827 citations · 16k across the 208 of their papers we have counts for
10 papers · 1 filter
Graduated dark energy: Observational hints of a spontaneous sign switch in the cosmological constant
Ozgur Akarsu, John D. Barrow, Luis A. Escamilla +1
We study the cosmological constant () in the standard CDM model by introducing the \textit{graduated dark energy} (gDE) characterised by a minimal dynamical deviation from th…
Sudden Singularities in Brans-Dicke Cosmology and its Generalisations
John D. Barrow
We show that cosmological sudden singularities that respect the energy conditions can occur at finite times in Brans-Dicke and more general scalar-tensor theories of gravity. We co…
Friedmann-like universes with weak torsion: a dynamical system approach
J. D. Barrow, C. G. Tsagas, G. Fanaras
We consider Friedmann-like universes with torsion and take a step towards studying their stability. In so doing, we apply dynamical-system techniques to an autonomous system of dif…
Non-linear interactions in cosmologies with energy exchange
John D. Barrow, Georgia Kittou
We investigate the case of two interacting fluids in homogeneous and isotropic cosmologies with a non-linear interaction term. The interaction term avoids the unrealistic form gene…
Inflation Without a Trace of Lambda
John D. Barrow, Spiros Cotsakis
We generalise Einstein's formulation of the traceless Einstein equations to gravity theories. In the case of the vacuum traceless Einstein equations, we show that a non-cons…
Dynamics of Einstein-Aether Scalar field Cosmology
Andronikos Paliathanasis, G. Papagiannopoulos, Spyros Basilakos +1
We study the cosmological evolution of the field equations in the context of Einstein-Aether cosmology by including a scalar field in a spatially flat Friedmann--Lema\^ıtre--Robert…
A far-UV survey of three hot, metal-polluted white dwarf stars: WD0455-282, WD0621-376, and WD2211-495
S. P. Preval, M. A. Barstow, M. Bainbridge +7
Using newly obtained high-resolution data () from the \textit{Hubble Space Telescope}, and archival UV data from the \textit{Far Ultraviolet Spectroscopic E…
Screening in a new modified gravity model
Ozgur Akarsu, John D. Barrow, Charles V. R. Board +2
We study a new model of Energy-Momentum Squared Gravity (EMSG), called Energy-Momentum Log Gravity (EMLG), constructed by the addition of the term $f(T_{μν}T^{μν})=α\ln(λ\,T_{μν}T^…
Two-fluid solutions of particle-creation cosmologies
Supriya Pan, John D. Barrow, Andronikos Paliathanasis
Cosmological evolution driven incorporating continuous particle creation by the time-varying gravitational field is investigated. We consider a spatially flat, homogeneous and isot…
Cyclic Szekeres Universes
John D. Barrow, Andronikos Paliathanasis
We consider the Szekeres universe with an inhomogeneous dust fluid and a homogeneous and isotropic ghost matter source with equation of state where…