Relativity was one of the most important theories of the 20th century. When Einstein published the General Theory of Relativity in 1915, some concepts, such as 4-dimensional spacetime as a unified entity of space and time, relativity of simultaneity, and kinematic and gravitational time dilation, were created. Understanding the universe allowed us to launch satellites, improve navigation and bring people even more together. Since then, the connectivity concept has completely changed. But how exactly?
We have been venturing into space since October 4, 1957, when the Union of Soviet Socialist Republics (U.S.S.R.) launched Sputnik (the first satellite in orbit). NASA started its operations in 1958. Yuri Gagarin made one orbit around Earth in 1961, and Neil Armstrong was the first to be sent to the moon in 1969. This sequence of events during the Cold War contributed to the development of technologies such as the Navstar/GPS satellite in 1978, which was allowed for civil usage in 1983 after the Korean Air Lines Flight 007 disaster. Today, GPS accounts for all of the relativistic effects in order to work with precision, such as the consequences of the Earth’s gravitational field.