Commutative ring spectrum

In the mathematical field of algebraic topology, a commutative ring spectrum, roughly equivalent to a ${\displaystyle E_{\infty }}$-ring spectrum, is a commutative monoid in a good category of spectra.

The category of commutative ring spectra over the field ${\displaystyle \mathbb {Q} }$ of rational numbers is Quillen equivalent to the category of differential graded algebras over ${\displaystyle \mathbb {Q} }$.

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