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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 beauty bundles calculus categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex-geometry computable-mathematics computer-science connection constructive constructive-mathematics cosmology definitions deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry differential-topology digraphs duality education elliptic-cohomology enriched fibration 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-theory limits linear linear-algebra locale localization logic manifolds mathematics measure-theory modal-logic model model-category-theory monad monoidal monoidal-category-theory morphism motives motivic-cohomology multicategories 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 stack 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 topiclists of journals
- Category Latest Changes
- Started by Mike Shulman
- Comments 20
- Last comment by Dmitri Pavlov
- Last Active Jul 29th 2019

- Discussion Type
- discussion topicmatroid
- Category Latest Changes
- Started by Todd_Trimble
- Comments 10
- Last comment by nLab edit announcer
- Last Active Jul 29th 2019

I have been adding some material to matroid. I haven’t gotten around to defining oriented matroid yet (and of course there’s much besides to add).

- Discussion Type
- discussion topicBohr topos
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Jul 29th 2019

expanded the section

*Idea – In brief*at*Bohr topos*just a little bit, in order to amplify the relation to Jordan algebras better (which previously was a bit hidden in entry).

- Discussion Type
- discussion topicKochen-Specker theorem
- Category Latest Changes
- Started by Ian_Durham
- Comments 17
- Last comment by Urs
- Last Active Jul 29th 2019

Since no one objected to my offer, I started a stub for the Kochen-Specker theorem and will continue working on it a bit later.

- Discussion Type
- discussion topicarity space
- Category Latest Changes
- Started by Mike Shulman
- Comments 9
- Last comment by Sam Staton
- Last Active Jul 29th 2019

- Discussion Type
- discussion topicFrames and Locales
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 1
- Last comment by Dmitri Pavlov
- Last Active Jul 28th 2019

- Discussion Type
- discussion topicMehrnoosh Sadrzadeh
- Category Latest Changes
- Started by Tim_Porter
- Comments 1
- Last comment by Tim_Porter
- Last Active Jul 28th 2019

- Discussion Type
- discussion topicdouble category
- Category Latest Changes
- Started by John Baez
- Comments 7
- Last comment by nLab edit announcer
- Last Active Jul 28th 2019

- I added more info on pseudo double categories and double bicategories to double category. I also simplified the picture of a square, which had been bristling with scary unnecessary detail. There's a slight blemish in the left vertical arrow, which I can't see how to fix.

- Discussion Type
- discussion topicexceptional generalized geometry
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Jul 28th 2019

added to

*exceptional generalized geometry*two examples of reductions of stucture groups that encode higher supersymmetry in 11d sugra.

- Discussion Type
- discussion topicribbon category
- Category Latest Changes
- Started by nLab edit announcer
- Comments 4
- Last comment by John Baez
- Last Active Jul 28th 2019

- Discussion Type
- discussion topicBoolean locale
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 8
- Last comment by Mike Shulman
- Last Active Jul 27th 2019

- Discussion Type
- discussion topicE11
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Jul 27th 2019

have added a minimum on the level decompositon of the first fundamental rep of $E_{11}$ here.

- Discussion Type
- discussion topicM2-brane
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Jul 27th 2019

added a bunch of references to

*M2-brane*

- Discussion Type
- discussion topicsuperstring
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Jul 27th 2019

for completeness, I have splitt off superstring from string

- Discussion Type
- discussion topicinfinity-group
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active Jul 27th 2019

- Discussion Type
- discussion topicstandard model of cosmology
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active Jul 27th 2019

added this, under References – Review:

- V.F. Mukhanov,
*Quantum Universe*, Phys.Usp. 59 (2016) no.10, 1021-1027 (spire:1507528, doi:10.3367/UFNe.2016.07.037857)

In March 2013, following an accurate processing of available measurement data, the Planck Scientific Collaboration published the highest-resolution photograph ever of the early Universe when it was only a few hundred thousand years old. The photograph showed galactic seeds in sufficient detail to test some nontrivial theoretical predictions made more than thirty years ago. Most amazing was that all predictions were confirmed to be remarkably accurate. With no exaggeration, we may consider it established experimentally that quantum physics, which is normally assumed to be relevant on the atomic and subatomic scale, also works on the scale of the entire Universe, determining its structure with all its galaxies, stars, and planets.

- V.F. Mukhanov,

- Discussion Type
- discussion topicself-dual higher gauge theory
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Jul 27th 2019

started self-dual higher gauge theory. Just minimal idea and list of references so far.

- Discussion Type
- discussion topicDmitrij Volkov
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 27th 2019

added a bunch of further links, and made

*Dmitry Volkov*a redirect

- Discussion Type
- discussion topicpretopos
- Category Latest Changes
- Started by Mike Shulman
- Comments 7
- Last comment by David_Corfield
- Last Active Jul 26th 2019

I have incorporated Jonas’ comment into the text at pretopos, changing the definition to “a category that is both exact and extensive”, as this is sufficient to imply that it is both regular and coherent.

- Discussion Type
- discussion topicSimon Cho
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active Jul 26th 2019

- Discussion Type
- discussion topicclassical r-matrix
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Jul 25th 2019

- Discussion Type
- discussion topicquantum Yang-Baxter matrix
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active Jul 25th 2019

- Discussion Type
- discussion topicreflection equation algebra
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active Jul 25th 2019

- Discussion Type
- discussion topicSome page
- Category Latest Changes
- Started by Tim_Porter
- Comments 3
- Last comment by Richard Williamson
- Last Active Jul 25th 2019

- Discussion Type
- discussion topicW-type
- Category Latest Changes
- Started by Mike Shulman
- Comments 8
- Last comment by spitters
- Last Active Jul 25th 2019

Created W-type.

- Discussion Type
- discussion topicregular space
- Category Latest Changes
- Started by Mike Shulman
- Comments 8
- Last comment by Mike Shulman
- Last Active Jul 25th 2019

I added to regular space a remark that any regular space admits a naturally defined apartness relation.

- Discussion Type
- discussion topictotality space
- Category Latest Changes
- Started by Mike Shulman
- Comments 2
- Last comment by Mike Shulman
- Last Active Jul 25th 2019

Stub to satisfy a link from arity space.

- Discussion Type
- discussion topictopological locale
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 1
- Last comment by Dmitri Pavlov
- Last Active Jul 25th 2019

- Discussion Type
- discussion topictheta angle
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 25th 2019

added mentioning of the $\theta$-angle in AdS/QCD models being the graviphoton in the higher WZW-term of the D4-brane, with pointer to today’s

- Si-wen Li, around (3.1) of
*The theta-dependent Yang-Mills theory at finite temperature in a holographic description*(arXiv:1907.10277)

and cross-linked with other relevant entries

- Si-wen Li, around (3.1) of

- Discussion Type
- discussion topictopology
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 25th 2019

added pointer to

- Michael Müger,
*Topology for the working mathematician*, Nijmegen 2018 (pdf)

- Michael Müger,