constant negative curvature

Constant negative curvature describes a space where, at every point, the geometry behaves like a saddle shape. Unlike a flat surface (zero curvature) or a sphere (positive curvature), this space curves inward in every direction, causing parallel lines to diverge. It’s a characteristic of hyperbolic geometry, where the usual rules of Euclidean geometry don't apply. Think of it as a universe where the rules for shapes and distances are stretched in consistent ways, resulting in a space that expands faster than flat geometry as you move outward.