lightest particle in the effective theory and the mass gap $M$ to new heavy states. Massive gravity parametrically violates…

High Energy Physics - Theory · Physics 2024-02-06 Brando Bellazzini , Giulia Isabella , Sergio Ricossa , Francesco Riva

This thesis is devoted to the study of gravitational theories which can be seen as modifications or generalisations of General Relativity. The motivation for considering such theories, stemming from Cosmology, High Energy Physics and…

General Relativity and Quantum Cosmology · Physics 2011-11-10 Thomas P. Sotiriou

One of the main technical obstacles in constructing a consistent theory of quantum gravity is that the metric itself defines the causal structure required for quantization. This motivates implementing quantum aspects of gravity through an…

General Relativity and Quantum Cosmology · Physics 2025-12-16 Johas Morales , Yuri Bonder

Modifications to gravity that add additional functions of the Ricci curvature to the Einstein-Hilbert action -- collectively known as $f(R)$ theories -- have been studied in great detail. When considered as complete theories of gravity they…

Astrophysics · Physics 2009-02-20 Simon DeDeo , Dimitrios Psaltis

The incompatibility between GR and QM is generally seen as a sufficient motivation for the development of a theory of Quantum Gravity. If - so a typical argumentation - QM gives a universally valid basis for the description of all natural…

General Relativity and Quantum Cosmology · Physics 2009-02-03 Reiner Hedrich

We show that the existence of a minimum measurable length and the related Generalized Uncertainty Principle (GUP), predicted by theories of Quantum Gravity, influence all quantum Hamiltonians. Thus, they predict quantum gravity corrections…

High Energy Physics - Theory · Physics 2008-12-18 Saurya Das , Elias C. Vagenas

Theories such as massive Galileons and massive gravity can satisfy the presently known improved positivity bounds provided they are weakly coupled. We discuss the form of the EFT Lagrangian for a weakly coupled UV completion of massive…

High Energy Physics - Theory · Physics 2018-05-09 Claudia de Rham , Scott Melville , Andrew J. Tolley

Motivated by quantum mechanical considerations we earlier suggested an alternative action for discretised quantum gravity which has a dimension of length. It is the so called "linear" action. The proposed action is a "square root" of the…

High Energy Physics - Theory · Physics 2017-05-11 George Savvidy

In this lecture I address the issue of possible large distance modification of gravity and its observational consequences. Although, for the illustrative purposes we focus on a particular simple generally-covariant example, our conclusions…

High Energy Physics - Theory · Physics 2007-05-23 Gia Dvali

We calculate the one-loop divergences for quantum gravity with cosmological constant, using new parametrization of quantum metric. The conformal factor of the metric is treated as an independent variable. As a result the theory possesses an…

General Relativity and Quantum Cosmology · Physics 2011-04-12 G. de Berredo-Peixoto , A. B. Penna-Firme , I. L. Shapiro

A contribution linear in r to the gravitational potential can be created by a suitable conformal duality transformation: the conformal factor is 1/(1+r)^2 and r will be replaced by r/(1+r), where r is the Schwarzschild radial coordinate.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. -J. Schmidt

Standard approaches to quantum gravity start with a pre-spacetime structure and attempt, in accordance with Bohr's correspondence principle, to recover the pseudo-Riemannian manifold in the low energy limit. These approaches assume there is…

General Relativity and Quantum Cosmology · Physics 2011-04-26 Kaća Bradonjić

We have made a conformal gravity fit to an available sample of 110 spiral galaxies, and report here on the 20 of those galaxies whose rotation curve data points extend the furthest from galactic centers. We identify the impact on the 20…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-05 Philip D. Mannheim , James G. O'Brien

In this continuation paper, we apply the general relativistic quantum theory for one particle systems, derived in paper II of this series, to a simple problem: the quantum Schwartzchild problem, where one particle of mass {\it m% }…

Quantum Physics · Physics 2008-02-03 L. S. F. Olavo

Generic self-gravitating quantum solutions that are not critically dependent on the specifics of microscopic interactions are presented. The solutions incorporate curvature effects, are consistent with the universality of gravity, and have…

General Relativity and Quantum Cosmology · Physics 2015-05-30 James Lindesay

The postulate of universal local Weyl scaling (conformal) symmetry modifies both general relativity and the Higgs scalar field model. Conformal gravity (CG) has recently been fitted to rotation data for 138 galaxies. The conformal Higgs…

General Physics · Physics 2020-08-04 R. K. Nesbet