- 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.
- Indian Heaven Wilderness (wilderness.net)
A forested plateau dominated by fir (Pacific silver, noble, subalpine) opens often into meadows with at least 150 small lakes, ponds, and marshes. Most of the larger lakes contain rainbow and brook trout. Lava once flowed from almost every knobby rise above the plateau, which averages 4,500 feet in elevation…