Einstein's Special and General Relativity (1905 and 1915)

Einstein's relativity reshaped our understanding of space, time, and gravity. Special relativity established that light speed is constant and mass-energy equivalence (E=mc²). General relativity redefined gravity as spacetime curvature, predicting black holes and gravitational waves—LIGO confirmed these waves in 2016, a century later. GPS satellites require daily relativistic corrections, embedding Einstein's equations into every smartphone. This theory outperforms Newtonian physics in extreme conditions, such as near black holes, where it predicts time dilation precisely. A concrete data point: general relativity's predictions match observations to within 0.001% in solar system tests, as shown by the 1919 eclipse bending starlight.