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2-categories 2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry bundles calculus categories category category-theory chern-weil-theory cohesion cohesive-homotopy-theory cohesive-homotopy-type-theory cohomology colimits combinatorics comma complex-geometry computable-mathematics computer-science constructive cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry differential-topology digraphs duality education elliptic-cohomology enriched fibration finite foundations functional-analysis functor galois-theory gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck 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 infinity integration integration-theory k-theory lie lie-theory limit limits linear linear-algebra locale localization logic mathematics measure-theory modal-logic model model-category-theory monoidal monoidal-category-theory morphism motives motivic-cohomology multicategories nonassociative noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory 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 type type-theory universal variational-calculus

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- Discussion Type
- discussion topicRandall-Sundrum model
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Jan 22nd 2019

- Discussion Type
- discussion topicAndreas Crivellin
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jan 22nd 2019

brief

`category:people`

-entry for hyperlinking references at*flavour anomaly*,*leptoquark*and*electric dipole moment*

- Discussion Type
- discussion topicquiver gauge theory
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Jan 22nd 2019

started something at

*quiver gauge theory*; some very basic sentences on the Idea of it all, and some bare minimum of references.This is a vast subject, and clearly that entry deserves to be expanded much further.

In the course of creating this I needed to create brief entries

*B-brane*and*exceptional collection*.

- Discussion Type
- discussion topicMcKay quiver
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Jan 22nd 2019

- Discussion Type
- discussion topicKaluza-Klein monopole
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Jan 22nd 2019

I have tried to clarify a bit more at

*Kaluza-Klein monopole*, and at*D6-brane*

- Discussion Type
- discussion topicgeometric morphism
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by varkor
- Last Active Jan 22nd 2019

at geometric morphism in the new section Structure preserved by geometric morphisms I wanted to expand on Johnstone’s remark B2.2.7 on how geometric morphisms preserve the characteristic well-powerdness of toposes as indexed categories over themselves. I have started at indexed category a section on well-poweredness for that purpose, but I have to leave things in very incomplete form for the moment.

- Discussion Type
- discussion topicpentagon identity
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Richard Williamson
- Last Active Jan 22nd 2019

There was no references here. Added pointer to

- André Joyal,Ross Street, p. 10 of
*Braided tensor categories*, Adv. Math. 1993 (pdf)

- André Joyal,Ross Street, p. 10 of

- Discussion Type
- discussion topicsemi-left-exact reflection
- Category Latest Changes
- Started by Mike Shulman
- Comments 18
- Last comment by Richard Williamson
- Last Active Jan 21st 2019

Split page from reflective factorization system, with some additional characterizations.

- Discussion Type
- discussion topicelectric dipole moment
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jan 21st 2019

- Discussion Type
- discussion topicpreset
- Category Latest Changes
- Started by atmacen
- Comments 4
- Last comment by atmacen
- Last Active Jan 21st 2019

The example of $Q$ as a Bishop set on the preset $Z \times Z$ is wrong. You need to rule out zero denominators. The definition currently on the page is not a Bishop set at all, because $0/0$ makes the relation intransitive.

I’m not sure how it should be changed to illustrate the point that the same preset can get distinct sets. Maybe a different example entirely?

- Discussion Type
- discussion topicAdS-QCD correspondence
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Jan 21st 2019

- Discussion Type
- discussion topictype 0 string theory
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jan 21st 2019

some minimum, to satisfy new links from

*AdS-QCD correspondence*

- Discussion Type
- discussion topicsemi-left-exact left Bousfield localization
- Category Latest Changes
- Started by Mike Shulman
- Comments 2
- Last comment by Mike Shulman
- Last Active Jan 20th 2019

- Discussion Type
- discussion topicinternal category in homotopy type theory
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Guest
- Last Active Jan 20th 2019

I finally created an entry

*internal category in homotopy type theory*.There is old discussion of this topic which I had once written at

*category object in an (infinity,1)-category*in the sub-section*HoTT formulation*, but it’s probably good to give this a stand-alone entry, for ease of linking (such as from*equivalence of categories*now).

- Discussion Type
- discussion topicinformation geometry
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by David_Corfield
- Last Active Jan 20th 2019

started information geometry to go with the blog discussion

- Discussion Type
- discussion topicgeometric Langlands correspondence
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Jan 20th 2019

a beginning at geometric Langlands correspondence

- Discussion Type
- discussion topicFivebrane structure
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jan 20th 2019

added full publication data for

- Boris Botvinnik, Mohammed Labbi,
*Highly connected manifolds of positive $p$-curvature*, Transactions of the AMS, Trans. Amer. Math. Soc. 366 (2014), 3405-3424 (arXiv:1201.1849, doi:10.1090/S0002-9947-2014-05939-4)

- Boris Botvinnik, Mohammed Labbi,

- Discussion Type
- discussion topictype-theoretic definition of category
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jan 20th 2019

cross-linked this old entry with

*internal category in homotopy type theory*

- Discussion Type
- discussion topicrepresentation theory
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Jan 19th 2019

gave

*representation theory*a little Idea-section, then added some words on its incarnation as homotopy type theory in context/in the slice over $\mathbf{B}G$ and added the following*homotopy type representation theory – table*, which I am also including in other relevant entries:homotopy type theory representation theory pointed connected context $\mathbf{B}G$ ∞-group $G$ dependent type ∞-action/∞-representation dependent sum along $\mathbf{B}G \to \ast$ coinvariants/homotopy quotient context extension along $\mathbf{B}G \to \ast$ trivial representation dependent product along $\mathbf{B}G \to \ast$ homotopy invariants/∞-group cohomology dependent sum along $\mathbf{B}G \to \mathbf{B}H$ induced representation context extension along $\mathbf{B}G \to \mathbf{B}H$ dependent product along $\mathbf{B}G \to \mathbf{B}H$ coinduced representation

- Discussion Type
- discussion topicRoberto Trotta
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active Jan 19th 2019

- Discussion Type
- discussion topicBayesian reasoning
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active Jan 19th 2019

- Discussion Type
- discussion topiccentral limit theorem
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Jan 19th 2019

- Discussion Type
- discussion topicalgebraic definition of higher categories
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Tim_Porter
- Last Active Jan 19th 2019

tried to polish algebraic definition of higher categories a little

- Discussion Type
- discussion topicduality in string theory
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Jan 18th 2019

I needed an entry to be able to point to which collects pointers to the various entries on “dualities” in string theory. So I created one:

*duality in string theory*.

- Discussion Type
- discussion topicalgebraic model category
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Mike Shulman
- Last Active Jan 18th 2019

created algebraic model category

- Discussion Type
- discussion topicthreshold correction
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Jan 18th 2019

- Discussion Type
- discussion topicGUT
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Jan 18th 2019

**Edit to**: GUT by Urs Schreiber at 2018-04-01 01:21:13 UTC.**Author comments**:added pointer to textbook account

- Discussion Type
- discussion topicquantum information
- Category Latest Changes
- Started by Urs
- Comments 17
- Last comment by Urs
- Last Active Jan 18th 2019

Aleks Kissinger has contacted me about his aims to start a collection of nLab entries on quantum information from the point of view of the Bob Coecke school.

Being very much delighted about this offer, I created a template entry quantum information for his convenience.

- Discussion Type
- discussion topicAusdehnungslehre
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by DavidRoberts
- Last Active Jan 17th 2019

- Discussion Type
- discussion topicHurewicz model structure on chain complexes
- Category Latest Changes
- Started by Mike Shulman
- Comments 1
- Last comment by Mike Shulman
- Last Active Jan 17th 2019