To clarify, Einstein's theory of relativity, including his predictions regarding gravitational waves and black holes, has not been disproven. In fact, Einstein's theories have been extensively tested and have consistently withstood experimental and observational scrutiny.
Einstein's general theory of relativity, published in 1915, provides a description of gravity as the curvature of spacetime caused by massive objects. It predicted the existence of gravitational waves, which are ripples in the fabric of spacetime caused by accelerating massive objects. These predictions were confirmed in 2015 when the Laser Interferometer Gravitational-Wave Observatory (LIGO) detected gravitational waves for the first time. Since then, numerous gravitational wave detections have provided further evidence in support of Einstein's theory.
Regarding black holes, Einstein's theory of general relativity allows for their existence. Black holes are regions of spacetime with extremely strong gravitational forces, where matter is compressed into a singularity. While direct observations of black holes were challenging in the past, advancements in observational techniques, such as the Event Horizon Telescope, have now provided compelling evidence for the existence of black holes. The first direct image of a black hole's event horizon was obtained in 2019, aligning with the predictions of Einstein's theory.
It's worth noting that scientific theories are continually refined and expanded as new evidence emerges. However, at present, Einstein's theory of relativity remains the foundation for our understanding of gravity and has not been disproven in regard to gravitational waves and black holes.