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Related papers: Cosmological Constant in LQG Vertex Amplitude

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Anthropic solutions to the cosmological constant problem require seemingly unnatural scalar field potentials with a very small slope or domain walls (branes) with a very small coupling to a four-form field. Here we introduce a class of…

High Energy Physics - Theory · Physics 2009-11-07 Gia Dvali , Alexander Vilenkin

In this paper, we explore an idea of having Newton's constant change its value depending on the curvature scale involved. Such modification leads to a particular scalar-tensor gravity theory, with the Lagrangian derived from renormalization…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-05 Andrei V. Frolov , Jun-Qi Guo

The action of the quantum mechanical volume operator, introduced in connection with a symmetric representation of the three-body problem and recently recognized to play a fundamental role in discretized quantum gravity models, can be given…

Quantum Physics · Physics 2013-10-22 Vincenzo Aquilanti , Dimitri Marinelli , Annalisa Marzuoli

Recent data point in the direction of a cosmological constant dominated universe. We investigate the role of supersymmetric QCD with N_f < N_c as a possible candidate for dynamical cosmological constant (``quintessence''). We take in full…

High Energy Physics - Phenomenology · Physics 2007-05-23 Francesca Rosati

We investigate the low energy continuum limit theory for electrons in a graphene sheet under strain. We use the quantum field theory in curved spaces to analyze the effect of the system deformations into an effective gauge field. We study…

Mesoscale and Nanoscale Physics · Physics 2015-12-15 Enrique Arias , Alexis R. Hernández , Caio Lewenkopf

The typical scalar field theory has a cosmological constant problem. We propose a generic mechanism by which this problem is avoided at tree level by embedding the theory into a larger theory. The metric and the scalar field coupling…

High Energy Physics - Phenomenology · Physics 2012-07-11 Roman V. Buniy , Thomas W. Kephart

A relativistic quantum mechanics is formulated in which all of the interactions are in the four-momentum operator and Lorentz transformations are kinematic. Interactions are introduced through vertices, which are bilinear in fermion and…

Quantum Physics · Physics 2008-12-19 William H. Klink

A five-dimensional solution to Einstein's equations coupled to a scalar field has been proposed as a partial solution to the cosmological constant problem: the effect of arbitrary vacuum energy (tension) of a 3-brane is cancelled; however,…

High Energy Physics - Theory · Physics 2014-11-18 P. Binetruy , J. M. Cline , C. Grojean

We discuss epsilon-expansion in curved spacetime for asymptotically free and asymptotically non-free theories. The esistence of stable and unstable fixed points is investigated for $f \phi^4$ and SU(2) gauge theory. It is shown that…

High Energy Physics - Theory · Physics 2009-09-17 I. H. Brevik , H. Ocampo , S. D. Odintsov

We argue that the cosmological constant is exponentially suppressed in a candidate ground state of loop quantum gravity as a nonperturbative effect of a holographic Fermi-liquid theory living on a two-dimensional spacetime. Ashtekar…

High Energy Physics - Theory · Physics 2009-02-23 Stephon H. S. Alexander , Gianluca Calcagni

In this paper, using a qualitative theory of dynamical systems, we study the stability of a unified dark matter-dark energy framework known as quartessence Chaplygin model (QCM) with three different equation-of-states within ultraviolet…

General Relativity and Quantum Cosmology · Physics 2018-09-06 Mohsen Khodadi , Kourosh Nozari , Fazlollah Hajkarim

We define `third derivative' General Relativity, by promoting the integration measure in Einstein-Hilbert action to be an arbitrary $4$-form field strength. We project out its local fluctuations by coupling it to another $4$-form field…

High Energy Physics - Theory · Physics 2022-09-21 Nemanja Kaloper

The concept of smooth deformation of Riemannian manifolds associated with the extrinsic curvature is explained and applied to the FLRW cosmology. We show that such deformation can be derived from Einstein-Hilbert-like dynamical principle…

General Relativity and Quantum Cosmology · Physics 2017-04-06 Abraao J. S. Capistrano , Luiz A. Cabral

Heisenberg's nonperturbative quantization technique is applied to the nonpertrubative quantization of gravity. An infinite set of equations for all Green's functions is obtained. An approximation is considered where: (a) the metric remains…

General Relativity and Quantum Cosmology · Physics 2014-11-07 Vladimir Dzhunushaliev

We examine the form of the cosmological constant in the loop expansion of broken maximally supersymmetric supergravity theories, and after embedding, within superstring and M-theory. Supersymmetry breaking at the TeV scale generates values…

High Energy Physics - Theory · Physics 2010-04-06 Gordon Chalmers

We investigate the perihelion shift of the planetary motion and the bending of starlight in the Schwarzschild field modified by the presence of a $\Lambda$-term plus a conical defect. This analysis generalizes an earlier result obtained by…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Wilson H. C. Freire , V. B. Bezerra , J. A. S. Lima

We propose a novel, higher-derivative, Weyl-invariant and generally-covariant theory for the cosmological constant. This theory is a mimetic construction with gauge fields playing the role of dynamical variables. These fields compose the…

General Relativity and Quantum Cosmology · Physics 2020-01-10 Katrin Hammer , Pavel Jirousek , Alexander Vikman

In this paper, a general FRW cosmological model has been constructed in $f(R,T)$ gravity reconstruction with variable cosmological constant. A number of solutions to the field equations has been generated by utilizing a form for the Hubble…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Nasr Ahmed , Sultan Z. Alamri

The problem of the physical nature and the cosmological constant genesis is discussed. This problem can't be solved in terms of the current quantum field theory which operates with Higgs and nonperturbative vacuum condensates and takes into…

Astrophysics · Physics 2007-05-23 Vladimir Burdyuzha , Olga Lalakulich , Yuri Ponomarev , Grigory Vereshkov

We discuss the fundamental constants of physics in the Standard Model and possible changes of these constants on the cosmological time scale. The Grand Unification of the strong, electromagnetic and weak interactions implies relations…

High Energy Physics - Phenomenology · Physics 2009-07-22 H. Fritzsch
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