In mathematics, a connected submanifold of a compact manifold with boundary is said to be boundary parallel, ∂-parallel, or peripheral if it can be continuously deformed into a boundary component. This notion is important for 3-manifold topology.

Boundary-parallel embedded surfaces in 3-manifolds

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some more care is needed: admits a bicollar, is the frontier.

Context and applications

See also

• Atoroidal

• Satellite knot

References