Circles, Spheres and Balls
In hyperbolic geometry the circumference of a circle of radius r is greater than 2πr. It is in fact equal to
The area of the enclosed disk is
The surface area of a sphere is
The volume of the enclosed ball is
For the measure of an n-1 sphere in n dimensional space the corresponding expression is
where the full n dimensional solid angle is
using for the Gamma function.
The measure of the enclosed n ball is:
Read more about this topic: Hyperbolic Geometry
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