513 citations · 6.8k across the 165 of their papers we have counts for
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Detecting Chameleons: The Astronomical Polarization Produced by Chameleon-like Scalar Fields
Clare Burrage, Anne-Christine Davis, Douglas J. Shaw
We show that a coupling between chameleon-like scalar fields and photons induces linear and circular polarization in the light from astrophysical sources. In this context chameleon…
f(R) Gravity and Chameleon Theories
Philippe Brax, Carsten van de Bruck, Anne-Christine Davis +1
We analyse f(R) modifications of Einstein's gravity as dark energy models in the light of their connection with chameleon theories. Formulated as scalar-tensor theories, the f(R) t…
Small Scale Structure Formation in Chameleon Cosmology
Philippe Brax, Carsten van de Bruck, Anne-Christine Davis +1
Chameleon fields are scalar fields whose mass depends on the ambient matter density. We investigate the effects of these fields on the growth of density perturbations on sub-galact…
Boundary Inflation and the WMAP Data
Christophe Ringeval, Philippe Brax, Carsten van de Bruck +1
Inflation in a five-dimensional brane world model with two boundary branes is studied. We make use of the moduli space approximation whereby the low energy theory reduces to a four…
Brane World Cosmology, the CMB and the Radion
A. -C. Davis, Ph. Brax, C. van de Bruck
Recent developments in the theory of extra dimensions have opened up avenues to confront such theories with cosmological tests. We discuss a brane-world model with a bulk scalar fi…
Chameleon Dark Energy
Ph. Brax, C. van de Bruck, A. C. Davis +2
Chameleons are scalar fields whose mass depends on the environment, specifically on the ambient matter density. While nearly massless in the cosmos, where the matter density is tin…
Is the radion a chameleon?
Ph. Brax, C. van de Bruck, A. -C. Davis
The chameleon mechanism is a way to give an effective mass to a light scalar field via field self-interaction and interaction with matter. We study this mechanism in models in whic…
Cosmological Perturbations During Radion Stabilization
P. R. Ashcroft, C. van de Bruck, A. -C. Davis
We consider the evolution of cosmological perturbations during radion stabilization, which we assume to happen after a period of inflation in the early universe. Concentrating on t…
Detecting Dark Energy in Orbit -- the Cosmological Chameleon
Philippe Brax, Carsten van de Bruck, Anne-Christine Davis +2
We show that the chameleon scalar field can drive the current phase of cosmic acceleration for a large class of scalar potentials that are also consistent with local tests of gravi…
Boundary Inflation in the Moduli Space Approximation
P. R. Ashcroft, C. van de Bruck, A. -C. Davis
The evolution of slow--roll inflation in a five--dimensional brane world model with two boundary branes and bulk scalar field is studied. Assuming that the inflationary scale is be…
CMB Anisotropies in the Presence of Extra Dimensions
C. S. Rhodes, C. van de Bruck, Ph. Brax +1
We discuss the effect of the time evolution of extra dimensions on CMB anisotropies and large-scale structure formation. We study the impact of scalar fields in a low-energy effect…
Gauge Coupling Variation in Brane Models
G. A. Palma, Ph. Brax, A. C. Davis +1
We consider the space-time variation of gauge couplings in brane-world models induced by the coupling to a bulk scalar field. A variation is generated by the running of the gauge c…
Inflationary Dynamics with Runaway Potentials
P. R. Ashcroft, C. van de Bruck, A. -C. Davis
The evolution of two slow--rolling scalar fields with potentials of the form is studied. Considering different values of the parameters , and ,…
Suppression of Entropy Perturbations in Multi--Field Inflation on the Brane
P. R. Ashcroft, C. van de Bruck, A. -C. Davis
At energies higher than the brane tension, the dynamics of a scalar field rolling down a potential are modified relative to the predictions of General Relativity. The modifications…
Natural Magnetogenesis from Inflation
K. Dimopoulos, T. Prokopec, O. Tornkvist +1
We consider the gravitational generation of the massive Z-boson field of the standard model, due to the natural breaking of its conformal invariance during inflation. The electrowe…
Large-Scale Primordial Magnetic Fields from Inflation and Preheating
Ola Tornkvist, Anne-Christine Davis, Konstantinos Dimopoulos +1
We consider models in which the (transverse) photon mass is non-zero during inflation and drops to zero non-adiabatically at the end of inflation. Through this process, vacuum fluc…
Primordial Spectrum of Gauge Fields from Inflation
Anne-Christine Davis, Konstantinos Dimopoulos, Tomislav Prokopec +1
We show that conformal invariance of gauge fields is naturally broken in inflation, having as a consequence amplification of gauge fields. The resulting spectrum of the field stren…
Dynamics and properties of chiral cosmic strings in Minkowski space
A. C. Davis, T. W. B. Kibble, M. Pickles +1
Chiral cosmic strings are produced naturally at the end of inflation in supersymmetric models where the symmetry is broken via a D-term. Consequently in such theories, where both i…
Relaxing the Bounds on Primordial Magnetic Seed Fields
Anne-Christine Davis, Matthew Lilley, Ola Tornkvist
We point out that the lower bound on the primordial magnetic field required to seed the galactic dynamo is significantly relaxed in an open universe or in a universe with a positiv…
On the Evolution of Primordial Magnetic Fields
K. Dimopoulos, A. C. Davis
A new mechanism for the evolution of primordial magnetic fields is described and analysed. The field evolution is followed from the time of its creation until the epoch of structur…
Nucleosynthesis Constraints on Defect-Mediated Electroweak Baryogenesis
Robert Brandenberger, Anne-Christine Davis, Martin J. Rees
In the defect-mediated electroweak baryogenesis scenario, baryons are produced in well separated regions of space. It is shown that between the electroweak phase transition at a te…
Electroweak Baryogenesis with Electroweak Strings
Robert H. Brandenberger, Anne-Christine Davis
If stable electroweak strings are copiously produced during the electroweak phase transition, they may contribute significantly to the presently observed baryon to entropy ratio of…