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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 categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-theory 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 foundation foundations functional-analysis functor galois-theory gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck 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 homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie lie-theory limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad 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 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 sheaves simplicial space spin-geometry stable-homotopy-theory string string-theory 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 topic(infinity,1)-Grothendieck construction
- Category Latest Changes
- Started by Hurkyl
- Comments 7
- Last comment by Urs
- Last Active Jul 7th 2022

- Discussion Type
- discussion topicCabibbo anomaly
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Jul 7th 2022

this has been seen over $4\sigma$ for a while now; time to record some references and to relate to

*flavour anomaly*.Just starting here, from my phone over coffee. Nothing much to see here yet.

- Discussion Type
- discussion topicJulian Sonner
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 7th 2022

- Discussion Type
- discussion topicreal reciprocal function
- Category Latest Changes
- Started by nLab edit announcer
- Comments 4
- Last comment by Urs
- Last Active Jul 7th 2022

- Discussion Type
- discussion topicreciprocal function
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Urs
- Last Active Jul 7th 2022

- Discussion Type
- discussion topicfunctorial field theory
- Category Latest Changes
- Started by Urs
- Comments 12
- Last comment by Guest
- Last Active Jul 6th 2022

I am beginning to give the entry

*FQFT*a comprehensive*Exposition and Introduction*section.So far I have filled some genuine content into the first subsection

*Quantum mechanics in Schrödinger picture*.But I have to quit now. This isn’t even proof-read yet. So don’t look at it unless you feel more in editing-mood than in pure-reading-mood.

- Discussion Type
- discussion topicpasting law for pullbacks
- Category Latest Changes
- Started by Tobias Fritz
- Comments 7
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicKan fibration
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Jul 6th 2022

added the pointers to the combinatorial proofs of the fiberwise detection of acyclicity of Kan fibrations, currently discussed on the AlgTop list, to the nLab here.

- Discussion Type
- discussion topicSimpSet
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topiccategory of presheaves
- Category Latest Changes
- Started by Urs
- Comments 21
- Last comment by Urs
- Last Active Jul 6th 2022

I felt there should be an entry category of presheaves. So I started one.

- Discussion Type
- discussion topichomotopy Kan fibration
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active Jul 6th 2022

giving this its own entry (the concept used to appear in-line at

*geometric realization of simplicial topological spaces*) for ease of hyperlinking. But just the bare definition, for the moment.

- Discussion Type
- discussion topiclax (∞,1)-colimit
- Category Latest Changes
- Started by Hurkyl
- Comments 10
- Last comment by Hurkyl
- Last Active Jul 6th 2022

I added the description of lax (co)limits of Cat-valued functors via (co)ends and ordinary (co)limits. I should probably flesh this out more.

I’ve adopted the convention on twisted arrows at twisted arrow category, which is opposite of that in GNN.

In the case of ordinary 2-category, when the diagram category is a 1-category, is the expression of lax (co)limits via ordinary weighted (co)limits really as simple as taking the weights $C_{\bullet/}$ or $C_{/\bullet}$? I can’t find a reference that spells that out clearly; if there really is such a simple description it should be put on the lax (co)limit page.

- Discussion Type
- discussion topicAlisa Govzmann
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicDamjan Pištalo
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicNorbert Poncin
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicamazing right adjoint
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by mattecapu
- Last Active Jul 6th 2022

created amazing right adjoint

- Discussion Type
- discussion topicgroup actions on spheres
- Category Latest Changes
- Started by Urs
- Comments 27
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicdihedral group
- Category Latest Changes
- Started by Tim_Porter
- Comments 7
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicalgebra
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active Jul 6th 2022

the topic-cluster “algebra” is stiil a little orphaned on the Lab, I find. I added a bit to

but these entries are still a bit pitiful. Maybe somebody feels challenged to turn them into good entries. Especially the latter.

Should we have pages algebra over a Lawvere theory, algebra over a PROP, etc? Some entries look like they want such links (for instance algebra itself).

- Discussion Type
- discussion topicJoseph A. Gallian
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicfundamental theorem of finitely generated abelian groups
- Category Latest Changes
- Started by Urs
- Comments 30
- Last comment by Urs
- Last Active Jul 6th 2022

for ease of linking I gave

*fundamental theorem of finitely generated abelian groups*a stubby entry of its own.In the course of this I also created a stub for

*structure theorem for finitely generated modules over a principal ideal domain*which used to be requested at*principal ideal domain*.

- Discussion Type
- discussion topicPaolo Aluffi
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topiccyclic group
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Jul 6th 2022

at

*cyclic group*there had been a typo that said “free group” instead of “cyclic group” (in the Examples-section). I have fixed that.Somehow I think this entry could be organized differently, but I won’t do that now.

- Discussion Type
- discussion topicabsolute value
- Category Latest Changes
- Started by Urs
- Comments 31
- Last comment by nLab edit announcer
- Last Active Jul 6th 2022

created absolute value and a stubby Ostrowski’s theorem

- Discussion Type
- discussion topicreal square root function
- Category Latest Changes
- Started by nLab edit announcer
- Comments 5
- Last comment by nLab edit announcer
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicadiabatic quantum computation
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicIntroduction to Homotopy Type Theory
- Category Latest Changes
- Started by nLab edit announcer
- Comments 31
- Last comment by Urs
- Last Active Jul 6th 2022

- Discussion Type
- discussion topicspinning particle
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Jul 6th 2022

added pointer to today’s

- Krzysztof Andrzejewski, Cezary Gonera, Joanna Goner, Piotr Kosinski, Pawel Maslanka,
*Spinning particles, coadjoint orbits and Hamiltonian formalism*(arXiv:2008.09478)

- Krzysztof Andrzejewski, Cezary Gonera, Joanna Goner, Piotr Kosinski, Pawel Maslanka,

- Discussion Type
- discussion topicinternal category
- Category Latest Changes
- Started by Urs
- Comments 79
- Last comment by nLab edit announcer
- Last Active Jul 5th 2022

I edited the formatting of internal category a bit and added a link to internal infinity-groupoid

it looks like the first query box discussion there has been resolved. Maybe we can remove that box now?

- Discussion Type
- discussion topico-minimal structure
- Category Latest Changes
- Started by Todd_Trimble
- Comments 9
- Last comment by Urs
- Last Active Jul 5th 2022

I started some short articles on o-minimal structure and structure (model theory).

- Discussion Type
- discussion topicsplit idempotent
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Keith Harbaugh
- Last Active Jul 5th 2022

I have added to the entry

*split idempotent*the statement (here) that in a triangulated category in which the direct sum of two triangles is a triangle, then idempotents split.(Maybe that should rather go into the entry

*Cauchy complete category*?)

- Discussion Type
- discussion topicA-n space
- Category Latest Changes
- Started by Mike Shulman
- Comments 6
- Last comment by Urs
- Last Active Jul 5th 2022

- Discussion Type
- discussion topicA-infinity-algebra
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 5th 2022

I have fixed these pointers (there was previously only the first but with DOI pointing to the second):

Jim Stasheff,

*Homotopy associativity of H-spaces I*, Trans. Amer. Math. Soc.**108**2 (1963) 275-292 [doi:10.2307/1993608]Jim Stasheff,

*Homotopy associativity of H-spaces II***108**2 (1963) 293-312 [doi:10.2307/1993609, doi:10.1090/S0002-9947-1963-0158400-5]

- Discussion Type
- discussion topicA4-spatial groupoid > history
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Urs
- Last Active Jul 5th 2022

- Discussion Type
- discussion topiccondensed spectrum
- Category Latest Changes
- Started by nLab edit announcer
- Comments 8
- Last comment by dagurasgeirsson
- Last Active Jul 5th 2022

- Discussion Type
- discussion topiccondensed infinity-groupoid
- Category Latest Changes
- Started by nLab edit announcer
- Comments 7
- Last comment by dagurasgeirsson
- Last Active Jul 5th 2022

- Discussion Type
- discussion topicmathematics presented in homotopy type theory
- Category Latest Changes
- Started by David_Corfield
- Comments 38
- Last comment by Mike Shulman
- Last Active Jul 5th 2022

- Discussion Type
- discussion topicHecke correspondence
- Category Latest Changes
- Started by Anton Hilado
- Comments 2
- Last comment by Anton Hilado
- Last Active Jul 4th 2022

- Discussion Type
- discussion topicparametric right adjoint
- Category Latest Changes
- Started by Mike Shulman
- Comments 16
- Last comment by Tim Campion
- Last Active Jul 4th 2022

Added alternative terminology “local right adjoint” and “strongly cartesian monad” from Berger-Mellies-Weber. They claim the former “has become the more accepted terminology” than “parametric right adjoint”; does anyone know other references to support this? (I think it’s certainly more logical, in that it fits with the general principle of “local” meaning “on slice categories” — not to be confused with the different general principle of “local” meaning “in hom-objects”.)

- Discussion Type
- discussion topiclocal Langlands conjecture
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 30
- Last comment by Anton Hilado
- Last Active Jul 4th 2022

This article has a weird claim on top, highlighted in yellow (see the second line):

Redirected from “local Langlands correspondence”.

Note: local Langlands conjecture and local Langlands conjecture both redirect for “local Langlands correspondence”.

- Discussion Type
- discussion topicmoduli stack of L-parameters
- Category Latest Changes
- Started by Anton Hilado
- Comments 4
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicfield
- Category Latest Changes
- Started by Mike Shulman
- Comments 11
- Last comment by nLab edit announcer
- Last Active Jul 3rd 2022

I added to field a mention of some other constructive variants of the definition, with a couple more references.

- Discussion Type
- discussion topicFargues-Fontaine curve
- Category Latest Changes
- Started by Anton Hilado
- Comments 8
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicMordell-Weil theorem
- Category Latest Changes
- Started by Anton Hilado
- Comments 1
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicErich Hecke
- Category Latest Changes
- Started by Anton Hilado
- Comments 2
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicJennifer Balakrishnan
- Category Latest Changes
- Started by Anton Hilado
- Comments 2
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicBrian Lawrence
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicAkshay Venkatesh
- Category Latest Changes
- Started by Anton Hilado
- Comments 4
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicEnrico Bombieri
- Category Latest Changes
- Started by Anton Hilado
- Comments 2
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicMordell conjecture
- Category Latest Changes
- Started by Anton Hilado
- Comments 15
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicAndrew Snowden
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicarithmetic gauge theory
- Category Latest Changes
- Started by Anton Hilado
- Comments 12
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topiccancellative element of a commutative ring
- Category Latest Changes
- Started by nLab edit announcer
- Comments 16
- Last comment by Guest
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicnumber theory
- Category Latest Changes
- Started by Stephan A Spahn
- Comments 4
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

I created Galois module. I also added further references to p-divisible group; in particular section 4.2 of Lurie’s survey of elliptic cohomology gives some generalization of the classical theory. I started also a page with -the somehow unfortunate- title relations of certain classes of group schemes- I intended it to give an overview and examples of the basic kinds of group schemes occurring in classical (algebraic) number theory (the page contains more or less two specific examples; so there is still development potential).

- Discussion Type
- discussion topicWiles' proof of Fermat's last theorem
- Category Latest Changes
- Started by Anton Hilado
- Comments 2
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topiccusp form
- Category Latest Changes
- Started by Anton Hilado
- Comments 1
- Last comment by Anton Hilado
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicarithmetic Chern-Simons theory
- Category Latest Changes
- Started by David_Corfield
- Comments 6
- Last comment by Urs
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicregular element
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Jul 3rd 2022

- Discussion Type
- discussion topicmultiplicative subset
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Jul 3rd 2022

cross linking filter of a ring, and explaining that depending on the the definition, multiplicative subsets form a subsemigroup or a submonoid of the ring.

different anonymous person

- Discussion Type
- discussion topicfilter of a ring
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active Jul 3rd 2022