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1h
comment Topological spaces without homeomorphisms?
This doesn't seem like a good analogue of primeness. Why not ask about spaces $X$ which aren't homeomorphic to $Y\times Z$ for any $Y,Z$?
1d
comment Geometric Morphism
This is pretty vague. It seems like you sort of want an explanation of how logic is done in a topos, which is too large of a question. There aren't any easier textbooks that really do topos theory, but you might get something out of Lawvere and Achanuel's Sets for Mathematics, which essentially works in a topos to develop elementary set theory.
2d
revised Replacing faces of a cube in a quasicategory
edited tags
Apr
25
revised What is wrong with this proposed proof of the twin prime conjecture?
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Apr
25
comment Can I ask about copyright here?
Thanks for the more precise answer!
Apr
25
comment Can I ask about copyright here?
@Wore meta is for questions about stackexchange itself. So "can I ask about copyright here" is appropriate for meta, but "is the kind of blog I'm thinking of on shaky legal ground" is not.
Apr
25
answered Can I ask about copyright here?
Apr
25
answered Simplicial homotopy's exponential law
Apr
23
answered Subcategory of category of Module satisfies SSA?
Apr
22
comment adjoint functor and subcategories
Yeah, that's right.
Apr
22
comment Difference between the set of generators and the alphabet of a free group
No, any semi group can be presented by generators and relations, and as soon as there are any relations the semi group is not free. Your writing is very hard to read. Consider editing for concision.
Apr
22
comment Extension Operator.
How could there be such an operator, when there are in general many extensions of $B by $A$?
Apr
22
answered Presheaf and copresheaf categories on finite sets
Apr
22
answered adjoint functor and subcategories
Apr
22
comment adjoint functor and subcategories
Probably not Freyd-Mitchell. You want the special and the general adjoint functor theorems.
Apr
21
comment Non-monadic adjunction
And magically, as soon as you pass to the spaces (compact Hausdorff) where $U$ does reflect isomorphisms, you have a monadic adjunction! Though not with the discrete space functor, of course.
Apr
21
comment Question about limit of cosimplicial diagram associated with a sheaf
@arrow I assume that $X$ and $Y$ are strictly limits; in sheaf terms, that the sections over $A$ and $B$ are to be exactly equal when restricted to an intersection. A stack only asks for isomorphisms between these restrictions, so $X$ and $Y$ would no longer be strict limits, rather pseudolimits or homotopy limits, depending on the framework.
Apr
21
answered Real singular (co)homology of projective plane/Klein bottle without Mayer-Vietoris/Van-Kampen
Apr
20
revised Question about limit of cosimplicial diagram associated with a sheaf
added 130 characters in body
Apr
20
answered Question about limit of cosimplicial diagram associated with a sheaf