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Related papers: Exploring the Nature of Gravity

200 papers

The relationship between the intrinsic motion of gravity, light, and time is explored in terms of the principles of entropy, causality, energy, and symmetry conservation. A conceptual mechanism for gravity and the gravitational connection…

General Relativity and Quantum Cosmology · Physics 2009-07-02 John A. Gowan

Research during the last one decade or so suggests that the gravitational field equations in a large class of theories (including, but not limited to, general relativity) have the same status as the equations of, say, gas dynamics or…

General Relativity and Quantum Cosmology · Physics 2015-06-23 T. Padmanabhan

We show that, when we study the coexistence of general relativity with thermodynamics, some physical properties that are usually thought of as holographic and lying in the domain of quantum gravity can actually be accessed even at the…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Ntina Savvidou , C. Anastopoulos

Renewed interest in deriving gravity (more precisely, the Einstein equations) from thermodynamics considerations [1, 2] is stirred up by a recent proposal that 'gravity is an entropic force' [3] (see also [4]). Even though I find the…

General Relativity and Quantum Cosmology · Physics 2011-05-25 B. L. Hu

Gravity is derived from an entropic action coupling matter fields with geometry. The fundamental idea is to relate the metric of Lorentzian spacetime to a quantum operator, playing the role of an renormalizable effective density matrix and…

General Relativity and Quantum Cosmology · Physics 2025-03-20 Ginestra Bianconi

The connection between gravity and thermodynamics is explored. Examining a perfect fluid in gravitational equilibrium we find that the entropy is extremal only if Einstein's equations are satisfied. Conversely, one can derive part of…

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

The Einstein-Hilbert action (and thus the dynamics of gravity) can be obtained by combining the principle of equivalence, special relativity and quantum theory in the Rindler frame and postulating that the horizon area must be proportional…

General Relativity and Quantum Cosmology · Physics 2009-11-07 T. Padmanabhan

We generalize the $f(R)$ type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$ and of the matter Lagrangian $L_m$. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-02-09 Tiberiu Harko , Francisco S. N. Lobo

We develop a formulation of global thermodynamics for equilibrium systems under the influence of gravity. The free energy for simple fluids is extended to include a dependence on $(T, V, N, mgL)$, where $L$ represents the vertical system…

Statistical Mechanics · Physics 2025-06-26 Naoko Nakagawa , Shin-ichi Sasa , Takamichi Hirao , Tsuyoshi Shiina , Kyosuke Tachi , Akira Yoshida

We consider the formulation of entropic gravity in two spacetime dimensions. The usual gravitational force law is derived even in the absence of area, as normally required by the holographic principle. A special feature of this perspective…

High Energy Physics - Theory · Physics 2011-08-31 R. B. Mann , J. R. Mureika

In this paper, we shall consider $f(R)$ gravity and its cosmological implications, when an extra matter term generated by thermal effects is added by hand in the Lagrangian. We formulate the equations of motion of the theory as a dynamical…

General Relativity and Quantum Cosmology · Physics 2020-09-29 V. K. Oikonomou , F. P. Fronimos , N. Th. Chatzarakis

The Einstein-Hilbert Lagrangian has no well-defined variational derivative with respect to the metric. This issue has to be tackled by adding a suitable surface term to the action, which is a peculiar feature of gravity. We also know that…

General Relativity and Quantum Cosmology · Physics 2020-03-18 Sumanta Chakraborty , T. Padmanabhan

This research is aimed at the revision of the thermodynamic concepts and their relationship with the General Relativity Theory (GRT) and how physical systems are affected when gravity is included in their thermodynamic description. We found…

General Relativity and Quantum Cosmology · Physics 2013-07-25 W. A. Rojas C. , R. Arenas S

By following the general guiding principle that nothing should be prescribed or imposed on the universal entity, spacetime, we establish that it is the homogeneity (by which we mean homogeneity and isotropy of space and homogeneity of time)…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Naresh Dadhich

We study the scalar-tensor theory of gravity profoundly in the action level as well as in the thermodynamic level. Contrary to the usual description in the literature about the equivalence in the two conformally connected frames, this paper…

General Relativity and Quantum Cosmology · Physics 2017-05-19 Krishnakanta Bhattacharya , Bibhas Ranjan Majhi

Some highly speculative and serendipitous ideas that might relate thermodynamics, spacetime, shape and symmetry are brought together. A hypothetical spacetime comprising a pointwise lattice with a fixed metric is considered. If there were…

General Physics · Physics 2007-10-08 Jim McGovern

In this paper we show how a gravitational field generated by a given energy-momentum distribution (for all realistic cases) can be represented by distinct geometrical structures (Lorentzian, teleparallel and non null nonmetricity…

Mathematical Physics · Physics 2012-07-03 Waldyr A. Rodrigues

We show that it is possible to obtain a picture of equilibrium thermodynamics on the apparent horizon in the expanding cosmological background for a wide class of modified gravity theories with the Lagrangian density $f(R, \phi, X)$, where…

General Relativity and Quantum Cosmology · Physics 2010-10-12 Kazuharu Bamba , Chao-Qiang Geng , Shinji Tsujikawa

Theories of emergent gravity have established a deep connection between entropy and the geometry of spacetime by looking at the latter through a thermodynamic lens. In this framework, the macroscopic properties of gravity arise in a…

General Relativity and Quantum Cosmology · Physics 2025-12-01 Valeria Rossi , Sergio Luigi Cacciatori , Alessandro Pesci

A new gauge theory of gravity is presented. The theory is constructed in a flat background spacetime and employs gauge fields to ensure that all relations between physical quantities are independent of the positions and orientations of the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Anthony Lasenby , Chris Doran , Stephen Gull