## Search

Now showing items 1-10 of 41

#### The Method of Images in Cosmology

We apply the method of images to the exact initial data for cosmological models that contain a number of regularly arranged discrete masses. This allows us to join cosmological regions together by throats, and to construct ...

#### Piecewise Silence in Discrete Cosmological Models

We consider a family of cosmological models in which all mass is confined to a regular lattice of identical black holes. By exploiting the reflection symmetry about planes that bisect these lattices into identical halves, ...

#### On the Emergence of Accelerating Cosmic Expansion in f(R) Theories of Gravity

We consider cosmological modelling in $f(R)$ theories of gravity, using both top-down and bottom-up constructions. The top-down models are based on Robertson-Walker geometries, and the bottom-up constructions are built by ...

#### 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 ...

#### Perturbation Theory in Lemaitre-Tolman-Bondi Cosmology

The Lemaitre-Tolman-Bondi solution has received much attention as a possible alternative to Dark Energy, as it is able to account for the apparent acceleration of the Universe without any exotic matter content. However, ...

#### A Simple Model for Pulse Profiles from Precessing Pulsars, with Special Application to Relativistic Binary PSR B1913+16

(American Astronomical Society, 2008-05-31)

We study the observable pulse profiles that can be generated from precessing pulsars. A novel coordinate system is defined to aid visualization of the observing geometry. Using this system we explore the different families ...

#### 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 ...

#### Properties of Black Hole Radiation From Tunnelling

We consider the space-time associated with the evaporation of a black hole by quantum mechanical tunnelling events. It is shown that the surface through which tunnelling occurs is distinct from the global event horizon, ...

#### 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 ...