Moduli stack of elliptic curves

In mathematics, the moduli stack of elliptic curves, denoted as M 1 , 1 {\displaystyle {\mathcal {M}}_{1,1}} or M e l l {\displaystyle {\mathcal {M}}_{\mathrm {ell} }} , is an algebraic stack over Spec ( Z ) {\displaystyle {\text{Spec}}(\mathbb {Z} )} classifying elliptic curves. Note that it is a special case of the moduli stack of algebraic curves M g , n {\displaystyle {\mathcal {M}}_{g,n}} .

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