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Now showing items 1-10 of 30

#### Observational Cosmology in Macroscopic Gravity

We discuss the construction of cosmological models within the framework of Macroscopic Gravity (MG), which is a theory that models the effects of averaging the geometry of space-time on large scales. We find new exact ...

#### FRW cosmology in Milgrom's bimetric theory of gravity

We consider spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) solutions of Milgrom's recently proposed class of bimetric theories of gravity. These theories have two different regimes, corresponding to ...

#### Observational Constraints on the Completeness of Space near Astrophysical Objects

We consider the observational effects of a deficit angle, w, in the topology of the solar system and in the 'double pulsar' system PSR J0737-3039A/B. Using observations of the perihelion precession of Mercury, and the ...

#### Errors in Estimating Omega_Lambda due to the Fluid Approximation

The matter content of the Universe is strongly inhomogeneous on small scales. Motivated by this fact, we consider a model of the Universe that has regularly spaced discrete masses, rather than a continuous fluid. The optical ...

#### Modified Gravity and Cosmology

In this review we present a thoroughly comprehensive survey of recent work on modified theories of gravity and their cosmological consequences. Amongst other things, we cover General Relativity, Scalar-Tensor, Einstein-Aether, ...

#### An Improved Treatment of Optics in the Lindquist-Wheeler Models

We consider the optical properties of Lindquist-Wheeler (LW) models of the Universe. These models consist of lattices constructed from regularly arranged discrete masses. They are akin to the Wigner-Seitz construction of ...

#### The isotropic blackbody CMB as evidence for a homogeneous universe

(American Physical Society, 2012-08-01)

The question of whether the Universe is spatially homogeneous and isotropic on the largest scales is of fundamental importance to cosmology, but has not yet been answered decisively. Surprisingly, neither an isotropic ...

#### What the small angle CMB really tells us about the curvature of the Universe

It is well known that observations of the cosmic microwave background (CMB) are highly sensitive to the spatial curvature of the Universe, k. Here we find that what is in fact being tightly constrained by small angle ...

#### The Parameterised Post-Newtonian Limit of Bimetric Theories of Gravity

We consider the post-Newtonian limit of a general class of bimetric theories of gravity, in which both metrics are dynamical. The established parameterised post-Newtonian approach is followed as closely as possible, although ...

#### Hubble Diagram Dispersion From Large-Scale Structure

We consider the effects of large structures in the Universe on the Hubble diagram. This problem is treated non-linearly by considering a Swiss Cheese model of the Universe in which under-dense voids are represented as ...