Hyperbolic Geometry - Circles, Spheres and Balls

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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