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2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry bundle bundles calculus categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration finite foundations functional-analysis functor galois-theory 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 homological homological-algebra homology homotopy homotopy-theory homotopy-type-theory index-theory infinity integration integration-theory itex k-theory lie-theory limits linear linear-algebra locale localization logic mathematics measure measure-theory modal modal-logic model model-category-theory monads monoidal monoidal-category-theory morphism motives motivic-cohomology 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 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 topicquotient type
- Category Latest Changes
- Started by Urs
- Comments 17
- Last comment by nLab edit announcer
- Last Active May 18th 2020

I notice that there seemed to be no-where a really explicit semantics explanation of the claim that “univalence implies the existence of quotient types”. I checked with Peter Lumsdaine, and he kindly provided some text which, up to some minor reformatting, I have put into quotient type – Properties – from univalence.

- Discussion Type
- discussion topicHans-Peter Dürr
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active May 18th 2020

for hyperlinking references at

*quantum hadrodynamics*

- Discussion Type
- discussion topicquantum hadrodynamics -- references
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active May 18th 2020

a bare list of references, to be

`!include`

-ed into the References-section of relevant entries (notably at*quantum hadrodynamics*, of course, but also at*hadron*,*nucleon*etc.)

- Discussion Type
- discussion topicω-meson
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active May 17th 2020

- Discussion Type
- discussion topicBeck module
- Category Latest Changes
- Started by Zhen Lin
- Comments 6
- Last comment by n.mertes
- Last Active May 17th 2020

Created Beck module, mentioned it (once) on the tangent category page.

- Discussion Type
- discussion topicFrames and Locales
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 6
- Last comment by Urs
- Last Active May 17th 2020

- Discussion Type
- discussion topicpartition of unity
- Category Latest Changes
- Started by DavidRoberts
- Comments 9
- Last comment by arsmath
- Last Active May 17th 2020

Cleaned up partition of unity and fine sheaf a bit, so I could link to them from this MO answer to the question ’Why are there so many smooth functions?’.

- Discussion Type
- discussion topichomotopy product
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 3
- Last comment by Hurkyl
- Last Active May 16th 2020

- Discussion Type
- discussion topicfully normal topological space
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 2
- Last comment by DavidRoberts
- Last Active May 16th 2020

- Discussion Type
- discussion topicparacompact topological space
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Dmitri Pavlov
- Last Active May 16th 2020

Added to

*paracompact topological space*in the*Properties*-section the statement that every bounded hypercover over a paracompact space is refined by the Čech nerve of a plain open cover… by appealing to a lemma in HTT. (Thanks to Danny Stevenson for pointing this out.)

- Discussion Type
- discussion topicquantum hadrodynamics
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active May 16th 2020

have added pointer to

- A.Yu. Korchin, D. Van Neck, M. Waroquier,
*Electromagnetic interaction in chiral quantum hadrodynamics and decay of vector and axial-vector mesons*, Phys.Rev. C67 (2003) 015207 (arXiv:nucl-th/0302042)

- A.Yu. Korchin, D. Van Neck, M. Waroquier,

- Discussion Type
- discussion topiccodomain fibration
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by T
- Last Active May 16th 2020

have added to

*codomain fibration*a brief paragraph on the $(\infty,1)$-version here and that it’s a coCartesian fibration.

- Discussion Type
- discussion topicreal-valued-measurable cardinal
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 1
- Last comment by Dmitri Pavlov
- Last Active May 15th 2020

- Discussion Type
- discussion topichomotopy coproduct
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 2
- Last comment by Dmitri Pavlov
- Last Active May 15th 2020

- Discussion Type
- discussion topicstabilization
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Dmitri Pavlov
- Last Active May 15th 2020

started entry on stabilization (in the sense of sending an (oo,1)-category to its free stable (infinity,1)-category)

I want to eventually state more properties of the effect of stabilization on objects here.

- Discussion Type
- discussion topictensor product of vector spaces
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Dmitri Pavlov
- Last Active May 15th 2020

- Discussion Type
- discussion topicXYZ particle
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active May 15th 2020

- Discussion Type
- discussion topictopological order
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 15th 2020

added pointer to today’s

- Amit Jamadagni, Hendrik Weimer,
*An Operational Definition of Topological Order*(arXiv:2005.06501)

- Amit Jamadagni, Hendrik Weimer,

- Discussion Type
- discussion topicShai Chester
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 15th 2020

brief

`category:people`

-entry for hyperlinking references at*conformal bootstrap*

- Discussion Type
- discussion topicconformal bootstrap
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active May 15th 2020

added pointers:

For superconformal field theory, such as D=4 N=1 SYM, D=4 N=2 SYM, D=4 N=4 SYM, D=6 N=(1,0) SCFT, D=6 N=(2,0) SCFT:

Christopher Beem, Madalena Lemos, Pedro Liendo, Leonardo Rastelli, Balt C. van Rees,

*The $N=2$ superconformal bootstrap*(arXiv:1412.7541)Christopher Beem, Madalena Lemos, Leonardo Rastelli, Balt C. van Rees,

*The $(2,0)$ superconformal bootstrap*(arXiv:1507.05637)Christopher Beem, Leonardo Rastelli, Balt C. van Rees,

*More $N=4$ superconformal bootstrap*(arXiv:1612.02363)

- Discussion Type
- discussion topiccartesian bicategories
- Category Latest Changes
- Started by Todd_Trimble
- Comments 17
- Last comment by Mike Shulman
- Last Active May 14th 2020

After a shamefully long time, I am working some more on cartesian bicategory; I have added some material on the locally cartesian structure, on the essential uniqueness of a cartesian structure on a bicategory, and a beginning of a section on the “Frobenius conditions”.

I also inserted a little promissory note acknowledging that it really would be better to deal with framed cartesian bicategories, by tweaking the definition a little. It would require a certain amount of rewriting (which makes me believe that I had better do it sooner than later).

A few days ago here at the nForum, I outlined a context where these Frobenius conditions imply “Frobenius reciprocity” (in response to a query of David Corfield). I want to see whether I can write out or at least sketch a proof in the context of a cartesian bicategory satisfying the Frobenius conditions, and see what else might be said on the relationship between the two Frobenii.

- Discussion Type
- discussion topicnumerable open cover
- Category Latest Changes
- Started by arsmath
- Comments 16
- Last comment by Guest
- Last Active May 14th 2020

- Discussion Type
- discussion topicstandard model of particle physics
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Urs
- Last Active May 14th 2020

**Edit to**: standard model of particle physics by Urs Schreiber at 2018-04-01 01:15:37 UTC.**Author comments**:added textbook reference

- Discussion Type
- discussion topicM2-brane
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active May 14th 2020

added a bunch of references to

*M2-brane*

- Discussion Type
- discussion topictheory of flat functors
- Category Latest Changes
- Started by Thomas Holder
- Comments 4
- Last comment by Todd_Trimble
- Last Active May 13th 2020

- Discussion Type
- discussion topictphyahoo
- Category Latest Changes
- Started by tphyahoo
- Comments 1
- Last comment by tphyahoo
- Last Active May 13th 2020

- Discussion Type
- discussion topicSage
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active May 13th 2020

- Discussion Type
- discussion topicDavid Berman
- Category Latest Changes
- Started by Luigi
- Comments 1
- Last comment by Luigi
- Last Active May 13th 2020

- Discussion Type
- discussion topicRozansky-Witten theory
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active May 13th 2020

- Discussion Type
- discussion topicphi-meson
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active May 12th 2020