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- Discussion Type
- discussion topiccoset WZW model
- Category Latest Changes
- Started by perezl.alonso
- Comments 1
- Last comment by perezl.alonso
- Last Active Sep 2nd 2024

- Discussion Type
- discussion topicChetan Vuppulury
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
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- Discussion Type
- discussion topicNivedita
- Category Latest Changes
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- Discussion Type
- discussion topicCameron Krulewski
- Category Latest Changes
- Started by Urs
- Comments 1
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- Discussion Type
- discussion topicBrett Hungar
- Category Latest Changes
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- Comments 1
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- Discussion Type
- discussion topicGiovanni Ferrer
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
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- Discussion Type
- discussion topicdagger category
- Category Latest Changes
- Started by Urs
- Comments 43
- Last comment by nLab edit announcer
- Last Active Sep 2nd 2024

I took the liberty of incorporating material from Andre Joyal's latest message to the CatTheory mailing list into the entry dagger-category:

created sections

- Discussion Type
- discussion topicWedderburn-Artin theorem
- Category Latest Changes
- Started by John Baez
- Comments 6
- Last comment by Urs
- Last Active Sep 2nd 2024

- Discussion Type
- discussion topicJoseph Wedderburn
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
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- Discussion Type
- discussion topicCauchy structure
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active Sep 2nd 2024

- Discussion Type
- discussion topicJean-Pierre Serre
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 2nd 2024

- Discussion Type
- discussion topicEugene B. Dynkin
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 2nd 2024

- Discussion Type
- discussion topicindexing system
- Category Latest Changes
- Started by nLab edit announcer
- Comments 7
- Last comment by nLab edit announcer
- Last Active Sep 2nd 2024

- Discussion Type
- discussion topicKreisel-Lacombe-Shoenfield-Tseitin theorem
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Sep 1st 2024

- Discussion Type
- discussion topicDrinfeld center
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by perezl.alonso
- Last Active Sep 1st 2024

- Discussion Type
- discussion topicLie algebra
- Category Latest Changes
- Started by Urs
- Comments 16
- Last comment by Urs
- Last Active Sep 1st 2024

added to

*Lie algebra*a brief paragraph*general abstract perspective*to go along with this MO reply

- Discussion Type
- discussion topicstring diagram
- Category Latest Changes
- Started by nLab edit announcer
- Comments 51
- Last comment by Urs
- Last Active Sep 1st 2024

- Discussion Type
- discussion topicYuli Rudyak
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 1st 2024

- Discussion Type
- discussion topicTractatus Logico-Philosophicus
- Category Latest Changes
- Started by DavidRoberts
- Comments 1
- Last comment by DavidRoberts
- Last Active Sep 1st 2024

- Discussion Type
- discussion topicShum's theorem
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Sep 1st 2024

- Discussion Type
- discussion topicpartial order
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by zskoda
- Last Active Aug 31st 2024

added statement of existence of linear extensions (here)

Will give this its own entry at

*linear extension of a partial order*, for ease of referencing

- Discussion Type
- discussion topicphilosophy - contents
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Urs
- Last Active Aug 31st 2024

[spam]

- Discussion Type
- discussion topictangle
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 5
- Last comment by Urs
- Last Active Aug 31st 2024

- Discussion Type
- discussion topicLudwig Wittgenstein
- Category Latest Changes
- Started by J-B Vienney
- Comments 2
- Last comment by Urs
- Last Active Aug 31st 2024

- Discussion Type
- discussion topicribbon category
- Category Latest Changes
- Started by nLab edit announcer
- Comments 9
- Last comment by Urs
- Last Active Aug 31st 2024

- Discussion Type
- discussion topicW algebra
- Category Latest Changes
- Started by zskoda
- Comments 2
- Last comment by perezl.alonso
- Last Active Aug 31st 2024

An early survey is

- Peter Bouwknegt, Kareljan Schoutens,
*W symmetry in conformal field theory*, Phys. Rep.**223**:4 (1993) 183–276 doi

- Peter Bouwknegt, Kareljan Schoutens,

- Discussion Type
- discussion topicsupergeometry of fermion fields -- references
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Aug 30th 2024

a bare list of references, to be

`!include`

-ed into the References-sections of relevant entries (such as at*supergeometry*and*fermion*), for ease of synchronization

- Discussion Type
- discussion topicsupergeometry
- Category Latest Changes
- Started by Urs
- Comments 12
- Last comment by Urs
- Last Active Aug 30th 2024

added to supergeometry a link to the recent talk

- Mikhail Kapranov,
*Categorification of supersymmetry and stable homotopy groups of spheres*(video)

- Mikhail Kapranov,

- Discussion Type
- discussion topicsupergroup
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Aug 30th 2024

Added the Yoneda-embedding way to talk about group objects and hence supergroups.

- Discussion Type
- discussion topicJoscha Diehl
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 30th 2024

- Discussion Type
- discussion topichigher parallel transport
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Aug 30th 2024

added pointer to

- Arthur Parzygnat,
*Two-dimensional algebra in lattice gauge theory*(arXiv:1802.01139)

which provides a wealth of computational details and illustrative graphics.

- Arthur Parzygnat,

- Discussion Type
- discussion topicspectrum of a commutative ring
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topiciterated localization
- Category Latest Changes
- Started by mattecapu
- Comments 9
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topicabstract rewriting system
- Category Latest Changes
- Started by J-B Vienney
- Comments 4
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topicBirkhoff's theorem
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topicAndrew Pressley
- Category Latest Changes
- Started by zskoda
- Comments 1
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- Discussion Type
- discussion topicGeorge David Birkhoff
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topicBirkhoff's subdirect representation theorem
- Category Latest Changes
- Started by zskoda
- Comments 3
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topicBirkhoff's HSP theorem
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
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- Discussion Type
- discussion topicsemiorthogonal decomposition
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Aug 30th 2024

- Discussion Type
- discussion topicmeasurable locale
- Category Latest Changes
- Started by TobyBartels
- Comments 15
- Last comment by DavidRoberts
- Last Active Aug 30th 2024

I wrote about Dmitri Pavlov’s concept of measurable locales.

- Discussion Type
- discussion topicdistributive law
- Category Latest Changes
- Started by Mike Shulman
- Comments 34
- Last comment by John Baez
- Last Active Aug 29th 2024

I added some simpler motivation in terms of the basic example to the beginning of distributive law.

- Discussion Type
- discussion topicmeasure theory
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

added publication data to:

- Simon Henry,
*Measure theory over boolean toposes*, Mathematical Proceedings of the Cambridge Philosophical Society Volume 163 Issue 1, 2016 (arXiv:1411.1605, doi:10.1017/S0305004116000700)

- Simon Henry,

- Discussion Type
- discussion topicAndrew Swan
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

brief

`category:people`

-entry for hyperlinking references at*Nielsen-Schreier theorem*

- Discussion Type
- discussion topicAndrej Bauer
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

Added reference

- {#BauerSwan18} Andrej Bauer and Andrew Swan,
*Every metric space is separable in function realizability*, 2018, (arxiv:1804.00427)

Anonymouse

- {#BauerSwan18} Andrej Bauer and Andrew Swan,

- Discussion Type
- discussion topicfunction realizability
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

I gather the following is true and is shown in Battenfield-Schröder-Simpson (pdf), but I haven’t really fully absorbed yet how $AdmRep$ is actually embedded in $RT(\mathcal{K}_2)$.

The subcategory on the effectively computable morphisms of the function realizability topos $RT(\mathcal{K}_2)$ is the Kleene-Vesley topos $KV$. The category of “admissible representations” $AdmRep$ (whose morphisms are computable functions (analysis), see there) is a reflective subcategory of $RT(\mathcal{K}_2)$ (BSS) and the restriction of that to $KV$ is $AdmRep_{eff}$

$\array{ AdmRep_{eff} &\hookrightarrow& KV \\ \downarrow && \downarrow \\ AdmRep &\hookrightarrow& RT(\mathcal{K}_2) }$

This is currently stated this way in the entry function ralizability and computable function (analysis), but please criticize/handle with care, I’ll try to further fine-tune as need be.

- Discussion Type
- discussion topicseparable metric space
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

- Discussion Type
- discussion topicclassical set
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

- Discussion Type
- discussion topicdecidable equality
- Category Latest Changes
- Started by Mike Shulman
- Comments 10
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

I added to decidable equality some remarks on the difference between the propositions-as-types version and the propositions-as-some-types version.

- Discussion Type
- discussion topicDold-Kan correspondence
- Category Latest Changes
- Started by Urs
- Comments 38
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

added reference to dendroidal version of Dold-Kan correspondence

- Discussion Type
- discussion topicgeneralized global symmetry
- Category Latest Changes
- Started by perezl.alonso
- Comments 39
- Last comment by perezl.alonso
- Last Active Aug 29th 2024

- Discussion Type
- discussion topicclosed monoidal category
- Category Latest Changes
- Started by Mike Shulman
- Comments 30
- Last comment by nLab edit announcer
- Last Active Aug 29th 2024

added to closed monoidal category a proof that the pointwise tensor product on a functor category with complete codomain is closed.

- Discussion Type
- discussion topicstringor bundle
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Aug 29th 2024

- Discussion Type
- discussion topicsuper-Minkowski Lie group -- example
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Aug 29th 2024

this is a bare section, spelling out in full detail the construction of the super Lie group integrating the translational part of the “supersymmetry algebra”, namely of the super Poincaré Lie algebra

(this is of course known to experts, but I am not aware of any literature showcasing how this works in full detail – if such literature exist, please drop a note [the group law itself appears in CAIP99 (2.1) (2.6)])

this entry is meant to be

`!include`

-ed as an Example-subsection into relevant entries, such as at*super translation group*

- Discussion Type
- discussion topicgroup-completed configuration space of points
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active Aug 28th 2024

- Discussion Type
- discussion topichomogeneous function
- Category Latest Changes
- Started by risingtides
- Comments 2
- Last comment by Urs
- Last Active Aug 28th 2024

- Discussion Type
- discussion topicEuler vector field
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 28th 2024

- Discussion Type
- discussion topicRichard Courant
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 28th 2024

- Discussion Type
- discussion topicdifferential calculus
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Urs
- Last Active Aug 28th 2024

wrote a few lines at differential calculus, just so that the link does point somewhere. Clearly just a stub, to be expanded.

- Discussion Type
- discussion topicsigma-complete Boolean algebra
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Aug 28th 2024