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Quotient "spaces":

While quotients, e.g. of group actions, in geometry often are degenerate, several generalized notions of quotient or of space help here: Sheaf quotients, Orbifolds, Algebraic Spaces, Stack quotients, Homotopy quotients, Non-commutative quotients, GIT quotients, ...

(similarly with moduli spaces)

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Quotient "spaces":

While quotients, e.g. of group actions, in geometry often are degenerate, several generalized notions of quotient or of space help here: Sheaf quotients, Orbifolds, Algebraic Spaces, Stack quotients, Homotopy quotients, Non-commutative quotients, GIT quotients, ...

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Quotient "spaces":

While quotients, e.g. of group actions, in geometry often are degenerate, several generalized notions of quotient or of space help here: Sheaf quotients, Orbifolds, Algebraic Spaces, Stack quotients, Homotopy quotients, Non-commutative quotients, ...