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S Feb 10, 2019 at 23:41 history bounty ended Mike Shulman
S Feb 10, 2019 at 23:41 history notice removed Mike Shulman
Feb 10, 2019 at 23:41 vote accept Mike Shulman
Feb 10, 2019 at 6:29 answer added Reid Barton timeline score: 5
Feb 6, 2019 at 9:08 answer added Karol Szumiło timeline score: 8
S Feb 3, 2019 at 12:04 history bounty started Mike Shulman
S Feb 3, 2019 at 12:04 history notice added Mike Shulman Draw attention
Jan 31, 2019 at 9:38 answer added Mike Shulman timeline score: 5
Jan 31, 2019 at 9:31 comment added Mike Shulman Hmm, actually maybe that isn't quite enough: the large category we embed it in will still have $(A\otimes 1)\times Y \ncong A\otimes Y$, but it may not be cartesian closed. However, I've now constructed such a $D$, which seems to me to be a big step towards a negative answer, so I'll post it below.
Jan 31, 2019 at 6:09 comment added Mike Shulman @TheoJohnson-Freyd Maybe local presentability of $V$ might matter; but as I said, I'm happy to assume anything even up to its being a presheaf topos. Given $V$, though, I don't think local presentability of $C$ can matter: if it fails for some $C$, then it fails for some specific $A\in V$ and $Y\in C$, which means there is some small subcategory of $C$ in which it fails, and we can restrict to that subcategory and then embed it in a locally presentable $V$-category preserving the relevant limits and colimits to get a "good" $C$ where it still fails.
Jan 31, 2019 at 6:06 comment added Mike Shulman @TheoJohnson-Freyd Good point about $X=1$.
Jan 31, 2019 at 1:02 comment added Theo Johnson-Freyd Which is in turn equivalent to asking whether $(A\otimes 1) \times Y \overset?= A\otimes Y$, for $A \in V$ and $Y \in C$.
Jan 31, 2019 at 1:00 comment added Theo Johnson-Freyd It is not hard to reduce to the case $X=1$. Your question is equivalent to asking whether $C(Y,Z) \overset?= C(1,Z^Y)$.
Jan 31, 2019 at 0:59 comment added Theo Johnson-Freyd My spidey sense says that the only way this could fail would be for stupid set theoretic reasons, if your categories are too far from being locally presentable. (I don't make a wager about that case --- perhaps there are no set theoretic obstructions.) But I agree I cannot answer the question.
Jan 30, 2019 at 20:56 history asked Mike Shulman CC BY-SA 4.0