Spontaneous-scalarization-induced dark matter and variation of the gravitational constant
Journal
Physical Review D
Journal Volume
92
Journal Issue
12
Pages
124016
Date Issued
2015
Author(s)
Abstract
We propose a new scalar-tensor model which induces significant deviation from general relativity inside dense objects like neutron stars, while passing the Solar System and terrestrial experiments, extending a model proposed by Damour and Esposito-Farese. Unlike their model, we employ a massive scalar field, dubbed the ``asymmetron,'' that not only realizes proper cosmic evolution but can also account for the cold dark matter. In our model, the asymmetron undergoes spontaneous scalarization inside dense objects, which results in the reduction of the gravitational constant by a factor of order unity. This suggests that observational tests of the constancy of the gravitational constant in the high-density phase are effective ways to study the asymmetron model.
Type
journal article