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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-theory cohesive-homotopy-type-theory cohomology 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 finite foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry goodwillie-calculus graph graphs gravity 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 internal-categories k-theory kan lie lie-theory limit limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monoidal monoidal-category-theory morphism motives motivic-cohomology newpage 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 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 topicleptoquark
- Category Latest Changes
- Started by Urs
- Comments 19
- Last comment by Urs
- Last Active 42 minutes ago

- Discussion Type
- discussion topicStein manifold
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active 1 hour ago

have added a tad more content to

*Stein manifold*and cross-linked a bit more

- Discussion Type
- discussion topicquantum information
- Category Latest Changes
- Started by Urs
- Comments 14
- Last comment by Richard Williamson
- Last Active 1 hour ago

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 topicGUT
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active 4 hours ago

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

- Discussion Type
- discussion topicintensional type theory
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 12 hours ago

- Discussion Type
- discussion topictype-theoretic model category
- Category Latest Changes
- Started by Urs
- Comments 18
- Last comment by Mike Shulman
- Last Active 16 hours ago

added to the references-section of the stub

*type-theoretic model category*pointers to André Joyal’s slides on “typoses” (he is currently speaking about that again at CRM in Barcelona).(maybe that entry should be renamed to “categorical semantics for homotopy type theory” or the like, but I won’t further play with it for the time being).

I am also pointing to Mike’s article and to his course notes. I will maybe ask André later, but I am a bit confused about (was already in Halifax) how he presents his typoses, without mentioning of at least very similar categorical semantics that has been discussed before. Maybe I am missing some sociological subtleties here.

- Discussion Type
- discussion topictransferred model structure
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Richard Williamson
- Last Active 22 hours ago

added to transferred model structure a simple remark in a subsection Enrichement on conditions that allow to transfer also an enriched model structure.

(The example I am thinking of is transferring the sSet-enriched model structure on cosimplicial rings to one on cosimplicial smooth algebras. But I won’t type that into the entry for the moment…)

- Discussion Type
- discussion topicmonadic adjunction
- Category Latest Changes
- Started by Mike Shulman
- Comments 7
- Last comment by Mike Shulman
- Last Active 23 hours ago

- Discussion Type
- discussion topictype-theoretic model structure
- Category Latest Changes
- Started by Ulrik
- Comments 3
- Last comment by Ulrik
- Last Active 1 day ago

Initial stub to record some references. Wanted by type theoretic model category

- Discussion Type
- discussion topic(infinity,1)-topos
- Category Latest Changes
- Started by spitters
- Comments 1
- Last comment by spitters
- Last Active 1 day ago

- Discussion Type
- discussion topicFilippo Bonchi
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active 1 day ago

- Discussion Type
- discussion topicFunctorial Semantics of Algebraic Theories
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active 1 day ago

I added the reference

- Filippo Bonchi, Dusko Pavlovic, Pawel Sobocinski,
*Functorial Semantics for Relational Theories*, (arXiv:1711.08699)

- Filippo Bonchi, Dusko Pavlovic, Pawel Sobocinski,

- Discussion Type
- discussion topicholographic entanglement entropy
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active 1 day ago

created a stub for

*holographic entanglement entropy*in reaction to this MO question.

- Discussion Type
- discussion topicflavour anomaly
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active 1 day ago

- Discussion Type
- discussion topicanomalous magnetic moment
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active 1 day ago

there is an old article (Berends-Gastman 75) that computes the 1-loop corrections due to perturbative quantum gravity to the anomalous magnetic moment of the electron and the muon. The result turns out to be independent of the choice of (“re”-)normalization (hence what they call “finite”).

I have added a remark on this in the $(g-2)$-entry here and also at

*quantum gravity*here.

- Discussion Type
- discussion topicaccessible model category
- Category Latest Changes
- Started by Mike Shulman
- Comments 2
- Last comment by Mike Shulman
- Last Active 1 day ago

- Discussion Type
- discussion topicLean
- Category Latest Changes
- Started by Urs
- Comments 47
- Last comment by Guest
- Last Active 1 day ago

added references to

*Lean*

- Discussion Type
- discussion topictau-additive measure
- Category Latest Changes
- Started by PaoloPerrone
- Comments 3
- Last comment by PaoloPerrone
- Last Active 1 day ago

- Discussion Type
- discussion topicFred Jegerlehner
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 2 days ago

brief

`category:people`

-entry for hyperlinking references at*Higgs inflation*and*anomalous magnetic moment*

- Discussion Type
- discussion topiccosmic inflation
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Urs
- Last Active 2 days ago

stub for

*cosmic inflation*(for the moment just to record some references)

- Discussion Type
- discussion topicbiproduct
- Category Latest Changes
- Started by Colin Tan
- Comments 1
- Last comment by Colin Tan
- Last Active 2 days ago

- Discussion Type
- discussion topicstring phenomenology
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active 2 days ago

I ended up collecting some references at

*string phenomenology*and accompanying them with a bit of text

- Discussion Type
- discussion topicgeneral relativity
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active 2 days ago

I wanted to be able to use the link without it appearing in grey, so I created a stub for general relativity.

- Discussion Type
- discussion topicPoisson-Lie T-duality
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active 2 days ago

started a bare minimum at

*Poisson-Lie T-duality*, for the moment just so as to have a place to record the two original references

- Discussion Type
- discussion topicvaluation (measure theory)
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Alizter
- Last Active 2 days ago

- Discussion Type
- discussion topicsemi-left-exact left Bousfield localization
- Category Latest Changes
- Started by Mike Shulman
- Comments 1
- Last comment by Mike Shulman
- Last Active 2 days ago

- Discussion Type
- discussion topicsemi-left-exact reflection
- Category Latest Changes
- Started by Mike Shulman
- Comments 5
- Last comment by Mike Shulman
- Last Active 2 days ago

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

- Discussion Type
- discussion topictribe
- Category Latest Changes
- Started by Mike Shulman
- Comments 1
- Last comment by Mike Shulman
- Last Active 2 days ago

- Discussion Type
- discussion topicproper model category
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Richard Williamson
- Last Active 2 days ago

I expanded proper model category a bit.

In particular I added statement and (simple) proof that in a left proper model category pushouts along cofibrations out of cofibrants are homotopy pushouts. This is at Proper model category -- properties

On page 9 here Clark Barwick supposedly proves the stronger statement that pushouts along all cofibrations in a left proper model category are homotopy pushouts, but for the time being I am failing to follow his proof.

(??)

- Discussion Type
- discussion topictangent (oo,1)-category
- Category Latest Changes
- Started by Urs
- Comments 21
- Last comment by David_Corfield
- Last Active 2 days ago

I rewrote the few sentences at tangent (infinity,1)-category in an attempt to make it run more smoothly.

In any case, there is not much there yet...