Probing modified gravity theories and cosmology using gravitational-waves and associated electromagnetic counterparts

Inflationary Cosmology in Modified Gravity Theories

We review inflationary cosmology in modified gravity such as R gravity with its extensions in order to generalize the Starobinsky inflation model. In particular, we explore inflation realized by three kinds of effects: modification of gravity, the quantum anomaly, and the R term in loop quantum cosmology. It is explicitly demonstrated that in these inflationary models, the spectral index of sca...

Generating Electromagnetic Waves from Gravity Waves in Cosmology

Examples of test electromagnetic waves on a Friedmann–Lemâıtre– Robertson–Walker (FLRW) background are constructed from explicit perturbations of the FLRW space–times describing gravitational waves propagating in the isotropic universes. A possible physical mechanism for the production of the test electromagnetic waves is shown to be the coupling of the gravitational waves with a test magnetic ...

Probing strong-field gravity and black holes with gravitational waves

Gravitational wave observations will be excellent tools for making precise measurements of processes that occur in very strong-field regions of spacetime. Extreme mass ratio systems, formed by the capture of a stellar mass body compact by a massive black hole, will be targets for planned space-based interferometers such as LISA and DECIGO. These systems will be especially powerful tools for tes...

Modified gravity and cosmology

Finding and Using Electromagnetic Counterparts of Gravitational Wave Sources

The principal goal of this whitepaper is not so much to demonstrate that gravitational wave detectors like LIGO and LISA will help answer many central questions in astronomy and astrophysics, but to make the case that they can help answer a far greater range of questions if we prepare to make the (sometimes substantial) effort to identify electromagnetic counterparts to the gravitational wave s...