English
Related papers

Related papers: Friedmann equations from emergence of cosmic space

200 papers

The intention of our paper is to provide a pedagogical application of geometric algebra to a particularly well-investigated system: We formulate the geometric and dynamical properties of Friedmann-Robertson-Walker spacetimes within the…

General Relativity and Quantum Cosmology · Physics 2025-09-10 Pablo Banon Perez , Bjoern Malte Schaefer , Maarten DeKieviet

In this paper we present the equations of the evolution of the universe in $D$ spatial dimensions, as a generalization of the work of Lima \citep{lima}. We discuss the Friedmann-Robertson-Walker cosmological equations in $D$ spatial…

General Relativity and Quantum Cosmology · Physics 2012-07-09 R. F. L. Holanda , S. H. Pereira

Applying the first law of thermodynamics to the apparent horizon of a Friedmann-Robertson-Walker universe and assuming the geometric entropy given by a quarter of the apparent horizon area, we derive the Friedmann equations describing the…

High Energy Physics - Theory · Physics 2009-11-11 Rong-Gen Cai , Sang Pyo Kim

In this work we present a derivation of modified Raychaudhuri and Friedmann equations from a phenomenological model of quantum gravity based on the thermodynamics of spacetime. Starting from general gravitational equations of motion which…

General Relativity and Quantum Cosmology · Physics 2023-09-13 Ana Alonso-Serrano , Marek Liška , Antonio Vicente-Becerril

The main objective of this manuscript is to investigate the bouncing cosmology in the background of $f(\mathcal{Q})$ gravity, where $\mathcal{Q}$ defines the non-metricity. For this purpose, we use the reconstruction approach and consider a…

General Relativity and Quantum Cosmology · Physics 2024-04-02 M. Sharif , M. Zeeshan Gul , Nusrat Fatima

This paper explores the Friedmann field equations within the framework of Lovelock gravity, a natural extension of Einstein's gravity, focusing on both flat and open universes. Utilizing an approach based on independent Riemann tensor…

General Relativity and Quantum Cosmology · Physics 2024-12-30 Aleksei Nikolaev

The Einstein equations of general relativity reduce, when the spacetime metric is of the Friedmann--Lemaitre--Robertson--Walker type governing an isotropic and homogeneous universe, to the Friedmann equations, which is a set of nonlinear…

General Relativity and Quantum Cosmology · Physics 2024-07-30 Yisong Yang

In the paper, hep-th/0501055 (R.G. Cai and S.P. Kim, JHEP {\bf 0502}, 050 (2005)), it is shown that by applying the first law of thermodynamics to the apparent horizon of an FRW universe and assuming the geometric entropy given by a quarter…

High Energy Physics - Theory · Physics 2008-11-26 M. Akbar , Rong-Gen Cai

We study the deep connections between the concepts of quantum information theory and cosmology. Employing Fermi normal coordinates and conformal Fermi coordinates, we construct a relation between Friedmann equations of…

General Relativity and Quantum Cosmology · Physics 2018-07-12 Xian-Hui Ge , Can-Can Wang

We present a cosmological model arising from a gravitational theory with an infinite tower of higher-order curvature invariants that can reproduce the entire evolution of the Universe: from inflation to late-time acceleration, without…

General Relativity and Quantum Cosmology · Physics 2022-02-10 Luisa G. Jaime , Gustavo Arciniega

We study the potential effects of spacetime non-metricity in cosmology. In the spirit of Einstein-Cartan gravity, but with non-metricity replacing torsion, we consider the Einstein-Hilbert action and assume zero torsion. Adopting certain…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Damianos Iosifidis , Ioannis Georgios Vogiatzis , Christos G. Tsagas

The evolution of a universe with Brans-Dicke gravity and nonzero curvature is investigated here. We present the equations of motion and their solutions during the radiation dominated era. In a Friedman-Robertson-Walker cosmology we show…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Janna Levin , Katherine Freese

We consider a simplified model of quantum gravity using a mini-superspace description of an isotropic and homogeneous universe with dust. We derive the corresponding Friedmann equations for the scale factor, which now contain a dependence…

General Relativity and Quantum Cosmology · Physics 2020-04-03 Thibaut Demaerel , Christian Maes , Ward Struyve

The theoretical and observational consequences of thermodynamics of open systems, which allow particle creation are investigated in modified $f(R,T)$ ($R$ is the Ricci scalar and $T$ is the trace of energy-momentum tensor) theory of gravity…

General Relativity and Quantum Cosmology · Physics 2014-08-26 C. P. Singh , Vijay Singh

We extend the earlier linear studies of cosmological peculiar velocities to Friedmann universes with nonzero spatial curvature. In the process, we also compare our results with those obtained in cosmologies with Euclidean spatial sections.…

General Relativity and Quantum Cosmology · Physics 2024-08-28 Eleftheria P. Miliou , Christos G. Tsagas

We derive a unified expansion law for our universe from the first law of thermodynamics on the apparent horizon, where entropic evolution depicts the emergence of cosmic space. The derivation advances a general form for degrees of freedom…

General Relativity and Quantum Cosmology · Physics 2023-02-22 Hassan Basari V. T. , P. B. Krishna , Titus K. Mathew

Many studies have been carried out since T.Padmanabhan proposed that the cosmic acceleration can be understood from the perspective that spacetime dynamics is an emergent phenomenon. Motivated by such a new paradigm, we firstly study the de…

General Relativity and Quantum Cosmology · Physics 2015-08-05 Zi-Liang Wang , Wen-Yuan Ai , Hua Chen , Jian-Bo Deng

Inspired by the entropy-area relation of black hole thermodynamics, we study the thermodynamics of cosmological apparent horizon in a spatially flat Friedmann-Robertson-Walker (FRW) universe in the framework of an Extended Uncertainty…

General Relativity and Quantum Cosmology · Physics 2024-08-29 Maryam Roushan , Narges Rashidi , Kourosh Nozari

The Friedmann equation in the Friedmann-Robertson-Walker(FRW) universe with any spatial curvature is derived from the first law of thermodynamics on the event horizon. The key idea is to redefine a Hawking temperature on the event horizon.…

High Energy Physics - Theory · Physics 2016-03-08 Fei-Quan Tu , Yi-Xin Chen

Process of formation of the universe with its further expansion in the first evolution stage is investigated in the framework of Friedmann-Robertson-Walker metrics on the basis of quantum model, where a new type of matter is introduced,…

General Relativity and Quantum Cosmology · Physics 2013-01-17 Sergei P. Maydanyuk