Limiting alternative theories of gravity using gravitational wave observations across the spectrum

Understand

The advent of gravitational wave astronomy provides new proving grounds for testing theories of gravity.

• Recent work has reinvigorated the study of bimetric theories of gravity and massive gravity theories.
• One of the most interesting predictions of these theories, as well as some string theories, is the subluminal speed of propagating gravitational waves.
• Multi-messenger astronomy provides a unique opportunity to put limits on the difference (either positive or negative) between the propagation speed of electromagnetic and gravitational waves from these sources.