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Related papers: A Quantum-Mechanical Mechanism for Reducing the Co…

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We propose that the solution to the cosmological vacuum energy puzzle may come from the infrared sector of the effective theory of gravity, where the impact of the trace anomaly is of upmost relevance. We proceed by introducing two…

General Relativity and Quantum Cosmology · Physics 2009-08-12 Evan C. Thomas , Federico R. Urban , Ariel R. Zhitnitsky

Coupling any interacting quantum mechanical system to gravity in one (time) dimension requires the cosmological constant to belong to the matter energy spectrum and thus to be quantised, even though the gravity sector is free of any quantum…

High Energy Physics - Theory · Physics 2007-05-23 Jan Govaerts

We provide an analytical solution to the quantum dynamics of a flat Friedmann-Lema\^itre- Robertson-Walker model with a massless scalar field in the presence of a small and positive cosmological constant, in the context of Loop Quantum…

General Relativity and Quantum Cosmology · Physics 2020-02-06 Mercedes Martín-Benito , Rita B. Neves

We consider a simple modification of the amplitude defining the dynamics of loop quantum gravity, corresponding to the introduction of the cosmological constant, and possibly related to the SL(2,C)q extension of the theory recently…

General Relativity and Quantum Cosmology · Physics 2011-05-13 Eugenio Bianchi , Thomas Krajewski , Carlo Rovelli , Francesca Vidotto

We discuss the linearization of Einstein equations in the presence of a cosmological constant, by expanding the solution for the metric around a flat Minkowski space-time. We demonstrate that one can find consistent solutions to the…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Jose Bernabeu , Catalina Espinoza , Nick E. Mavromatos

Within conventional big bang cosmology, it has proven to be very difficult to understand why today's cosmological constant is so small. In this paper, we show that a cyclic model of the universe can naturally incorporate a dynamical…

Astrophysics · Physics 2009-09-01 Paul J. Steinhardt , Neil Turok

Classical gravity coupled to a CFT$_4$ (matter) is considered. The effect of the quantum dynamics of matter on gravity is studied around maximally symmetric spaces (flat, de Sitter and Anti de Sitter). The structure of the graviton…

General Relativity and Quantum Cosmology · Physics 2023-12-11 Jewel K. Ghosh , Elias Kiritsis , Francesco Nitti , Valentin Nourry

Recent data on supernovae favor high values of the cosmological constant. Spacetimes with a cosmological constant have non-relativistic kinematics quite different from Galilean kinematics. De Sitter spacetimes, vacuum solutions of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 R. Aldrovandi , A. L. Barbosa , L. C. B. Crispino , J. G. Pereira

We consider further consequences of recently [1] revealed role of cosmological constant \Lambda as of a physical constant, along with the gravitational one to define the gravity i.e. the General Relativity and its low-energy limit. We now…

General Physics · Physics 2019-03-13 V. G. Gurzadyan , A. Stepanian

Building upon our recently established correspondence between quantum cosmology and the hydrogen atom [1], we investigate the specific sector of a negative cosmological constant ($\Lambda < 0$) in a flat FLRW universe with dust. While the…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Dipayan Mukherjee , Harkirat Singh Sahota , S. Shankaranarayanan

Dynamical systems methods are used to investigate global behavior of the spatially flat Friedmann-Robertson-Walker cosmological model in gravitational theory with a non-minimally coupled scalar field and a constant potential function. We…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Orest Hrycyna , Marek Szydlowski

A 4D-brane realization of $q$-theory has been proposed a few years ago. The present paper studies the corresponding late-time cosmology and establishes the dynamic cancellation of an initial cosmological constant and an attractor behavior…

High Energy Physics - Theory · Physics 2023-01-04 F. R. Klinkhamer

The cosmological constant induced by quantum fluctuation of the graviton on a given background is considered as a tool for building a spectrum of different geometries. In particular, we apply the method to the Schwarzschild background with…

General Relativity and Quantum Cosmology · Physics 2008-12-23 Remo Garattini

It is believed that gravity will be explained in the framework of the existing quantum theory when one succeeds in eliminating divergencies at large momenta or small distances (although the phenomenon of gravity has been observed only at…

General Relativity and Quantum Cosmology · Physics 2008-07-28 Felix Lev

In this thesis the cosmological constant is investigated from two points of view. First, we study the influence of a time-dependent cosmological constant on the late-time expansion of the universe. Thereby, we consider several combinations…

High Energy Physics - Theory · Physics 2007-05-23 Florian Bauer

It is shown that the probability distribution $P(\lambda)$ for the effective cosmological constant is sharply peaked at $\lambda=0$ in stochastic (or "fifth-time") stabilized quantum gravity. The effect is similar to the Baum-Hawking…

High Energy Physics - Theory · Physics 2009-10-22 J. Greensite

Quantization of a dust-like closed isotropic cosmological model with a cosmological constant is realized by the method of B. DeWitt \cite{1}. It is shown that such quantization leads to interesting results, in particular, to a finite…

General Relativity and Quantum Cosmology · Physics 2009-09-25 M. I. Kalinin , V. N. Melnikov

The work shows that the associated Einstein like gravity for the Klein-Gordon field shows the spontaneous emergence of the cosmological pressure tensor density (CPTD) that in the classical limit leads to the cosmological constant (CC). Even…

General Physics · Physics 2020-07-07 Piero Chiarelli

In the investigation and resolution of the cosmological constant problem the inclusion of the dynamics of quantum gravity can be a crucial step. In this work we suggest that the quantum constraints in a canonical theory of gravity can…

High Energy Physics - Theory · Physics 2013-04-23 Jan Govaerts , Simone Zonetti

Positive vacuum energy together with extra dimensions of space imply that our four-dimensional Universe is unstable, generically to decompactification of the extra dimensions. Either quantum tunneling or thermal fluctuations carry one past…

High Energy Physics - Theory · Physics 2009-11-10 Steven B. Giddings , Robert C. Myers