Is relativity just hand-waving, or is it a theory? It’s a theory, because it provided ways to experiment, to TEST whether it’s a more accurate view of the universe. Really ? Name 3 experiments or observations which confirm relativity ideas.

Sir Arthur Eddington travels to Africa in 1919 to observe occultation during a total solar eclipse.

In general relativity, precession, precession or change of orientation of the orbital ellipse within its orbital plane, is explained by gravitation being mediated by the curvature of spacetime. Einstein showed that general relativity agrees closely with the observed amount of perihelion shift in Mercury’s orbit. This was a powerful factor motivating the adoption of general relativity.

Einstein’s Cross

Hafele and Keating Experiment "During October, 1971, four cesium atomic beam clocks were flown on regularly scheduled commercial jet flights around the world twice, once eastward and once westward, to test Einstein's theory of relativity with macroscopic clocks. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40+/-23 nanoseconds during the eastward trip and should have gained 275+/-21 nanoseconds during the westward trip

Relativistic effects on GPS atomic clocks? General Relativity (GR) predicts that clocks in a stronger gravitational field will tick at a slower rate. Special Relativity (SR) predicts that moving clocks will appear to tick slower than non- moving ones. Clocks at any altitude above sea level do tick faster than clocks at sea level; and clocks on rocket sleds do tick slower than stationary clocks.