From the 1 of 11 linked papers with an AI index.
11 papers
Defocusing dark energy: Raychaudhuri diagnostics beyond and the phantom divide
Ãzgür Akarsu, Antonio De Felice, N. Merve Uzun
In general relativity, cosmic acceleration is timelike defocusing of the comoving congruence and requires a negative total active gravitational mass density, $\mathcal{M}_{\rm tot}…
Background-level reconstruction of scalar-field potentials from dark-energy histories and comparison with analytic potential families
Shahnawaz A. Adil, Miguel A. Zapata, Ãzgür Akarsu +1
The paper introduces a framework to reconstruct scalar‑field potentials that reproduce a given dark‑energy density history in a flat FLRW universe, applies it to several benchmark…
Probing dynamical dark energy with late-time data: Evidence, tensions, and the limits of the CDM framework
Tengpeng Xu, Suresh Kumar, Yun Chen +4
We test the dynamical dark-energy CDM (CPL) framework against CDM using CMB anisotropies and lensing together with DESI DR2, SDSS-IV, transverse/angular BAO (BAOtr), and…
CDM cosmology from a type-II minimally modified gravity
Ãzgür Akarsu, Antonio De Felice, Eleonora Di Valentino +5
We integrate CDM, a promising scenario for alleviating cosmological tensions, into VCDM, a type-II minimally modified gravity. This promotes the scenario to a fully pre…
Quadratic energy-momentum squared gravity: constraints from big bang nucleosynthesis
Ozgur Akarsu, Mariam Bouhmadi-López, Nihan Katirci +1
In this work, we extend the standard cosmological model within the quadratic energy-momentum squared gravity (qEMSG) framework, introducing a nonminimal interaction between the usu…
k-inflation: Non-separable case meets ACT measurements
Tahere Fallahi Serish, Seyed Ali Hosseini Mansoori, Fereshteh Felegary +2
We investigate a non-separable subset of -essence in which the kinetic and potential sectors interact through an coupling, implemented via a potential-dependent pref…