Exploring strong-field deviations from general relativity via gravitational waves

Understand

Two new observational windows have been opened to strong gravitational physics: gravitational waves, and very long baseline interferometry.

• This suggests observational searches for new phenomena in this regime, and in particular for those necessary to make black hole evolution consistent with quantum mechanics.
• We describe possible features of "compact quantum objects" that replace classical black holes in a consistent quantum theory, and approaches to observational tests for these using gravitational waves.
• This is an example of a more general problem of finding consistent descriptions of deviations from general relativity, which can be tested via gravitational wave detection.