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2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry book bundles calculus categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology definitions deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration foundation foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck group group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory homological homological-algebra homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie-theory limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology nforum nlab noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pages pasting philosophy physics pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory stack string string-theory superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

1. • CommentRowNumber1.
   • CommentAuthornLab edit announcer
   • CommentTimeDec 3rd 2020
   • PermaLink
   Author: nLab edit announcer
   Format: MarkdownItexadded reference to HTT Shane Kelly <a href="https://ncatlab.org/nlab/revision/diff/effective+epimorphism/24">diff</a>, <a href="https://ncatlab.org/nlab/revision/effective+epimorphism/24">v24</a>, <a href="https://ncatlab.org/nlab/show/effective+epimorphism">current</a>

   added reference to HTT

   Shane Kelly

   diff, v24, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeJun 18th 2021
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to: * [[Alexander Grothendieck]], p. 101 (4 of 21) in: _Techniques de construction et théorèmes d'existence en géométrie algébrique III : préschémas quotients_, Séminaire Bourbaki: années 1960/61, exposés 205-222, Séminaire Bourbaki, no. 6 (1961), Exposé no. 212, ([numdam:SB_1960-1961__6__99_0](http://www.numdam.org/item/?id=SB_1960-1961__6__99_0), [pdf](http://www.numdam.org/item/SB_1960-1961__6__99_0.pdf)) <a href="https://ncatlab.org/nlab/revision/diff/effective+epimorphism/25">diff</a>, <a href="https://ncatlab.org/nlab/revision/effective+epimorphism/25">v25</a>, <a href="https://ncatlab.org/nlab/show/effective+epimorphism">current</a>

   added pointer to:

   • Alexander Grothendieck, p. 101 (4 of 21) in: Techniques de construction et théorèmes d’existence en géométrie algébrique III : préschémas quotients, Séminaire Bourbaki: années 1960/61, exposés 205-222, Séminaire Bourbaki, no. 6 (1961), Exposé no. 212, (numdam:SB_1960-1961__6__99_0, pdf)

   diff, v25, current

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeSep 29th 2021
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to: * [[Francis Borceux]], Def. 2.5.3 in: *[[Handbook of Categorical Algebra]]*, Vol. 2: *Categories and Structures*, Encyclopedia of Mathematics and its Applications **50**, Cambridge University Press (1994) ([doi:10.1017/CBO9780511525865](https://doi.org/10.1017/CBO9780511525865)) <a href="https://ncatlab.org/nlab/revision/diff/effective+epimorphism/27">diff</a>, <a href="https://ncatlab.org/nlab/revision/effective+epimorphism/27">v27</a>, <a href="https://ncatlab.org/nlab/show/effective+epimorphism">current</a>

   added pointer to:

   • Francis Borceux, Def. 2.5.3 in: Handbook of Categorical Algebra, Vol. 2: Categories and Structures, Encyclopedia of Mathematics and its Applications 50, Cambridge University Press (1994) (doi:10.1017/CBO9780511525865)

   diff, v27, current

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeJul 7th 2022
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to * [[Francis Borceux]], Section 3.3.4 of: *[[Handbook of Categorical Algebra]]*. Vol. 3. *Categories of Sheaves*, Encyclopedia of Mathematics and its Applications **50** Cambridge University Press (1994) &lbrack;[doi:10.1017/CBO9780511525872](https://doi.org/10.1017/CBO9780511525872)&rbrack; for the claim that in a topos every epimorphism is effective <a href="https://ncatlab.org/nlab/revision/diff/effective+epimorphism/29">diff</a>, <a href="https://ncatlab.org/nlab/revision/effective+epimorphism/29">v29</a>, <a href="https://ncatlab.org/nlab/show/effective+epimorphism">current</a>

   added pointer to

   • Francis Borceux, Section 3.3.4 of: Handbook of Categorical Algebra. Vol. 3. Categories of Sheaves, Encyclopedia of Mathematics and its Applications 50 Cambridge University Press (1994) [doi:10.1017/CBO9780511525872]

   for the claim that in a topos every epimorphism is effective

   diff, v29, current

5. • CommentRowNumber5.
   • CommentAuthornLab edit announcer
   • CommentTimeSep 12th 2024
   • PermaLink
   Author: nLab edit announcer
   Format: MarkdownItexAdded an example of effective epis that give a good notion of "cover" - open covers! Pseudonium <a href="https://ncatlab.org/nlab/revision/diff/effective+epimorphism/30">diff</a>, <a href="https://ncatlab.org/nlab/revision/effective+epimorphism/30">v30</a>, <a href="https://ncatlab.org/nlab/show/effective+epimorphism">current</a>

   Added an example of effective epis that give a good notion of “cover” - open covers!

   Pseudonium

   diff, v30, current