matonski said:Here are video lectures as well as notes from those lecture by Sean Carroll
General Relativity is a theory of gravity developed by Albert Einstein in the early 20th century. It describes how massive objects, such as planets and stars, distort the fabric of space and time, causing the phenomenon of gravity.
Newton's theory of gravity is based on the concept of a force acting between two objects with mass. In contrast, GR explains gravity as the curvature of space and time caused by massive objects. GR also predicts more accurate results in extreme conditions, such as near black holes.
The equivalence principle states that the effects of gravity and acceleration are indistinguishable. In GR, this principle is extended to include the curvature of space and time. It is a fundamental concept in understanding the behavior of gravity in the theory.
GR is used in a wide range of applications in modern physics, including the study of cosmology and the behavior of black holes. It is also essential in the development of technologies such as GPS, which relies on precise calculations of time dilation due to gravity.
Aside from its use in modern physics and technology, GR has practical applications in fields such as astronomy, where it helps to predict the behavior of celestial objects. It also provides insights into the structure and evolution of the universe.