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Aug 5 at 1:43 comment added Mozibur Ullah @BenMcKay: And finally, drawing means we are describing extrinsically.
Aug 5 at 1:42 comment added Mozibur Ullah @Ben McKay: Plus the OP says "but I would like to find good ways to visually depict the notion of curvature". There is no mention of intrinsic here.
Aug 5 at 1:39 comment added Mozibur Ullah @Ben McKay: You can always embed a Riemann manifold in flat space.
Nov 20, 2020 at 8:13 comment added Sebastian @Ben McKay: It is not quite true for mean curvature: taking orientation into account, there exists for all $H\in\mathbb R$ oriented spheres with mean curvature $H$, where we take the plane for $H=0$. In fact, this leads to the mean curvature sphere congruence of a immersed surface in 3-space, which plays an important role in the investigation of Willmore surfaces. But of course, this concerns the extrinsic geometry of the surface and not the intrinsic geometry.
Nov 19, 2020 at 16:58 comment added Ben McKay Approximation by ellipsoids will not give you the Gauss or the mean curvature, as there is no approximating ellipsoid with the correct values for those, on some surfaces.
Nov 19, 2020 at 15:41 comment added Gabe K I don't see how gauge theory and (co)homology relate to extrinsic curvature. However, you are correct that there are many situations that extrinsic geometry is important. Nonetheless, the reason I was asking about intrinsic curvature is that it's much more difficult to visualize than extrinsic geometry. For instance, it's not hard to show that tori admit a flat metric, but most students' image of a donut is not flat (and you can't embed a flat donut smoothly in ℝ3).
Nov 19, 2020 at 15:37 comment added user44143 The book is not by Hilbert alone!
Nov 19, 2020 at 15:13 history edited Mozibur Ullah CC BY-SA 4.0
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Nov 19, 2020 at 14:33 history edited Mozibur Ullah CC BY-SA 4.0
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Nov 19, 2020 at 7:54 comment added Ben McKay The problem is really about curvature of Riemannian manifolds, not of the embedding of an embedded submanifold in Euclidean space, which is really very different.
Nov 19, 2020 at 7:08 history answered Mozibur Ullah CC BY-SA 4.0