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Detecting dark energy in orbit: The cosmological chameleon
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 gravity. These provide
Unified description of screened modified gravity.
We consider modified gravity models driven by a scalar field whose effects are screened in high density regions due to the presence of nonlinearities in its interaction potential and/or its coupling
Brane world cosmology
Recent developments in the physics of extra dimensions have opened up new avenues to test such theories. We review cosmological aspects of brane world scenarios such as the Randall–Sundrum brane
f(R) gravity and chameleon theories
We analyze 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) theories imply the
Scalar fields, strongly coupled to matter, can be present in nature and still be invisible to local experiments if they are subject to a screening mechanism. The symmetron is one such mechanism that
Relaxing the bounds on primordial magnetic seed fields
Department of Applied Mathematics and Theoretical Physics, University of Cambridge,Silver Street, Cambridge CB3 9EW, United Kingdom(March 27, 1999)We point out that the lower bound on the primordial
Formation and interactions of topological defects
Topological defects, the unavoidable result of many symmetry-breaking phase transitions, can reveal the properties of many condensed matter systems, may be responsible for seeding the density
Shape dependence of Vainshtein screening
Scalar field theories that possess a Vainshtein mechanism are able to dynamically suppress the associated fifth forces in the presence of massive sources through derivative nonlinearities. The