The Journey Through Time
How we went from "things fall because they seek their natural place" to "spacetime tells matter how to move."
The Chapters
Each chapter covers a turning point in gravitational physics: why the old theory broke, what replaced it, and the experiments that settled the debate.
The Greeks and Celestial Spheres
400 B.C. - 150 A.D.
How Aristotle and Ptolemy imagined a universe of perfect crystalline spheres.
The Copernican Revolution
1473 - 1642
Copernicus, Tycho Brahe, and Kepler redefine the cosmos.
Newton and Universal Gravitation
1642 - 1727
The force that governs apples and planets: modern physics is born.
Limits of Newtonian Gravity
1859 - 1905
Mercury disobeys, and light travels too fast.
Special Relativity
1905-1908
Einstein destroys absolute time and prepares the revolution.
Birth of General Relativity
1854-1915
The mathematical revolution that reimagined gravity as geometry.
Modern Differential Geometry
Mathematical Foundations
Fiber bundles, connections, curvature tensors: the modern geometric framework that unifies GR and gauge theories.
Verifications and Renaissance
1919-1975
The eclipse that made Einstein famous, and the rebirth of relativity.
Black Holes
1916 - 2022
From Schwarzschild's mathematical solution to the first photograph of a black hole shadow - the journey of the most extreme objects in the universe.
Gravitational Waves
1916-2025
100 years after Einstein predicted ripples in spacetime, LIGO finally heard two black holes collide.
Cosmology
1917 - Present
How General Relativity revealed the history, structure, and fate of the entire universe—from the Big Bang to the accelerating expansion.
Numerical Relativity
1959 - Present
For forty years, physicists failed to simulate black holes colliding. Then, in 2005, two breakthroughs cracked the problem—just in time for LIGO.
Quantum Gravity
1930 - Present
The quest to unify General Relativity with Quantum Mechanics remains physics' greatest unsolved problem. From Wheeler-DeWitt to string theory and loop quantum gravity.
Wormholes and ER=EPR
1935 - Present
From Einstein-Rosen bridges to the mind-bending ER=EPR conjecture: are entangled particles connected by microscopic wormholes?
Advanced Mathematics
Fiber bundles, differential forms, and the Hilbert action for those who want more.
About This Timeline
Click on any available chapter to read the history and play with the simulations. New chapters are added as they're ready.