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Related papers: Quantum Gravity with the Standard Model

200 papers

Amidst all candidates of physics beyond the Standard Model, string theory provides a unique proposal for incorporating gauge and gravitational interactions. In string theory, a four-dimensional theory that unifies quantum mechanics and…

High Energy Physics - Theory · Physics 2024-09-30 Fernando Marchesano , Gary Shiu , Timo Weigand

A quantum theory of gravity is described in the case of a positive cosmological constant in 3+1 dimensions. Both old and new results are described, which support the case that loop quantum gravity provides a satisfactory quantum theory of…

High Energy Physics - Theory · Physics 2007-05-23 Lee Smolin

One of the obstacles to reconciling quantum theory with general relativity, is constructing a theory which is both consistent with observation, and and gives finite answers at high energy, so that the theory holds at arbitrarily short…

High Energy Physics - Theory · Physics 2024-12-10 Andrzej Grudka , Tim R. Morris , Jonathan Oppenheim , Andrea Russo , Muhammad Sajjad

Quantum Mechanics of photons leads to a theory of Quantum Gravity that nicely matches the experimental results of varying fine structure constant,obtained from many-multiplet Quaser absorption systems and atomic clocks.The variation of that…

General Physics · Physics 2016-09-08 Pradip Kumar Chatterjee

The method of four-dimensional Causal Dynamical Triangulations provides a background-independent definition of the sum over geometries in quantum gravity, in the presence of a positive cosmological constant. We present the evidence…

High Energy Physics - Theory · Physics 2007-05-23 J. Ambjorn , J. Jurkiewicz , R. Loll

We propose several covariant models which may solve one of the problems in the cosmological constant. One of the model can be regarded as an extension of sequestering model. Other models could be regarded as extensions of the covariant…

High Energy Physics - Theory · Physics 2016-11-10 Shin'ichi Nojiri

We describe a model in which the fundamental scale M_\star of the theory which unifies gravity and quantum mechanics is in the TeV range, but without requiring additional spacetime dimensions. The weakness of gravity at low energies is due…

High Energy Physics - Phenomenology · Physics 2008-11-26 Xavier Calmet , Stephen D. H. Hsu

In a natural extension of the relativity principle we argue that a quantum theory of gravity involves two fundamental scales associated with both dynamical space-time as well as dynamical momentum space. This view of quantum gravity is…

High Energy Physics - Theory · Physics 2015-06-19 Laurent Freidel , Robert G. Leigh , Djordje Minic

A major unsolved problem in theoretical physics is to reconcile the classical theory of general relativity with quantum mechanics. These lectures will deal with an attempt to describe quantum gravity as a path integral over geometries known…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Jan Ambjorn , Jerzy Jurkiewicz , Renate Loll

Taking the quantization of electromagnetism as the paradigm, we show how this procedure cannot work for Einstein gravity. However, it does work for conformal gravity, a fourth-order derivative, renormalizable theory of gravity that Bender…

General Relativity and Quantum Cosmology · Physics 2023-01-18 Philip D. Mannheim

We presented a model for unification of electricity and gravity. We have found a consistent description of all physical quantities pertaining to the system. We have provided limiting values for all physical values. These values are neither…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. I. Arbab

Each approach to the quantum-gravity problem originates from expertise in one or another area of theoretical physics. The particle-physics perspective encourages one to attempt to reproduce in quantum gravity as much as possible of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Giovanni Amelino-Camelia

We propose a new phenomenological model for quantum gravity. This is based on a new interpretation in which quantum gravity is not an interaction, rather it is just responsible for generation of space-time-matter. Then we show this model is…

High Energy Physics - Phenomenology · Physics 2008-09-16 F. Darabi

We present a solution to the cosmological constant, the zero-point energy, and the quantum gravity problems within a single comprehensive framework. We show that in quantum theories of gravity in which the zero-point energy density of the…

High Energy Physics - Theory · Physics 2011-02-23 Philip D. Mannheim

A new approach to the cosmological constant problem is proposed by modifying Einstein's theory of general relativity, using instead a scalar-tensor theory of gravitation. This theory of gravity crucially incorporates the concept of quantum…

General Relativity and Quantum Cosmology · Physics 2011-10-28 Thomas L. Wilson

A scalar-tensor theory of gravity is formulated in which $G$ and particle masses are allowed to vary. The theory yields a globally static cosmological model with no evolutionary timescales, no cosmological coincidences, and no flatness and…

General Physics · Physics 2015-10-01 Meir Shimon

The problem of the cosmological constant appears in a new light in Unimodular Gravity. In particular, the zero momentum piece of the potential (that is, the constant piece independent of the matter fields) does not automatically produce a…

High Energy Physics - Theory · Physics 2018-02-15 Enrique Álvarez , Sergio González-Martín , Mario Herrero-Valea , Carmelo P. Martín

We use the mathematical framework of loop quantum gravity (LQG) to study the quantization of three dimensional (Riemannian) gravity with positive cosmological constant (Lambda>0). We show that the usual regularization techniques (successful…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Alejandro Perez , Daniele Pranzetti

We study four-dimensional quantum gravity using non-perturbative renormalization group methods. We solve the corresponding equations for the fully momentum-dependent propagator, Newton's coupling and the cosmological constant. For the first…

High Energy Physics - Theory · Physics 2016-02-17 Nicolai Christiansen , Benjamin Knorr , Jan M. Pawlowski , Andreas Rodigast

Quantum gravity places entirely new challenges on the formulation of a consistent theory as well as on an extraction of potentially observable effects. Quantum corrections due to the gravitational field are commonly expected to be tiny…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald