827 citations · 16k across the 208 of their papers we have counts for
10 papers · 1 filter
Constraining the magnetic field on white dwarf surfaces; Zeeman effects and fine structure constant variation
J. Hu, J. K. Webb, T. R. Ayres +12
White dwarf atmospheres are subjected to gravitational potentials around times larger than occur on Earth. They provide a unique environment in which to search for any possi…
Friedmann-like universes with torsion
D. Kranas, C. G. Tsagas, J. D. Barrow +1
We consider spatially homogeneous and isotropic cosmologies with non-zero torsion. Given the high symmetry of these universes, we adopt a specific form for the torsion tensor that…
Szekeres Universes with Homogeneous Scalar Fields
John D. Barrow, Andronikos Paliathanasis
We consider the existence of an "inflaton" described by an homogeneous scalar field in the Szekeres cosmological metric. The gravitational field equations are reduced to two famili…
Do we live in an eigenstate of the "fundamental constants" operators?
John D. Barrow, Joao Magueijo
We propose that the constants of Nature we observe (which appear as parameters in the classical action) are quantum observables in a kinematical Hilbert space. When all of these ob…
Cosmological singularities and analytical solutions in varying vacuum cosmologies
S. Basilakos, A. Paliathanasis, J. D. Barrow +1
We investigate the dynamical features of a large family of running vacuum cosmologies for which evolves as a polynomial in the Hubble parameter. Specifically, using the critica…
Relativistic magnetised perturbations: magnetic pressure vs magnetic tension
Dimitra Tseneklidou, Christos G. Tsagas, John D. Barrow
We study the linear evolution of magnetised cosmological perturbations in the post-recombination epoch. Using full general relativity and adopting the ideal magnetohydrodynamic app…
Constraining Density Fluctuations with Big Bang Nucleosynthesis in the Era of Precision Cosmology
John D. Barrow, Robert J. Scherrer
We reexamine big bang nucleosynthesis with large-scale baryon density inhomogeneities when the length scale of the density fluctuations exceeds the neutron diffusion length ($\sim…
Inhomogeneous Initial Data and Small-Field Inflation
M. C. David Marsh, John D. Barrow, Chandrima Ganguly
We consider the robustness of small-field inflation in the presence of scalar field inhomogeneities. Previous numerical work has shown that if the scalar potential is flat only ove…
Constraint on energy-momentum squared gravity from neutron stars and its cosmological implications
Ozgur Akarsu, John D. Barrow, Sercan Çıkıntoğlu +2
Deviations from the predictions of general relativity due to energy-momentum squared gravity (EMSG) are expected to become pronounced in the high density cores of neutron stars. We…
New integrable models and analytical solutions in ~cosmology with an ideal gas
G. Papagiannopoulos, Spyros Basilakos, John D. Barrow +1
In the context of -gravity with a spatially flat FLRW metric containing an ideal fluid, we use the method of invariant transformations to specify families of mod…