Normed idempotence of spectra and distributivity in equivariant higher algebra

Abstract: We introduce and develop the theory of distributivity for base categories equipped with so-called atomic orbital subcategories, with an eye towards applications in equivariant homotopy theory. This extends the important framework in Nardin's thesis and supplies several crucial details on distributivity missing from the treatment therein. As our main technical result, we provide a parametrised distributive version of the universal property of "partial cocompletions with relations". We then employ this to construct a distributively normed symmetric monoidal structure on presentable categories. In turn, by specialising to the case of equivariant homotopy theory for compact Lie groups G, we show that the category of genuine G-spectra is normed idempotent, so that we obtain the structure of multiplicative norms on G-spectra along inclusions of finite index subgroups.