Search Results - "Oikonomou, V. K."

Singular bouncing cosmology from Gauss-Bonnet modified gravity by Oikonomou, V. K.

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Singular inflationary universe from F ( R ) gravity by Odintsov, S. D., Oikonomou, V. K.

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Viable inflationary models in a ghost-free Gauss–Bonnet theory of gravity by Nojiri, Shin’ichi, Odintsov, S. D., Oikonomou, V. K., Chatzarakis, N., Paul, Tanmoy

“…In this work we investigate the inflationary phenomenological implications of a recently developed ghost-free Gauss–Bonnet theory of gravity. The resulting…”
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Anisotropic compact stars in higher-order curvature theory by Nashed, G. G. L., Odintsov, S. D., Oikonomou, V. K.

“…In this paper we shall consider spherically symmetric spacetime solutions describing the interior of stellar compact objects, in the context of higher-order…”
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Superbounce and loop quantum cosmology ekpyrosis from modified gravity by Oikonomou, V. K.

“…As is known, in modified cosmological theories of gravity many of the cosmologies which could not be generated by standard Einstein gravity, can be…”
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Reissner–Nordström Anti-de Sitter Black Holes in Mimetic F(R) Gravity by Oikonomou, V. K.

“…In this paper, we study under which conditions the Reissner–Nordström anti-de Sitter black hole can be a solution of the vacuum mimeticF(R)gravity with…”
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Bouncing loop quantum cosmology in Gauss-Bonnet gravity by Haro, J., Makarenko, A. N., Myagky, A. N., Odintsov, S. D., Oikonomou, V. K.

“…We develop an effective Gauss-Bonnet extension of loop quantum cosmology, by introducing holonomy corrections in modified F(G) theories of gravity. Within the…”
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Probing Our Universe’s Past Using Earth’s Geological and Climatological History and Shadows of Galactic Black Holes by Oikonomou, V. K., Tsyba, Pyotr, Razina, Olga

“…In this short review, we discuss how Earth’s climatological and geological history and also how the shadows of galactic black holes might reveal our Universe’s…”
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Effects of finite-time singularities on gravitational waves by Kleidis, K., Oikonomou, V. K.

“…We analyze the impact of finite-time singularities on gravitational waves, in the context of F ( R ) gravity. We investigate which singularities are allowed to…”
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Singular accelerated evolution in massive F ( R ) bigravity by Nojiri, S., Odintsov, S. D., Oikonomou, V. K.

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R2 gravity effects on the kinetic axion phase space by Oikonomou, V. K.

“…In this work we consider the effect of an R2 term on the kinetic misalignment axion theory. By using the slow-roll assumptions during inflation and the field…”
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Did the Universe experience a pressure non-crushing type cosmological singularity in the recent past? by Odintsov, S. D., Oikonomou, V. K.

“…In the recent literature it has been shown that the H 0 tension may be eliminated if an abrupt physics transition changed the Cepheid parameters in the near…”
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Rectifying an inconsistency in F(R) gravity inflation by Oikonomou, V. K.

“…In this letter we shall provide a formal derivation of the inflationary slow-roll indices for F(R) gravity from the power spectrum without the condition ,…”
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Aspects of axion F(R) gravity by Odintsov, S. D., Oikonomou, V. K.

“…We provide a compact review on recent developments on axion F(R) gravity. The axion field is a string-theory-originated theoretical particle that is a perfect…”
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Red or blue tensor spectrum from GW170817-compatible Einstein-Gauss-Bonnet theory: A detailed analysis by Oikonomou, V. K., Tsyba, Pyotr, Razina, Olga

“…In this work we shall prove that the tensor spectral index of the primordial tensor perturbations for GW170817-compatible Einstein-Gauss-Bonnet theories, takes…”
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Finite-time singularities in swampland-related dark-energy models by Odintsov, S. D., Oikonomou, V. K.

“…In this work we shall investigate the singularity structure of the phase space corresponding to an exponential quintessence dark-energy model recently related…”
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A nearly massless graviton in Einstein-Gauss-Bonnet inflation with linear coupling implies constant-roll for the scalar field by Oikonomou, V. K., Fronimos, F. P.

“…The striking GW170817 event indicated that the graviton is nearly massless, since the gamma rays emitted from the two neutron stars merging arrived almost…”
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Maximum baryon masses for static neutron stars in f(R) gravity by Astashenok, A. V., Capozziello, S., Odintsov, S. D., Oikonomou, V. K.

“…We investigate the upper mass limit predictions of the baryonic mass for static neutron stars in the context of f ( R ) gravity. We use the most popular f ( R…”
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Dissimilar donuts in the sky? Effects of a pressure singularity on the circular photon orbits and shadow of a cosmological black hole by Odintsov, S. D., Oikonomou, V. K.

“…The black hole observations obtained so far indicate one thing: similar “donuts” exist in the sky. But what if some of the observed black hole shadows that…”
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Gauss-Bonnet cosmology unifying late and early-time acceleration eras with intermediate eras by Oikonomou, V. K.

“…In this paper we demonstrate that with vacuum F ( G ) gravity it is possible to describe the unification of late and early-time acceleration eras with the…”
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