Example image of eyePlorer eyePlorer map for 'Homology sphere': Algebraic topology Betti number Connected space Homology (mathematics) Sphere Fundamental group Hurewicz theorem Perfect group Simply connected space Henri Poincaré 3-sphere Spherical 3-manifold Binary icosahedral group Poincaré conjecture Dodecahedron Quotient space Alternating group Hyperbolic 3-manifold Icosahedral symmetry Rotation group Seifert-Weber space Symmetry group Covering space Homeomorphism Quaternion Covering group Embedding Dehn surgery Trefoil knot Cosmic microwave background radiation Jean-Pierre Luminet Paris Observatory Shape of the Universe Wilkinson Microwave Anisotropy Probe Prime decomposition (3-manifold) Seifert fiber space Geometrization conjecture SL₂(R) Rokhlin's theorem Casson invariant Homology manifold Suspension (topology) Topological manifold Piecewise linear manifold Triangulation (topology) Simplicial complex If and only if Link (geometry) Annals of Mathematics Robion Kirby