Theorema Egregium, formulated by Carl Friedrich Gauss, states that the Gaussian curvature of a surface is an intrinsic property, meaning it is preserved under local isometric deformations. This implies that curvature can be determined entirely by the surface's metric, without reference to the surrounding space, highlighting a profound connection between geometry and topology.
Intrinsic geometry studies the properties of a geometric object that are invariant under isometries, focusing on the shape's internal structure rather than its external embedding. It is crucial in understanding the geometry of surfaces and manifolds from the perspective of an observer residing within the space itself.
A Riemannian metric is a smoothly varying positive definite inner product on the tangent space of a manifold, enabling the measurement of angles, lengths, and volumes. It is fundamental in the study of Riemannian geometry, providing the tools to define concepts such as geodesics, curvature, and distance on manifolds.
Geodesic curvature is a measure of how a curve deviates from being a geodesic on a given surface, quantifying the curve's bending relative to the surface's intrinsic geometry. It is essential in differential geometry for understanding the properties of curves on surfaces and plays a crucial role in the Gauss-Bonnet theorem, which relates geometry and topology.
Topology is a branch of mathematics that studies the properties of space that are preserved under continuous transformations such as stretching and bending, but not tearing or gluing. It provides a foundational framework for understanding concepts of convergence, continuity, and compactness in various mathematical contexts.