**"Relativity theory" is one of the theories in physics, which was proposed by Albert Einstein. Based on the principle that the speed of light is constant, relativity theory reconstructs physics, and fundamentally changes the conventional concepts of time, space, and the mass of objects. In particular, the "relativity of time" and the "relativity of space" demonstrated by relativity theory differ from our everyday recognition. Time is considered to pass at different speeds depending on the motion of an object, and space is also deformed by movement. It has also been demonstrated that mass and energy are equivalent, and the well-known equation "E = mc²" was derived. Relativity theory has had a significant impact on the fields of physics and cosmology, and has also contributed to the development of modern science and technology, as well as astronomy.** - Upscaled by <@1089335767253397504> (fast)
Relativity theory is one of the theories in physics, which was proposed by Albert Einstein. Based on the principle that the speed of light is constant, relativity theory reconstructs physics, and fundamentally changes the conventional concepts of time, space, and the mass of objects. In particular, the relativity of time and the relativity of space demonstrated by relativity theory differ from our everyday recognition. Time is considered to pass at different speeds depending on the motion of an object, and space is also deformed by movement. It has also been demonstrated that mass and energy are equivalent, and the wellknown equation E  mc² was derived. Relativity theory has had a significant impact on the fields of physics and cosmology, and has also contributed to the development of modern science and technology, as well as astronomy.