17 citations · 27 across the 3 of their papers we have counts for
3 papers · 1 filter
Gravitating sources with zero energy density in cosmology
Özgür Akarsu, Cihad Kıbrıs, Burcu Öztürk +1
A cosmological source can have identically zero comoving energy density and still gravitate through its pressure. This differs from an energy density passing through zero at an iso…
Defocusing dark energy: Raychaudhuri diagnostics beyond and the phantom divide
Özgür 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}…
Unexplored regions in teleparallel gravity: Sign-changing dark energy density
Ozgur Akarsu, Bilal Bulduk, Antonio De Felice +2
While gravity has shown considerable potential in addressing cosmological tensions, we explore previously overlooked solution spaces that hold further promise. We examine th…