- “Groundhog Day” is a film that finds its note and purpose so precisely that its genius may not be immediately noticeable. It unfolds so inevitably, is so entertaining, so apparently effortless, that you have to stand back and slap yourself before you see how good it really is.
- n-body problem (Wikipedia)
In physics, the n-body problem is the problem of predicting the individual motions of a group of celestial objects interacting with each other gravitationally. Solving this problem has been motivated by the desire to understand the motions of the Sun, Moon, planets, and visible stars. In the 20th century, understanding the dynamics of globular cluster star systems became an important n-body problem. The n-body problem in general relativity is considerably more difficult to solve due to additional factors like time and space distortions.