Dold–Thom theorem

In algebraic topology, the Dold–Thom theorem, proved by Albrecht Dold and René Thom (1956, 1958), states that the homotopy group π_i(SP(X)) of the infinite symmetric product SP(X) of a connected CW complex X is the i-th singular reduced homology group of X, usually denoted by ${\displaystyle {\widetilde {H}}_{i}(X;\mathbb {Z} )}$.

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