# Manifold > [[PORTAL_Dynamical_system|Dynamical system]] spine. ## Microsims — three.js <div class="microsim-player"> <iframe src="https://wikitube-3d-microsims.netlify.app/Manifold_microsim.html" width="100%" height="520" frameborder="0" loading="lazy" sandbox="allow-scripts allow-same-origin" title="Manifold — three.js microsim"></iframe> </div> <p class="wt-pending"><strong>Note:</strong> staged, awaiting CDN deploy.</p> A manifold is a space that looks locally like ordinary flat Euclidean space at every point, even though its overall, global shape may be curved or connected in ways flat space cannot be. A circle, a sphere's surface, and a torus's surface are all manifolds: zoom in far enough on any point of any of them and the neighbourhood looks like a flat line or plane, even though the whole object is curved. ## Overview This build renders several standard manifolds — sphere, torus, Klein bottle among them — so the "locally flat, globally curved" idea can be explored by direct manipulation rather than taken on faith. Manifolds are the natural setting for a great deal of modern physics and mathematics: the state space of almost any [[Dynamical_system|dynamical system]] with continuous variables is a manifold, general relativity models spacetime itself as a four-dimensional manifold, and Hamiltonian mechanics' phase space carries the extra structure of a [[Symplectic_manifold|symplectic manifold]]. A [[Surface_(topology)|surface]] is simply the two-dimensional case. **On the spine:** [[Dynamical_system]] · [[Symplectic_manifold]] · [[Surface_(topology)]] · [[Geodesic]]. ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Manifold) : [Wikitube](https://en.wikitube.io/wiki/Manifold) --- *Repopulated 2026-08-05 · existing three.js asset renamed + wired, Wikipedia-sourced overview · 0 deletions.*