| − | '''Heliocentrism''' is the view that the sun is at the center of the universe. It was proposed by some ancient Greeks,<ref>Aristarchus of Samos (ca. 310-230 BC) proposed it, Archimedes discussed it, and the idea was well-known in Europe when [[Copernicus]] proposed a heliocentric model. [http://galileo.rice.edu/sci/theories/copernican_system.html]</ref> and became the dominant view in the 1700s and 1800s. It was generally abandoned in the 20th century.<ref>There's still some professor that teaches it in Ohio.</ref> | + | '''Heliocentrism''' is the view that the sun is at the center of the universe. It was proposed by some ancient Greeks,<ref>Aristarchus of Samos (ca. 310-230 BC) proposed it, Archimedes discussed it, and the idea was well-known in Europe when [[Copernicus]] proposed a heliocentric model. [http://galileo.rice.edu/sci/theories/copernican_system.html]</ref> and became the dominant view in the 1700s and 1800s. It was abandoned in the 20th century. |
| − | Since the advent of relativity theory in the early 1900s, the laws of physics have been written in [[covariance|covariant]] equations, meaning that they are equally valid in any frame. Heliocentric and geocentric theories are both used today, depending on which allows more convenient calculations. | + | Since the advent of relativity theory in the early 1900s, the laws of physics have been written in [[covariance|covariant]] equations, meaning that they are equally valid in any frame. Heliocentric and [[Geocentric theory|geocentric]] theories are both used today, depending on which allows more convenient calculations. |