Zobrazeno 1 - 10
of 3 807
pro vyhledávání: '"Saridakis"'
$f(Q)$ and $f(T)$ gravity are based on fundamentally different geometric frameworks, yet they exhibit many similar properties. In this article, we identify two types of background-dependent and classical correspondences between these two theories of
Externí odkaz:
http://arxiv.org/abs/2412.01104
We perform a detailed investigation of interacting phantom cosmology, by applying the powerful method of dynamical system analysis. We consider two well-studied interaction forms, namely one global and one local one, while the novel ingredient of our
Externí odkaz:
http://arxiv.org/abs/2411.18300
We use Weyl connection and Weyl geometry in order to construct novel modified gravitational theories. In the simplest case where one uses only the Weyl-connection Ricci scalar as a Lagrangian, the theory recovers general relativity. However, by upgra
Externí odkaz:
http://arxiv.org/abs/2411.14380
Autor:
Tzerefos, Charalampos, Papanikolaou, Theodoros, Basilakos, Spyros, Saridakis, Emmanuel N., Mavromatos, Nick E.
Within the context of a Chern-Simons running-vacuum-model (RVM) cosmology, one expects an early-matter dominated (eMD) reheating period after RVM inflation driven by the axion field. Treating thus in this work Chern-Simons RVM cosmology as an effecti
Externí odkaz:
http://arxiv.org/abs/2411.14223
Autor:
Santos, Fabiano F., Pourhassan, Behnam, Saridakis, Emmanuel N., Sokoliuk, Oleksii, Baransky, Alexander, Kahya, Emre Onur
We investigate entanglement islands and the Page curve in the framework of Horndeski gravity on a Karch-Randall braneworld background. In particular, treating the holographic boundary conformal field theory analytically we find that the Horndeski par
Externí odkaz:
http://arxiv.org/abs/2410.18781
We investigate the strong coupling problem in modified teleparallel gravity theories using the effective field theory (EFT) approach, demonstrating that it is possible to shift the emergence of new degrees of freedom (DoFs) to lower orders in perturb
Externí odkaz:
http://arxiv.org/abs/2410.03422
Autor:
He, Xin-Chen, Cai, Yi-Fu, Ma, Xiao-Han, Papanikolaou, Theodoros, Saridakis, Emmanuel N., Sasaki, Misao
Ultra-light primordial black holes (PBHs) with masses $M_{\rm PBH}<5\times 10^8\mathrm{g}$ can dominate transiently the energy budget of the Universe and reheat the Universe through their evaporation taking place before Big Bang Nucleosynthesis. The
Externí odkaz:
http://arxiv.org/abs/2409.11333
Autor:
Basilakos, Spyros, Nanopoulos, Dimitri V., Papanikolaou, Theodoros, Saridakis, Emmanuel N., Tzerefos, Charalampos
In light of NANOGrav data we provide for the first time possible observational signatures of Superstring theory. Firstly, we work with inflection-point inflationary potentials naturally realised within Wess-Zumino type no-scale Supergravity, which gi
Externí odkaz:
http://arxiv.org/abs/2409.02936
We investigate the dynamics of fermion localization within the framework of $f(T, B)$ gravity featuring non-minimal couplings. Starting from the Dirac action for a spin-$1/2$ fermion in a five-dimensional spacetime governed by torsional $f(T, B)$ gra
Externí odkaz:
http://arxiv.org/abs/2407.15190
Publikováno v:
Astrophys.J. 974 (2024) 1, 7
In this article we confront a class of $f(Q)$ gravity models with observational data of galaxy-galaxy lensing. Specifically, we consider the $f(Q)$ gravity models containing a small quadratic correction when compared with General Relativity (GR), and
Externí odkaz:
http://arxiv.org/abs/2406.00242