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2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry beauty bundles calculus categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex-geometry computable-mathematics computer-science constructive constructive-mathematics cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry graph graphs gravity group group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory history homological homological-algebra homology homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie lie-theory limits linear linear-algebra locale localization logic mathematics measure measure-theory modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology multicategories nlab noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pages pasting philosophy physics planar 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 string string-theory subobject superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

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- Discussion Type
- discussion topicinfinity-groupoid
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 1
- Last comment by Dmitri Pavlov
- Last Active 33 minutes ago

- Discussion Type
- discussion topicTupac Shakur
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 41 minutes ago

- Discussion Type
- discussion topicinquiry driven system
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 8 hours ago

- Discussion Type
- discussion topicω-meson
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active 9 hours ago

- Discussion Type
- discussion topicsmoothing kernels
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 11 hours ago

- Discussion Type
- discussion topicskyrmion
- Category Latest Changes
- Started by Urs
- Comments 19
- Last comment by Urs
- Last Active 15 hours ago

- Discussion Type
- discussion topicquark bag model
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active 16 hours ago

- Discussion Type
- discussion topicunit of an adjunction
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by varkor
- Last Active 16 hours ago

The entry

*unit of an adjunction*had a big chunk of mixed itex+svg code at the beginning to display an adjunction. On my machine though the output of that code was ill typeset. So I have removed the code and replaced it by plain iTex encoding of an adjunction.(Just in case anyone deeply cares about the svg that was there. It’s still in the history. If it is preferred by anyone, it needs to be fixed first.)

- Discussion Type
- discussion topichidden local symmetry
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active 16 hours ago

- Discussion Type
- discussion topicMasako Bando
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 16 hours ago

brief

`category:people`

-entry for hyperlinking references at*hidden local symmetry*

- Discussion Type
- discussion topicfundamental scales -- contents
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 20 hours ago

- Discussion Type
- discussion topicSchwinger limit
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 20 hours ago

splitting this off from

*Schwinger effect*, to go with a list of entries on fundamental scales

- Discussion Type
- discussion topicrest energy
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 21 hours ago

- Discussion Type
- discussion topicchiral perturbation theory
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active 21 hours ago

- Discussion Type
- discussion topicenergy condition
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 22 hours ago

added pointer to today’s

- Felipe Rosso,
*Global aspects of conformal symmetry and the ANEC in dS and AdS*(arXiv:1912.08897)

- Felipe Rosso,

- Discussion Type
- discussion topicleptoquark
- Category Latest Changes
- Started by Urs
- Comments 34
- Last comment by Urs
- Last Active 22 hours ago

- Discussion Type
- discussion topicDirac-Born-Infeld action
- Category Latest Changes
- Started by Urs
- Comments 21
- Last comment by Urs
- Last Active 1 day ago

added pointer to Schwarz 01

- Discussion Type
- discussion topicmoment map
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active 1 day ago

I have expanded and edited

*moment map*.

- Discussion Type
- discussion topicSchwinger effect
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active 1 day ago

- Discussion Type
- discussion topicmonoidal category
- Category Latest Changes
- Started by Urs
- Comments 55
- Last comment by Mike Shulman
- Last Active 2 days ago

Todd,

when you see this here and have a minute, would you mind having a look at

*monoidal category*to see if you can remove the query-box discussion there and maybe replace it by some crisp statement?Thanks!

- Discussion Type
- discussion topiccohesive topos
- Category Latest Changes
- Started by Urs
- Comments 89
- Last comment by nLab edit announcer
- Last Active 2 days ago

created cohesive topos.

wrote an Idea-section that is meant to explain why the concept is very natural, trying to provide some of the chat that one cannot find in the terse (but beautiful in its own way) article by Lawvere

spelled out the definition in some detail, here, too, trying to fill in things that Lawvere is glossing over, making it all very explicit;

started an Examples-section:

copied over the discussion that $Sh(CartSp)$ is a connected topos. checking the remaining axioms for cohesive topos are easy, but i have not typed that yet

included a little discussion of how diffeological spaces fit in, following our conversation in another thread

started an analogous section for $\infty Sh(CartSp)$, but just a stub so far

but added in a section that goes rgrough the various items in Lawvere’s definition and discusses their meaning in a cohesive oo-topos

- Discussion Type
- discussion topicHarder-Narasimhan theorem
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 2 days ago

added pointer to today’s

- Jonathan Pottharst,
*Harder-Narasimhan theory*(arXiv:2003.11950)

- Jonathan Pottharst,

- Discussion Type
- discussion topicreflexive coequalizer
- Category Latest Changes
- Started by Mike Shulman
- Comments 7
- Last comment by nLab edit announcer
- Last Active 2 days ago

Created reflexive coequalizer.

- Discussion Type
- discussion topictriangulated categories of sheaves
- Category Latest Changes
- Started by adeelkh
- Comments 8
- Last comment by timhosgood
- Last Active 3 days ago

I created the page

with some discussion and references on the various triangulated categories associated to a scheme (e.g. bounded derived category of coherent sheaves, triangulated category of perfect complexes).

- Discussion Type
- discussion topiclocalic topos
- Category Latest Changes
- Started by mattecapu
- Comments 1
- Last comment by mattecapu
- Last Active 3 days ago

- Discussion Type
- discussion topicJiří Chýla
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 4 days ago

brief

`category:people`

-entry for hyperlinking references at*quark*and*quantum chromodynamics*

- Discussion Type
- discussion topicHans Euler
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago

- Discussion Type
- discussion topicpolycategory
- Category Latest Changes
- Started by varkor
- Comments 5
- Last comment by varkor
- Last Active 4 days ago

- Discussion Type
- discussion topictwo-out-of-six property
- Category Latest Changes
- Started by Mike Shulman
- Comments 2
- Last comment by nLab edit announcer
- Last Active 4 days ago

I noticed that some Anonymous Coward had created a very stubby stub at two-out-of-six property, and used it as a place to put proofs of two theorems about when the 2-out-of-6 property is equivalent to saturation of the class of weak equivalences.

- Discussion Type
- discussion topicMassimo Porrati
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago