10 papers
A Friendly Phantom: Late-time AdS-to-dS transition and cosmological tensions
Ãzgür Akarsu, Leandros Perivolaropoulos, A. Emrah Yükselci +1
We present Ph-CDM, a phantom-scalar realization within General Relativity of the sign-switching cosmological-constant idea, CDM, in which a phantom scalar e…
Updated Constraints on Omnipotent Dark Energy: A Comprehensive Analysis with CMB and BAO Data
Enrico Specogna, Shahnawaz A. Adil, Emre Ozulker +4
In this work, we present updated observational constraints on the parameter space of the DMS20 dark energy model, a member of the omnipotent dark energy (ODE) class. Our analysis c…
Negative neutrino mass or negative dark energy?
Cihad Kıbrıs, Willem Elbers, Ãzgür Akarsu +1
Recent cosmological analyses based on DESI and CMB data have revealed a tension between the inferred sum of neutrino masses and the minimum value allowed by neutrino oscillation ex…
Do equation of state parametrizations of dark energy faithfully capture the dynamics of the late universe?
Ãzgür Akarsu, Maria Caruana, Konstantinos F. Dialektopoulos +3
We investigate how strongly late-time inferences about DE dynamics depend on the functional prior used to represent the expansion history. Using identical late-time combinations of…
Nonlinear Matter Power Spectrum from relativistic -body Simulations: CDM versus CDM
Ãzgür Akarsu, Eleonora Di Valentino, JiÅà VyskoÄil +3
We present relativistic -body simulations of a CDM - sign-switching cosmological constant (CC) - scenario under general relativity and compare its nonlinear matter p…
Revisiting CPL with sign-switching density: To cross or not to cross the NECB
Mine Gökçen, Ãzgür Akarsu, Eleonora Di Valentino
Recent DESI DR2 BAO measurements, when combined with CMB and SNeIa data, exhibit a - preference for dynamical dark energy (DE) described by the CPL-parametrized equat…