In 1916
No but others have.
He asked God.
You tell me.
Einstein didn't prove the theory of relativity. It is a theory, a possible explanation, it is generally accepted because it explains a lot of things but that doesn't "prove" the theory, at least not to physicists. See related questions for the country of discovery.
The Einstein Theory of Relativity was developed by Albert Einstein in 1905. This theory introduced the concepts of special relativity and general relativity, revolutionizing our understanding of space, time, and gravity.
It is used to prove some of the statements used in Einstein's The general Theory of relativity
Albert Einstein developed the theory of relativity while working as a patent clerk in Bern, Switzerland in 1905. He published his theory in a paper titled "On the Electrodynamics of Moving Bodies." This groundbreaking work revolutionized our understanding of space, time, and gravity.
Albert Einstein published the works now referred to as Special Relativity in 1905 and General Relativity in 1916.
Special Relativity 1905General Relativity completed 1915 and published 1916At the time Einstein was about 40 years old
Albert Einstein developed the theory of relativity.
Albert Einstein proposed the theories of relativity.
Relativity.