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Results tagged with at.algebraic-topology
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user 3384
Homotopy theory, homological algebra, algebraic treatments of manifolds.
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Degree 2 branched map from the torus to the sphere
One example: lay your $g$-holed torus $T$ out flat and draw a line the long way through each hole. It hits the torus in $2g + 2$ points. Consider the 180 degree rotation $w$ through that line. Now con …
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