Definition

Let YY be a quasi-smooth derived scheme or stack, and let Sing(Y)\operatorname{Sing}(Y) be its classical scheme of singularities. The singular support of a coherent complex F\mathcal F is a closed conical subset

SS(F)Sing(Y)\operatorname{SS}(\mathcal F)\subseteq\operatorname{Sing}(Y)

defined by the action of cohomological operators associated with the derived normal directions of YY.

For a conical closed subset ZSing(Y)Z\subseteq\operatorname{Sing}(Y), the full subcategory IndCohZ(Y)\operatorname{IndCoh}_Z(Y) consists of whose singular support is contained in ZZ.

This derived-algebraic notion is distinct from the singular support of a distribution or the microsupport of a constructible sheaf.

References
  1. Dima Arinkin and Dennis Gaitsgory, “Singular support of coherent sheaves, and the geometric Langlands conjecture,” Selecta Mathematica 21 (2015), 1–199. arXiv.