346 citations · 3.7k across the 115 of their papers we have counts for
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Global dynamics of two models for Quintom Friedman-Lemaître-Robertson-Walker Universes
Genly Leon, Alan Coley, Andronikos Paliathanasis +2
We comprehensively analyze the dynamics for the gravitational field equations for the Chiral-Quintom theory in a Friedman-Lemaître-Robertson-Walker cosmology with an additional mat…
Spatially Homogeneous Teleparallel Gravity: Bianchi I
A. A. Coley, R. J. van den Hoogen
Using a recently developed algorithm that chooses preferred coordinates and a preferred co-frame, we will determine the completely general Bianchi type I teleparallel geometry. In…
The equilibrium condition in gravitational collapse and its application to a cosmological scenario
Dipanjan Dey, N. T. Layden, A. A. Coley +1
We discuss the equilibrium conditions of the gravitational collapse of a spherically symmetric matter cloud. We analyze the spinor structure of a general collapsing space-time and…
A frame based approach to computing symmetries with non-trivial isotropy groups
D. D. McNutt, A. A. Coley, R. J. van den Hoogen
A frame approach to determining the most general solution admitting a desired symmetry group has been examined previously in Riemannian and teleparallel geometries with some succes…
Teleparallel Geometry with a Single Affine Symmetry
Alan Coley, Robert van den Hoogen
In teleparallel geometries, symmetries are represented by affine frame symmetries which constrain both the (co)frame basis and the spin-connection (which are the primary geometric…
The dynamics of scalar-field Quintom cosmological models
Jonathan Tot, Balkar Yildirim, Alan Coley +1
We shall present a complete (compactified) dynamical systems analysis of the Quintom model comprised of an interacting quintessence scalar field and a phantom. We find a range for…
Geometric horizons in binary black hole mergers
Alan Coley, Jeremy M Peters, Erik Schnetter
We numerically study the algebraic properties of the Weyl tensor through the merger of two non-spinning black holes (BHs). We are particularly interested in the conjecture that for…
Geometric Horizons: A Frame Approach
A. A. Coley, D. D. McNutt
In the numerical investigation of the physical merger of two black holes, it is crucial to locate a black hole locally. This is usually done utilizing an apparent horizon. An alter…
Teleparallel geometries not characterized by their scalar polynomial torsion invariants
D. D. McNutt, A. A. Coley, R. J. van den Hoogen
A teleparallel geometry is an n-dimensional manifold equipped with a frame basis and an independent spin connection. For such a geometry, the curvature tensor vanishes and the tors…
Comment on "Szekeres universes with homogeneous scalar fields"
Ismael Delgado Gaspar, Roberto A. Sussman, David D. McNutt +1
Two recently published papers (J.D. Barrow and A. Paliathanasis, Eur. Phys. J. C. (2018, 2019)) claim to have found exact solutions of Einstein's field equations belonging to the c…
An invariant characterization of the quasi-spherical Szekeres dust models
A. A. Coley, N. Layden, D. D. McNutt
The quasi-spherical Szekeres dust solutions are a generalization of the spherically symmetric Lemaitre-Tolman-Bondi dust models where the spherical shells of constant mass are non-…
Curvature Invariants and the Geometric Horizon Conjecture in a Binary Black Hole Merger
Jeremy M. Peters, Alan Coley, Erik Schnetter
We study curvature invariants in a binary black hole merger. It has been conjectured that one could define a quasi-local and foliation independent black hole horizon by finding the…
Observer-based invariants for cosmological models
Lode Wylleman, Alan Coley, David McNutt +1
We consider the equivalence problem for cosmological models in four-dimensional gravity theories. A cosmological model is considered as a triple consisting o…
Symmetry and Equivalence in Teleparallel Gravity
A. A. Coley, R. J. van den Hoogen, D. D. McNutt
In theories such as teleparallel gravity and its extensions, the frame basis replaces the metric tensor as the primary object of study. A choice of coordinate system, frame basis a…
Static Spherically Symmetric Einstein-aether models II: Integrability and the Modified Tolman-Oppenheimer-Volkoff approach
Genly Leon, A. Coley, Andronikos Paliathanasis
We investigate the existence of analytic solutions for the field equations in the Einstein-æther theory for a static spherically symmetric spacetime and provide a detailed dynamica…
Spatial Curvature in Cosmology Revisited
A. A. Coley
It is necessary to make assumptions in order to derive models to be used for cosmological predictions and comparison with observational data. In particular, in standard cosmology t…
Static Spherically Symmetric Einstein-aether models I: Perfect fluids with a linear equation of state and scalar fields with an exponential self-interacting potential
Alan Coley, Genly Leon
We investigate the field equations in the Einstein-aether theory for static spherically symmetric spacetimes and a perfect fluid source and subsequently with the addition of a scal…
Geometric Horizons in the Kastor-Traschen Multi Black Hole Solutions
D. D. McNutt, A. A. Coley
We investigate the existence of invariantly defined quasi-local hypersurfaces in the Kastor-Traschen solution containing charge-equal-to-mass black holes. These hypersurfaces a…
Teleparallel Theories of Gravity: Illuminating a Fully Invariant Approach
M. Krssak, R. J. van den Hoogen, J. G. Pereira +2
Teleparallel gravity and its popular generalization gravity can be formulated as fully invariant (under both coordinate transformations and local Lorentz transformations) th…
Kantowski-Sachs Einstein-Aether Scalar Field Cosmological Models
R. J. van den Hoogen, A. A. Coley, B. Alhulaimi +3
A class of positive curvature spatially homogeneous but anisotropic cosmological models within an Einstein-aether gravitational framework are investigated. The matter source is ass…
Mathematical General Relativity
Alan A. Coley
We present a number of open problems within general relativity. After a brief introduction to some technical mathematical issues and the famous singularity theorems, we discuss the…
Geometric Horizons
Alan A. Coley, David D. McNutt, Andrey A. Shoom
We discuss black hole spacetimes with a geometrically defined quasi-local horizon on which the curvature tensor is algebraically special relative to the alignment classification. B…
Identification of black hole horizons using scalar curvature invariants
Alan Coley, David McNutt
We introduce the concept of a geometric horizon, which is a surface distinguished by the vanishing of certain curvature invariants which characterize its special algebraic characte…
Spatially Homogeneous Einstein-Aether Cosmological Models: Scalar Fields with a Generalized Harmonic Potential
B. Alhulaimi, R. J. van den Hoogen, A. A. Coley
Inflationary spatially homogeneous cosmological models within an Einstein-Aether gravitational framework are investigated. The matter source is assumed to be a scalar field which i…