401 citations · 2.9k across the 98 of their papers we have counts for
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Higher dimensional VSI spacetimes
A. Coley, A. Fuster, S. Hervik +1
We present the explicit metric forms for higher dimensional vanishing scalar invariant (VSI) Lorentzian spacetimes. We note that all of the VSI spacetimes belong to the higher dime…
On the evolution of universes in quadratic theories of gravity
John D. Barrow, Sigbjorn Hervik
We use a dynamical systems approach to investigate Bianchi type I and II universes in quadratic theories of gravity. Due to the complicated nature of the equations of motion we foc…
Kinematic and Weyl singularities
W. C. Lim, A. A. Coley, S. Hervik
We study the properties of a future singularity encountered by a perfect fluid observer in tilting spatially homogeneous Bianchi cosmologies. We derive the boost formulae for the W…
Fluid observers and tilting cosmology
A. A. Coley, S. Hervik, W. C. Lim
We study perfect fluid cosmological models with a constant equation of state parameter in which there are two naturally defined time-like congruences, a geometrically defined g…
Cosmology: a bird's eye view
Alan A. Coley, Sigbjorn Hervik, Woei Chet Lim
In this essay we discuss the difference in views of the Universe as seen by two different observers. While one of the observers follows a geodesic congruence defined by the geometr…