Strong field tests of gravity with electromagnetic and gravitational waves

Understand

For nearly a century, Einstein's theory of gravity has been the standard theory for describing gravitational phenomena in our universe.

• Along with its successes, limitations of the theory from theoretical (e.g., singularities) and observational (e.g., dark matter/energy) perspectives have appeared.
• This has led to proposals that modify or supersede Einstein's theory, and testing these theories against data, especially in the strong-field regime, has emerged as a new paradigm in physics in recent years.
• Along with the completely new avenue of gravitational waves, new and improved techniques based on electromagnetic waves are being used to test general relativity (GR) ever more stringently.