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Nov 19, 2021 at 0:27 history edited David Roberts CC BY-SA 4.0
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Jul 27, 2017 at 19:57 comment added Chris Schommer-Pries The "module categories are categories of modules" yoga is probably very special to the finite rigid setting. We tried to be careful about what exactly was needed for this here:arxiv:1406.4204. An interesting example is the following (non-rigid) tensor category C. It is finite, semisimple and has two simple objects 1 and x. The object 1 is the unit and we have $x \otimes x = 0$. This determines the monoidal structure by linearity. If I remember right, the subcategory generated by x is a module category which is not of the form A-mod(C) for an algebra A in C.
Jul 27, 2017 at 19:47 comment added Chris Schommer-Pries The Deligne tensor product doesn't exist for arbitrary abelian categories. But if you relax "abelian" to instead mean "has finite colimits" then there is a very general tensor product that always exists called the "Kelly tensor product". A similar statement for locally presentable categories is in Cor 2.2.5 of (arXiv:1105.3104). I think the categorical machinery underlying these results can be adapted to the case of tensor products of module cats in the generality you are considering, but I don't know of a reference that does it.
Nov 25, 2009 at 18:09 comment added Evan Jenkins An Azumaya algebra is one in which the tensor actions $X \mapsto A \otimes X$ and $X \mapsto X \otimes A$ are equivalences between $\mathcal{C}$ and the categories of left $A \otimes A^{\text{op}}$-modules and right $A^{\text{op}} \otimes A$-modules, respectively. This definition comes from the paper by Van Oystaeyen and Zhang, "The Brauer Group of a Braided Monoidal Category."
Nov 25, 2009 at 7:23 comment added Reid Barton Could you recall the definition of Azumaya algebra in a general braided monoidal category?
Nov 25, 2009 at 7:08 history asked Evan Jenkins CC BY-SA 2.5