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Journal articles on the topic 'Einstein static universe'

Author: Grafiati

Published: 10 March 2023

Last updated: 31 July 2025

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1

Atazadeh, K., and F. Darabi. "Einstein static universe from GUP." Physics of the Dark Universe 16 (June 2017): 87–93. http://dx.doi.org/10.1016/j.dark.2017.04.008.

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2

Huang, Qihong, He Huang, Bing Xu, and Kaituo Zhang. "Evolution of the Early Universe in Einstein–Cartan Theory." Universe 11, no. 5 (2025): 147. https://doi.org/10.3390/universe11050147.

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Einstein–Cartan theory is a generalization of general relativity that introduces spacetime torsion. In this paper, we perform phase space analysis to investigate the evolution of the early universe in Einstein–Cartan theory. By studying the stability of critical points in the dynamical system, we find that there exist two stable critical points which represent an Einstein static solution and an expanding solution, respectively. After analyzing the phase diagram of the dynamical system, we find that the early universe may exhibit an Einstein static state, an oscillating state, or a bouncing sta

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3

Darabi, F., Y. Heydarzade, and F. Hajkarim. "Stability of Einstein static universe over Lyra geometry." Canadian Journal of Physics 93, no. 12 (2015): 1566–70. http://dx.doi.org/10.1139/cjp-2015-0312.

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The existence and stability conditions of Einstein static universe against homogeneous scalar perturbations in the context of Lyra geometry is investigated. The stability condition is obtained in terms of the constant equation of state parameter ω = p/ρ depending on energy density ρ0 and scale factor a0 of the initial Einstein static universe. Also, the stability against vector and tensor perturbations is studied. It is shown that a stable Einstein static universe can be found in the context of Lyra geometry against scalar, vector, and tensor perturbations for suitable range and values of phys

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4

Atazadeh, K., Y. Heydarzade, and F. Darabi. "Einstein static universe in braneworld scenario." Physics Letters B 732 (May 2014): 223–27. http://dx.doi.org/10.1016/j.physletb.2014.03.009.

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5

Sharif, M., and Sana Saleem. "Stability of anisotropic perturbed Einstein universe in f(R) gravity." Modern Physics Letters A 35, no. 18 (2020): 2050152. http://dx.doi.org/10.1142/s0217732320501527.

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The aim of this paper is to investigate the existence of stable modes of the Einstein static universe in the background of [Formula: see text] theory. For this purpose, we take homogeneous anisotropic perturbations in scale factors as well as matter contents. We construct static and perturbed field equations that are further parameterized by linear equation of state parameter. We obtain the Einstein static solutions for two specific [Formula: see text] models and graphically analyze their stable regions. It is concluded that contrary to general relativity, there exists stable Einstein static u

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6

Huang, Qihong, Kaituo Zhang, He Huang, Bing Xu, and Feiquan Tu. "CMB Power Spectrum in the Emergent Universe with K-Essence." Universe 9, no. 5 (2023): 221. http://dx.doi.org/10.3390/universe9050221.

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The emergent universe provides a possible method to avoid the Big Bang singularity by considering that the universe stems from a stable Einstein static universe rather than the singularity. Since the Einstein static universe exists before inflation, it may leave some relics in the CMB power spectrum. In this paper, we analyze the stability condition for the Einstein static universe in general relativity with k-essence against both the scalar and tensor perturbations. Furthermore, we find the emergent universe can be successfully realized by constructing a scalar potential and an equation of st

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7

Atazadeh, K. "Stability of the Einstein static universe in Einstein-Cartan theory." Journal of Cosmology and Astroparticle Physics 2014, no. 06 (2014): 020. http://dx.doi.org/10.1088/1475-7516/2014/06/020.

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8

Sharif, Muhammad, and Muhammad Zeeshan Gul. "Stability Analysis of the Inhomogeneous Perturbed Einstein Universe in Energy–Momentum Squared Gravity." Universe 9, no. 3 (2023): 145. http://dx.doi.org/10.3390/universe9030145.

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The main objective of this article is to examine the stability of Einstein static universe using inhomogeneous perturbations in the context of energy–momentum squared gravity. For this purpose, we used FRW spacetime with perfect matter distribution and formulated static as well as perturbed field equations. We took a minimal model of this theory to investigate the stable regions of the Einstein universe for conserved and non-conserved energy–momentum tensors. We found that stable modes of the Einstein universe appeared in both conserved and non-conserved cases for all values of the equation of

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9

Sharif, M., and Sana Saleem. "Stability of anisotropic perturbed Einstein universe in f(R,T) theory." Modern Physics Letters A 35, no. 27 (2020): 2050222. http://dx.doi.org/10.1142/s0217732320502223.

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The aim of this paper is to investigate the stability of Einstein static cosmos using anisotropic homogeneous perturbations in the background of [Formula: see text] theory in which [Formula: see text] and [Formula: see text] express the Ricci scalar and trace of the stress–energy tensor, respectively. To accomplish this work, we consider perfect fluid distribution and adopt small anisotropic perturbations in the scale factors and matter contents. We develop static and perturbed field equations that are simplified by using equation of state parameter. For the specific models of [Formula: see te

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10

Heydarzade, Y., and F. Darabi. "Induced matter brane gravity and Einstein static universe." Journal of Cosmology and Astroparticle Physics 2015, no. 04 (2015): 028. http://dx.doi.org/10.1088/1475-7516/2015/04/028.

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11

Parisi, Luca, Marco Bruni, Roy Maartens, and Kevin Vandersloot. "The Einstein static universe in loop quantum cosmology." Classical and Quantum Gravity 24, no. 24 (2007): 6243–53. http://dx.doi.org/10.1088/0264-9381/24/24/007.

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12

Gergely, László Á., and Roy Maartens. "Brane-world generalizations of the Einstein static universe." Classical and Quantum Gravity 19, no. 2 (2002): 213–21. http://dx.doi.org/10.1088/0264-9381/19/2/303.

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13

Barrow, John D., George F. R. Ellis, Roy Maartens, and Christos G. Tsagas. "On the stability of the Einstein static universe." Classical and Quantum Gravity 20, no. 11 (2003): L155—L164. http://dx.doi.org/10.1088/0264-9381/20/11/102.

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14

ROY, BARNANA. "A NON-PERTURBATIVE APPROACH TO SYMMETRY BEHAVIOUR IN THE OPEN EINSTEIN UNIVERSE." International Journal of Modern Physics A 06, no. 09 (1991): 1525–32. http://dx.doi.org/10.1142/s0217751x91000800.

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15

Aygün, S., I. Tarhan, and H. Baysal. "On the Energy-Momentum Problem in Static Einstein Universe." Chinese Physics Letters 24, no. 2 (2007): 355–58. http://dx.doi.org/10.1088/0256-307x/24/2/015.

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16

Gruppuso, A., E. Roessl, and M. Shaposhnikov. "Einstein static universe as a brane in extra dimensions." Journal of High Energy Physics 2004, no. 08 (2004): 011. http://dx.doi.org/10.1088/1126-6708/2004/08/011.

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17

Atazadeh, K., and F. Darabi. "Einstein static Universe in non-minimal kinetic coupled gravity." Physics Letters B 744 (May 2015): 363–68. http://dx.doi.org/10.1016/j.physletb.2015.04.022.

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18

Chakrabarti, A. "Fermions and gauge fields in the Einstein static universe." Physics Letters B 212, no. 2 (1988): 145–46. http://dx.doi.org/10.1016/0370-2693(88)90514-x.

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19

Sharif, M., та Ayesha Ikram. "Stability analysis of Einstein universe in f(𝒢,T) gravity". International Journal of Modern Physics D 26, № 08 (2017): 1750084. http://dx.doi.org/10.1142/s0218271817500845.

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This paper explores the stability of the Einstein universe against linear homogeneous perturbations in the background of [Formula: see text] gravity. We construct static as well as perturbed field equations and investigate stability regions for the specific forms of generic function [Formula: see text] corresponding to conserved as well as nonconserved energy-momentum tensor. We use the equation-of-state parameter to parameterize the stability regions. The graphical analysis shows that the suitable choice of parameters lead to stable regions of the Einstein universe.

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20

GUENDELMAN, E. I. "NONSINGULAR ORIGIN OF THE UNIVERSE AND THE COSMOLOGICAL CONSTANT PROBLEM." International Journal of Modern Physics D 20, no. 14 (2011): 2767–71. http://dx.doi.org/10.1142/s0218271811020718.

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We consider a nonsingular origin for the universe starting from an Einstein static universe in the framework of a theory which uses two volume elements [Formula: see text] and Φd4x, where Φ is a metric independent density, also curvature, curvature square terms, first order formalism and for scale invariance a dilaton field ϕ are considered in the action. In the Einstein frame we also add a cosmological term that parametrizes the zero point fluctuations. The resulting effective potential for the dilaton contains two flat regions, for ϕ → ∞ relevant for the nonsingular origin of the universe an

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21

Darabi, F., and K. Atazadeh. "Einstein static universe, GUP, and natural IR and UV cut-offs." International Journal of Geometric Methods in Modern Physics 15, no. 05 (2018): 1850083. http://dx.doi.org/10.1142/s0219887818500834.

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We study the Einstein static universe (ESU) in the framework of Generalized Uncertainty Principle (GUP) constructed by the Snyder non-commutative space. It is shown that the deformation parameter can induce an effective energy density subject to GUP which obeys the holographic principle (HP) and plays the role of a cosmological constant. Using the holographic feature of this effective energy density, we introduce natural IR and UV cut-offs which depend on the GUP-based effective equation of state. Moreover, we propose a solution to the cosmological constant problem (CCP). This solution is base

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22

Ebert, D., K. G. Klimenko, A. V. Tyukov, and V. C. Zhukovsky. "Pion condensation of quark matter in a static Einstein universe." European Physical Journal C 58, no. 1 (2008): 57–68. http://dx.doi.org/10.1140/epjc/s10052-008-0667-6.

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23

Herdeiro, Carlos A. R., Raquel H. Ribeiro, and Marco Sampaio. "Scalar Casimir effect on a D -dimensional Einstein static universe." Classical and Quantum Gravity 25, no. 16 (2008): 165010. http://dx.doi.org/10.1088/0264-9381/25/16/165010.

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24

Zhang, Kaituo, Puxun Wu, and Hongwei Yu. "The stability of Einstein static universe in the DGP braneworld." Physics Letters B 690, no. 3 (2010): 229–32. http://dx.doi.org/10.1016/j.physletb.2010.05.040.

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25

Khokhlov, D. L. "The Einstein static model of the universe as a whole." Astrophysics and Space Science 333, no. 1 (2010): 209–12. http://dx.doi.org/10.1007/s10509-010-0565-x.

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26

Berman, M. S. "A static universe with magnetic field in Einstein-Cartan’s theory." Il Nuovo Cimento B Series 11 105, no. 12 (1990): 1373–75. http://dx.doi.org/10.1007/bf02742691.

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27

SHOJAI, ALI, FATIMAH SHOJAI, and NARESH DADHICH. "STATIC EINSTEIN'S UNIVERSE AS A QUANTUM SOLUTION OF CAUSAL QUANTUM GRAVITY." International Journal of Modern Physics A 20, no. 13 (2005): 2773–80. http://dx.doi.org/10.1142/s0217751x05022913.

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We shall in the framework of Bohmian quantum gravity show that it is possible to find a pure quantum state which leads to the static Einstein universe whose classical counterpart is flat space–time. We obtain the solution in the long-wavelength approximation. At the end an exact solution is found.

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28

Böhmer, Christian G., and Francisco S. N. Lobo. "Stability of the Einstein static universe in IR modified Hořava gravity." European Physical Journal C 70, no. 4 (2010): 1111–18. http://dx.doi.org/10.1140/epjc/s10052-010-1503-3.

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29

Heydarzade, Y., M. Khodadi, and F. Darabi. "Deformed Hořava–Lifshitz cosmology and stability of the Einstein static universe." Theoretical and Mathematical Physics 190, no. 1 (2017): 130–39. http://dx.doi.org/10.1134/s0040577917010111.

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30

Zhang, Kaituo, Puxun Wu, Hongwei Yu, and Ling-Wei Luo. "Stability of Einstein static state universe in the spatially flat branemodels." Physics Letters B 758 (July 2016): 37–41. http://dx.doi.org/10.1016/j.physletb.2016.04.049.

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31

Sharif, M., та Arfa Waseem. "On the stability of Einstein universe in f(R, T, Rμν Tμν) gravity". Modern Physics Letters A 33, № 36 (2018): 1850216. http://dx.doi.org/10.1142/s0217732318502164.

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This paper investigates the existence and stability of Einstein universe in the context of f(R, T, Q) gravity, where Q = R[Formula: see text] T[Formula: see text]. Considering linear homogeneous perturbations around scale factor and energy density, we formulate static as well as perturbed field equations. We parametrize the stability regions corresponding to conserved as well as non-conserved energy–momentum tensor using linear equation of state parameter for particular models of this gravity. The graphical analysis concludes that for a suitable choice of parameters, stable regions of the Eins

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32

HERDEIRO, CARLOS A. R., RAQUEL H. RIBEIRO, and MARCO SAMPAIO. "REPULSIVE GRAVITY AND THE CASIMIR EFFECT ON SPHERICAL UNIVERSES." International Journal of Modern Physics A 24, no. 08n09 (2009): 1821–24. http://dx.doi.org/10.1142/s0217751x09045406.

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We describe the Casimir effect of a free scalar field coupled to gravity on an n + 1-dimensional Einstein Static Universe (ESU), with arbitrary low energy effective operators (up to mass dimension n + 1). We discuss the variation of the effect from attractive to repulsive and some possible physical consequences.

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33

CHATTERJEE, S., Y. Z. ZHANG, and D. PANIGRAHI. "EINSTEIN–STRAUS PROBLEM IN HIGHER DIMENSIONS." International Journal of Modern Physics D 12, no. 03 (2003): 395–405. http://dx.doi.org/10.1142/s0218271803003116.

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Years ago Einstein and Straus (ES) showed that it is possible to match a static Schwarzschild region to an external expanding Friedmann universe. This model is extended in this work to a spacetime of arbitrary dimensions. Frequency shift of radiation coming from the boundary of the two spacetimes is calculated. Depending on the relative magnitude of gravitational and doppler effects our model gives both blue shift and red shift. The dynamical behaviour of the boundary is investigated and it is found that like the ES case our model is also unstable against small perturbation.

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34

Eshkobilov, Olimjon, Emilio Musso, and Lorenzo Nicolodi. "On the restricted conformal group of the (1+n)-Einstein static universe." Journal of Geometry and Physics 146 (December 2019): 103517. http://dx.doi.org/10.1016/j.geomphys.2019.103517.

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35

Fekecs, Barna, and Zoltán Keresztes. "Dark Energy and Cosmological Bounce Supported by an Unconventional Spinor Field." Universe 11, no. 2 (2025): 59. https://doi.org/10.3390/universe11020059.

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Alternative scenarios where the Big Bang singularity of the standard cosmological model is replaced by a bounce, or by an early almost static phase (known as emergent universe) have been frequently studied. We investigate the role of the spinor degrees of freedom in overcoming the initial singularity. We introduce a model which generalizes the Einstein–Cartan–Dirac theory, including local phase invariance of the spinor field supported by a gauge scalar field and certain couplings to the torsion. A natural gauge choice reduces the field equations to that of the Einstein–Dirac theory with a Dira

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36

Hamil, B., M. Merad, and T. Birkandan. "Particle creation in the context of the emergent universe." Revista Mexicana de Física 67, no. 2 Mar-Apr (2021): 219–25. http://dx.doi.org/10.31349/revmexfis.67.219.

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We study the mechanism of particle creation in the context of the emergent universe (EU) scenario which is privileged by certain important characteristics such as the absence of time-like singularity. EU asymptotically coincides with an Einstein static model in the infinite past and it approaches to a de Sitter expansion phase at late times. By introducing the conformal time, we obtain the solution of the Klein-Gordon equation and by applying the "in" and "out" states method, the total number of produced particles and the total energy associated with them are determined.

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37

Singh, Kangujam Priyokumar, and Asem Jotin Meitei. "Late time acceleration in Bianchi type-V dark energy cosmological models with linear deceleration parameter." Physica Scripta 99, no. 7 (2024): 075046. http://dx.doi.org/10.1088/1402-4896/ad5889.

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Abstract We present a Bianchi type-V cosmological model with deceleration parameter as a simple linear function of the Hubble parameter interacting with a perfect fluid in the general theory of relativity. For Bianchi type-V space-time, the available solutions of Einstein field equations have been procure under the assumption of linear deceleration parameter, q = A + BH, where H is the Hubble parameter. Also,during the evolution of the Bianchi-V universe, dark energy(DE) with a variable EoS parameters has been studied in detail and w slowly varies around w = –0.33 for a 10 GYr. lapse, which in

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38

Riazi, N., H. Moradpour, and A. Sheykhi. "Conformally Schwarzschild black holes in an accelerating universe." International Journal of Modern Physics D 23, no. 05 (2014): 1450048. http://dx.doi.org/10.1142/s0218271814500485.

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We investigate the physical properties of conformally Schwarzschild black holes (BHs) in a background of accelerating universe. We discuss the effect of the cosmic expansion on the principal quantities of the BH such as mass, temperature, entropy and horizon radius. In particular, we investigate the quasi-static thermodynamics of the BH by considering the fact that the cosmic expansion is very slow on local time scales. We show that, by imposing a condition on Ricci scalar, one can describe time-dependent, spherically symmetric solutions of Einstein gravity in an accelerating universe backgrou

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39

GUENDELMAN, E. I. "NONSINGULAR ORIGIN OF THE UNIVERSE AND ITS PRESENT VACUUM ENERGY DENSITY." International Journal of Modern Physics A 26, no. 17 (2011): 2951–72. http://dx.doi.org/10.1142/s0217751x11053614.

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We consider a nonsingular origin for the universe starting from an Einstein static universe, the so-called "emergent universe" scenario, in the framework of a theory which uses two volume elements [Formula: see text] and Φd4x, where Φ is a metric independent density, used as an additional measure of integration. Also curvature, curvature square terms and for scale invariance a dilaton field ϕ are considered in the action. The first-order formalism is applied. The integration of the equations of motion associated with the new measure gives rise to the spontaneous symmetry breaking of scale inva

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40

Cavaglià, Marco, and Vittorio de Alfaro. "Quantization of an Integrable Minisuperspace Model in Dilaton-Einstein Gravity." International Journal of Modern Physics D 06, no. 01 (1997): 39–47. http://dx.doi.org/10.1142/s0218271897000030.

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We quantize the minisuperspace model of Einstein gravity plus dilaton that describeseither a static spherically symmetric configuration or a Kantowski–Sachs like universe. We develop the canonical formalism and identify canonical quantities that generate rigid symmetries of the Hamiltonian. Quantization is performed both by the Dirac and the reduced methods. Since the system is classically integrable we show that both approaches lead to the same positive definite Hilbert space.

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41

KAN, NAHOMI, KOICHIRO KOBAYASHI, and KIYOSHI SHIRAISHI. "GRAPH-THEORY INDUCED GRAVITY AND STRONGLY-DEGENERATE FERMIONS IN A SELF-CONSISTENT EINSTEIN UNIVERSE." International Journal of Modern Physics A 27, no. 23 (2012): 1250131. http://dx.doi.org/10.1142/s0217751x1250131x.

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We study UV-finite theory of induced gravity. We use scalar fields, Dirac fields and vector fields as matter fields whose one-loop effects induce the gravitational action. To obtain the mass spectrum that satisfies the UV-finiteness condition, we use a graph-based construction of mass matrices. The existence of a self-consistent static solution for an Einstein universe is shown in the presence of degenerate fermions.

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42

Mousavi, M., and F. Darabi. "On the stability of Einstein static universe at background level in massive bigravity." Nuclear Physics B 919 (June 2017): 523–40. http://dx.doi.org/10.1016/j.nuclphysb.2017.04.002.

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43

Miao, Haitao, Puxun Wu, and Hongwei Yu. "Stability of the Einstein static Universe in the scalar–tensor theory of gravity." Classical and Quantum Gravity 33, no. 21 (2016): 215011. http://dx.doi.org/10.1088/0264-9381/33/21/215011.

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44

Tung, Michael M. "Metamaterial Acoustics on the (2 + 1)D Einstein Cylinder." Mathematics 9, no. 17 (2021): 2079. http://dx.doi.org/10.3390/math9172079.

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The Einstein cylinder is the first cosmological model for our universe in modern history. Its geometry not only describes a static universe—a universe being invariant under time reversal—but it is also the prototype for a maximally symmetric spacetime with constant positive curvature. As such, it is still of crucial importance in numerous areas of physics and engineering, offering a fruitful playground for simulations and new theories. Here, we focus on the implementation and simulation of acoustic wave propagation on the Einstein cylinder. Engineering such an extraordinary device is the terri

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45

Rebecca, Louise, C. Sivaram, and Kenath Arun. "Dark Energy and Cosmological Constant." Mapana - Journal of Sciences 17, no. 1 (2018): 25–32. http://dx.doi.org/10.12723/mjs.44.3.

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One of the unresolved problems in cosmology is that the measured mass density of the universe has revealed a value that was about 30% of the critical density. Since the universe is very nearly spatially flat, as is indicated by measurements of the cosmic microwave background, about 70% of the energy density of the universe was left unaccounted for. Another observation seems to be connected to this mystery. Generally one would expect the rate of expansion to slow down once the universe started expanding. The measurements of Type Ia supernovae have revealed that the expansion of the universe is

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46

GUENDELMAN, EDUARDO I., and PEDRO LABRAÑA. "CONNECTING THE NONSINGULAR ORIGIN OF THE UNIVERSE, THE VACUUM STRUCTURE AND THE COSMOLOGICAL CONSTANT PROBLEM." International Journal of Modern Physics D 22, no. 09 (2013): 1330018. http://dx.doi.org/10.1142/s0218271813300188.

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We consider a nonsingular origin for the universe starting from an Einstein static universe, the so-called "emergent universe" scenario, in the framework of a theory which uses two volume elements [Formula: see text] and Φd4x, where Φ is a metric independent density, used as an additional measure of integration. Also curvature, curvature square terms and for scale invariance a dilaton field ϕ are considered in the action. The first-order formalism is applied. The integration of the equations of motion associated with the new measure gives rise to the spontaneous symmetry breaking (SSB) of scal

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47

NUSSBAUMER, HARRY. "THE DISCOVERY OF THE EXPANDING UNIVERSE AND 80 YEARS OF BIG BANG." International Journal of Modern Physics D 20, supp01 (2011): 87–103. http://dx.doi.org/10.1142/s0218271811019402.

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Modern cosmology began in 1917 when Einstein published his model of a static Universe built on general relativity. A few months later de Sitter came forward with a competing, but also static model which contained no matter but had the intriguing quality that the spectrum of a test particle appeared redshifted to a distant observer. It was thought that de Sitter's model might explain the redshifted spectra observed by Slipher in spiral nebulae. However, in 1927 Lemaître showed that de Sitter's model violated the principle of homogeneity. He then formulated a dynamical cosmological model and com

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48

Nian, Jun, and Yachao Qian. "Exact multi-instanton solutions to self-dual Yang–Mills equation on curved spaces." International Journal of Modern Physics A 36, no. 17 (2021): 2150132. http://dx.doi.org/10.1142/s0217751x21501323.

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We find exact multi-instanton solutions to the self-dual Yang–Mills equation on a large class of curved spaces with [Formula: see text] isometry, generalizing the results previously found on [Formula: see text]. The solutions are featured with explicit multi-centered expressions and topological properties. As examples, we demonstrate the approach on several different curved spaces, including the Einstein static universe and [Formula: see text], and show that the exact multi-instanton solutions exist on these curved backgrounds.

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49

Böhmer, C. G. "The Einstein static universe with torsion and the sign problem of the cosmological constant." Classical and Quantum Gravity 21, no. 4 (2004): 1119–24. http://dx.doi.org/10.1088/0264-9381/21/4/025.

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50

Garcia de Andrade, L. C. "Generation of Primordial Magnetic Fields from QED and Higgs-like Domain Walls in Einstein–Cartan Gravity." Universe 8, no. 12 (2022): 658. http://dx.doi.org/10.3390/universe8120658.

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Spacetime torsion is known to be highly suppressed at the end of inflation, which is called preheating. This result was recently shown in (EPJ C (2022)) in the frame of Einstein–Cartan–Brans–Dicke inflation. In this paper, it is shown that a torsionful magnetogenesis in QED effective Lagrangean drives a torsion damping in order to be subsequently amplified by the dynamo effect after the generation of these magnetic fields seeds. This damping on amplification would depend upon the so-called torsion chirality. Here, a cosmic factor gkK is present where K is the contortion vector and k is the wav

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