Seonglae Cho직선의 개념을 굽은 공간으로 일반화한 것
generalized shortest path for curved space
Why Gravity is not a force | Uncovering the Law of Gravity | Explained with General Relativity
What is gravity? Newton and Einstein provided distinct theories to answer this question. Newton told us gravity is a force, while Einstein taught us that gravity is not a force. But what does this really mean? In this video I explain the difference between "acceleration" and "force" by introducing the concept of "freefall" and "equivalence principle".
https://www.youtube.com/watch?v=cbLRF-XY-b0
