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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 complex-geometry computable-mathematics computer-science constructive constructive-mathematics cosmology definitions deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry differential-topology digraphs duality elliptic-cohomology enriched fibration finite foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry goodwillie-calculus 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 manifolds mathematics measure-theory modal-logic model model-category-theory monads 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 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-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 topicAdS-CFT
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicspheres -- contents
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topic5-sphere
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicdilatation operator
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicHans Bethe
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

brief

`category:people`

-entry for hyperlinking references at*spin chain*

- Discussion Type
- discussion topicspin chain
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicMatthias Staudacher
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicNiklas Beisert
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicD=4 N=4 super Yang-Mills theory
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active 6 days ago

added to

*N=4 D=4 super Yang-Mills theory*a section*Properties – Closed expressions for physical observables*with a brief mentioning of integrability of the dilatation operator, MHV amplitudes and planar limit scattering amplitudes.

- Discussion Type
- discussion topicKonstantin Zarembo
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicpre-net
- Category Latest Changes
- Started by nLab edit announcer
- Comments 4
- Last comment by Todd_Trimble
- Last Active 6 days ago

- Discussion Type
- discussion topicDp-D(p+2)-brane bound state
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicsu(2)
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicfuzzy sphere
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicGiovanni Caviglia
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Tim_Porter
- Last Active 6 days ago

brief

`category:people`

-entry for hyperlinking references at*model structure on operads*, and*Feynman category*

- Discussion Type
- discussion topicPrithvi Narayan
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

brief

`category:people`

-entry for hyperlinking references at*single trace operator*,*SYK model*and*weight systems on chord diagrams in physics*

- Discussion Type
- discussion topicsquare matrix
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicsubspace topology
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by mdavis
- Last Active 6 days ago

added statement of the universal property (here), first in classical form, then using the sharp modality, and added remark that this should be the categorical semantics of Mike’s remark 3.14 in arXiv:1509.07584

(also replaced the Definition-paragraph with a slightly beautified version)

- Discussion Type
- discussion topicPetri net
- Category Latest Changes
- Started by Tim_Porter
- Comments 9
- Last comment by nLab edit announcer
- Last Active 6 days ago

I have created a stub for this at Petri net. I hope to develop the links with higher dimensional automata and also with linear logic.

- Discussion Type
- discussion topicThomas Mertens
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

brief

`category:people`

-entry for hyperlinking references at*Sachdev-Ye-Kitaev model*,*Jackiw-Teitelboim gravity*but also at*weight system*and*chord diagram*

- Discussion Type
- discussion topicHenri Verschelde
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

brief

`category:people`

-entry for hyperlinking references at*Sachdev-Ye-Kitaev model*,*Jackiw-Teitelboim gravity*but also at*weight system*and*chord diagram*

- Discussion Type
- discussion topicAndreas Blommaert
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

brief

`category:people`

-entry for hyperlinking references at*Sachdev-Ye-Kitaev model*,*Jackiw-Teitelboim gravity*but also at*weight system*and*chord diagram*

- Discussion Type
- discussion topicSachdev-Ye-Kitaev model
- Category Latest Changes
- Started by Urs
- Comments 13
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicLie algebra representation
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

added the string diagram incarnation of the Lie action property (here), copied over from

*STU relation*.Will add this also to

*Jacobi identity*

- Discussion Type
- discussion topicSTU relation
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topic4-sphere
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active 7 days ago

added this to the list of references:

Speculative remarks on the possible role of maps from spacetime to the 4-sphere in some kind of quantum gravity via spectral geometry are in

- Ali Chamseddine, Alain Connes, Viatcheslav Mukhanov, section 4 of
*Geometry and the Quantum: Basics*, JHEP 12 (2014) 098 (arXiv:1411.0977)

reviewed in

Alain Connes, section 4 of

*Geometry and the Quantum*, Foundations of Mathematics and Physics One Century After Hilbert. Springer, Cham, 2018. 159-196 (arXiv:1703.02470)Alain Connes, from 58:00 to 1:25:00 in

*Why Four Dimensions and the Standard Model Coupled to Gravity - A Tentative Explanation From the New Geometric Paradigm of NCG*, talk at IHES, 2017 (video recording)

- Ali Chamseddine, Alain Connes, Viatcheslav Mukhanov, section 4 of

- Discussion Type
- discussion topicalgebraic topology
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Mike Shulman
- Last Active 7 days ago

I have tried to give

*algebraic topology*a better Idea-section.

- Discussion Type
- discussion topiccategory with class structure
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 6
- Last comment by Mike Shulman
- Last Active 7 days ago

- Discussion Type
- discussion topicexponential object
- Category Latest Changes
- Started by Urs
- Comments 12
- Last comment by Mike Shulman
- Last Active 7 days ago

I had started an entry “exponentiation” but then thought better of it and instead expanded the existing exponential object: added an examples-section specifically for $Set$ and made some remarks on exponentiation of numbers.

- Discussion Type
- discussion topicAndré Joyal
- Category Latest Changes
- Started by Tim_Porter
- Comments 5
- Last comment by Tim_Porter
- Last Active 7 days ago