Topology

English: Topology is a branch of mathematics studying those properties of a geometric figure or solid that are not changed by stretching, bending and similar homeomorphisms.

See also Topology (Network).

Four Color Theorem

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  Four Color Theorem

Knot Theory

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  Knot ornament on closed gate of mathematics department at night

Separation axioms

Hierarchy of separation axioms

Regularity separation axiom

Normal separation axiom

Hausdorff Space

Homeomorphism

See also Homeomorphism

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  Classical example of homeomorphism using a torus and a coffee mug

Möbius strip

See also Moebius Strip and Category:Moebius strip.

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