maths.free › Differential Geometry
Differential Geometry
Curves, surfaces, curvature, manifolds: the language of general relativity.
Lessons
integrate sqrt(1 + 4x^2) dx from 0 to 1
Advanced
Surfaces and Gaussian curvature
Principal curvatures, Gauss's Theorema Egregium, geodesics.
x^2 - y^2
Calculus on curved things. Curvature measures how a surface bends, geodesics are its straight lines, and manifolds let the same ideas run in any dimension. Einstein's equations are a statement in this language.
More lessons
Curves
Surfaces
Manifolds
Some of these lessons are adapted from open texts: Wikipedia. Each lesson page names its source and licence.
Symbols used here
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Questions people ask
What is curvature?
For a curve, how fast its direction turns per unit length; for a surface, Gauss's combination of the two principal bendings, and Gauss's theorem says it can be measured from inside the surface without leaving it.
Type it or draw it on the solver page: every step, a picture, the answer hidden until you ask. Solve →
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