Skip to main content
7 events
when toggle format what by license comment
Mar 10, 2019 at 16:53 vote accept Phil-W
Mar 10, 2019 at 10:11 answer added Jeremy Rickard timeline score: 13
Mar 9, 2019 at 23:44 comment added Gro-Tsen It is probably worth linking to the analogous question for modules over a (commutative) ring: it turns out, as explained in several answers there, that the map $M^\vee\otimes N^\vee\to(M\otimes N)^\vee$ can fail to be injective (even in the presence of AC, that is).
Mar 9, 2019 at 23:24 history edited YCor CC BY-SA 4.0
edited body
Mar 9, 2019 at 23:11 comment added Phil-W My question can be broadly intepreted as : what is the status of those statements in ZF ? Are they theorems ? are they equivalent to AC ? are they equivalent to a known weaker axiom ?
Mar 9, 2019 at 23:03 comment added YCor "Is AC necessary to prove X" technically means "does X implies AC" (probably, in ZF). But this is probably not what you mean. Probably you're asking whether the given statement is a theorem of ZF.
Mar 9, 2019 at 22:54 history asked Phil-W CC BY-SA 4.0