In 1609, German astronomer Johannes Kepler established Kepler's laws of planetary motion, which later influenced Newton's theory of universal gravitation.

In 1632, Galileo Galilei introduced Galilean relativity, stating that the laws of physics are the same in all inertial frames. He used the example of a ship moving at constant velocity on a smooth sea to illustrate this concept.

In 1634, Italian physicist Galileo Galilei made significant contributions to the understanding of motion on inclined planes and falling bodies, laying the groundwork for Newton's theory of gravity.

In 1687, Sir Isaac Newton published the Principia, introducing Newton's Laws of Motion. Newton was not aware at the time that his laws were only correct for low-speed moving objects.

Hendrik Antoon Lorentz, a Dutch physicist, derived the transformation equations that were later utilized by Albert Einstein in formulating the Special Theory of Relativity.

Abraham's 1902 model of electromagnetic mass was one of the early contributions to the understanding of mass-energy equivalence, laying the groundwork for future developments in the theory of relativity.

In 1904, various scientists including Abraham, Lorentz, Bucherer, and Langevin proposed models of electromagnetic mass, which contributed to the development of Einstein's special theory of relativity.

Albert Einstein introduced his special theory of relativity, which revolutionized the understanding of space, time, and the relationship between energy and mass.

In 1906, Alfred Bucherer introduced the term 'theory of relativity' based on Max Planck's concept of relative theory.

In 1907, Albert Einstein began working on a theory that would incorporate gravity into his previous work on special relativity, leading to the development of his general theory of relativity.

Hermann Minkowski's geometrization of special relativity allowed Einstein to progress beyond his equivalence principle.

In 1911, Albert Einstein published an article expanding on his previous work, where he considered the case of a uniformly accelerated box not in a gravitational field. He used special relativity to show that time passes differently at different positions in a gravitational field.

In 1912, astronomer Charles D. Perrine and the Cordoba team attempted to observe light deflection during a solar eclipse in Brazil. They were the only expedition to construct specialized equipment for this purpose, borrowing intramercurial camera lenses from the Lick Observatory.

In 1913, while collaborating with Marcel Grossmann in Zurich, Albert Einstein made significant progress in reformulating gravity. Leveraging geometrical concepts from the mid-1800s, Einstein created a novel and rigorous approach to gravity based on the geometry of space and time.

In 1914, Albert Einstein published his Theory of Special Relativity, introducing groundbreaking concepts that reshaped the understanding of space and time.

Albert Einstein published his general theory of relativity, which describes gravity as a curvature in the fabric of spacetime caused by mass and energy.

On November 13, 1915, Albert Einstein received an invitation from David Hilbert to join him in Göttingen to discuss the 'solution to your great problem.' Einstein declined due to fatigue and stomach pains.

On November 19, 1915, Albert Einstein received Hilbert's manuscript in the mail, which closely resembled Einstein's own recent work. Einstein expressed his irritation at the similarity of the systems.

In November 1915, Albert Einstein announced the completion of his general theory of relativity at the Prussian Academy of Sciences in Berlin. This marked a significant milestone in his intellectual journey, reshaping our understanding of gravity, space, time, matter, and energy.

Albert Einstein formulated the equivalence principle, stating that the effects of gravity are indistinguishable from the effects of acceleration.

In 1917, Albert Einstein applied his theory of relativity to the universe as a whole, establishing the foundation of relativistic cosmology. He introduced the cosmological constant to maintain a static universe.

Arthur Eddington's expedition confirmed the bending of light around the Sun during a solar eclipse, providing experimental evidence for Einstein's general theory of relativity.

Einstein's General Theory of Relativity was confirmed through observations during a solar eclipse. The prediction that beams of light emitted by distant stars would travel along curved trajectories as they passed through the warped region near the Sun was tested successfully.

In 1922, Alexander Friedmann found a solution that suggested the universe may expand or contract, contributing to the understanding of the expanding universe.

In 1927, Georges Lemaître, a Belgian astronomer and priest, discovered non-static cosmological solutions to Einstein's equations, describing an expanding universe without the need for the cosmological constant. He also theoretically derived Hubble's law.

In 1929, Edwin Hubble provided evidence for the expansion of the universe, leading to Einstein abandoning the cosmological constant. This discovery marked a significant shift in our understanding of the cosmos.

Rosen's bimetric theory suggested modifications to the field equations of general relativity, but was refuted by observations of binary pulsars due to the presence of bipolar gravitational radiation.

In 1948, American physicist Howard Percy Robertson created a test theory to demonstrate the validity of the Special Theory of Relativity.

Albert Einstein passed away in America in 1955.

In 1957, Martin Kruskal's proof based on the Schwarzschild solution demonstrated the existence of black holes, a concept initially doubted by Einstein. This breakthrough significantly contributed to the field of astrophysics.

In 1960, American mathematician and physicist Martin Kruskal unveiled the complete classical spacetime structure of the simplest form of a black hole within the framework of General Relativity.

The Brans–Dicke theory, also known as scalar–tensor theory, proposed changes to the field equations of general relativity. It includes a tunable parameter ω, where ω = ∞ is equivalent to general relativity.

Stephen Hawking, the English theoretical physicist, made a significant theoretical breakthrough in 1974 by proposing that black holes emit radiation, now known as Hawking radiation.

In 1986, M.N. Macrossan wrote a note discussing the concept of relativity before Einstein in the British Journal of Philosophy of Science.

In 2011, the team behind Gravity Probe B announced the successful conclusion of the half-century-long experiment, confirming that the gyroscopes' axes were turning as predicted by Einstein's math.

In 2012, the anomaly in neutrino speed was attributed to a failure of the equipment, which was officially reported, resolving the initial challenge to the theory of relativity.

The LIGO experiment detected gravitational waves for the first time, confirming a key prediction of Einstein's general theory of relativity.

One hundred years ago, Albert Einstein completed his general theory of relativity, which revolutionized the understanding of gravitation as an inherent property of space and time. This marked a significant milestone in Einstein's life as a physicist.

The neutron-star merger event GW170817 helped constrain the possible deviations of Brans–Dicke theory from general relativity through detailed analyses.