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- Discussion Type
- discussion topicSakura Schäfer-Nameki
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active 1 hour ago

- Discussion Type
- discussion topiccohomology of knot graph complex is weight systems on chord diagrams
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 hours ago

starting something, to record Prop. 7.6 in

- Alberto Cattaneo, Paolo Cotta-Ramusino, Riccardo Longoni,
*Configuration spaces and Vassiliev classes in any dimension*, Algebr. Geom. Topol. 2 (2002) 949-1000 (arXiv:math/9910139)

still need to add details – not done yet

- Alberto Cattaneo, Paolo Cotta-Ramusino, Riccardo Longoni,

- Discussion Type
- discussion topicdependent type theoretic methods in natural language semantics
- Category Latest Changes
- Started by David_Corfield
- Comments 26
- Last comment by Urs
- Last Active 5 hours ago

I thought this should be better developed, and it is. Following the work of Sundholm and Ranta, several people are trying to use dependent type theory to understand natural language. This involves a range of things philosophers care about: anaphora, polysemy, modality, factivity, etc.

It should be interesting to bring this work into contact with the work here on dependent type theory in mathematics and physics. Already I see an overlap in the analysis of modality via a type of worlds, between us here and them in Resolving Modal Anaphora in Dependent Type Semantics on p. 89.

So I’ve started a page dependent type theoretic methods in natural language semantics to list references, and later results.

- Discussion Type
- discussion topictype theory
- Category Latest Changes
- Started by Mike Shulman
- Comments 90
- Last comment by atmacen
- Last Active 16 hours ago

I incorporated some of my spiel from the blog into the page type theory.

- Discussion Type
- discussion topicquantization of Yang-Mills theory
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by David_Corfield
- Last Active 20 hours ago

I keep having the need to point to something like mass gap problem. So now I created a stub for it, just so that the links works. Has to be expanded, clearly.

- Discussion Type
- discussion topicholographic entanglement entropy
- Category Latest Changes
- Started by Urs
- Comments 7
- 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 topicstring bit model
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 1 day ago

cross-linked with

*single trace observables*, copied over the relevant paragraphs from there to a new section here:*Via single trace observables under AdS/CFT*

- Discussion Type
- discussion topicweight system
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active 1 day ago

- Discussion Type
- discussion topicAufhebung
- Category Latest Changes
- Started by Urs
- Comments 75
- Last comment by Thomas Holder
- Last Active 1 day ago

Thomas Holder has been working on

*Aufhebung*. I have edited the formatting a little (added hyperlinks and more Definition-environments, added another subsection header and some more cross-references, cross-linked with*duality of opposites*).

- Discussion Type
- discussion topicsuper Lie algebra
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active 2 days ago

added a few references and links to super Lie algebra

- Discussion Type
- discussion topicsuper vector space
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 2 days ago

I gave the entry

*super vector space*some expositional background and a more detailed (pedantic) definition.

- Discussion Type
- discussion topicjet bundle
- Category Latest Changes
- Started by Urs
- Comments 59
- Last comment by timhosgood
- Last Active 2 days ago

stub for jet bundle

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

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

added this pointer:

- Damien Calaque, Pavel Etingof,
*Lectures on tensor categories*, IRMA Lectures in Mathematics and Theoretical Physics 12, 1-38 (2008) (arXiv:math/0401246)

- Damien Calaque, Pavel Etingof,

- Discussion Type
- discussion topicstring diagram
- Category Latest Changes
- Started by nLab edit announcer
- Comments 26
- Last comment by Urs
- Last Active 2 days ago

- Discussion Type
- discussion topicmetric Lie algebra
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 2 days ago

- Discussion Type
- discussion topicmetric Lie representation
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 2 days ago

starting a small entry here, for ease of hyperlinking. This is to go along with

*metric Lie algebra*

- Discussion Type
- discussion topicM-brane 3-algebra
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active 2 days ago

am splitting this off from n-Lie algebra (which should better be renamed to Filippov algebra)

– am being interrupted now – not done yet…

- Discussion Type
- discussion topicgerbe (general idea)
- Category Latest Changes
- Started by jesuslop
- Comments 1
- Last comment by jesuslop
- Last Active 2 days ago

- Discussion Type
- discussion topicJohn Faulkner
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 3 days ago

brief

`category:people`

-entry for hyperlinking (at*Faulkner construction*, presently redirecting to*M2-brane 3-algebra*) this reference:- John Faulkner,
*On the geometry of inner ideals*, Journal of Algebra Volume 26, Issue 1, July 1973, Pages 1-9 (doi:10.1016/0021-8693(73)90032-X)

(I hope I have identified the author’s webpage correctly – if anyone knows, please check)

- John Faulkner,

- Discussion Type
- discussion topicRoger Penrose
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active 3 days ago

added some actual text to the category:people entry

*Roger Penrose*

- Discussion Type
- discussion topiclocally presentable categories - introduction
- Category Latest Changes
- Started by Urs
- Comments 13
- Last comment by Mike Shulman
- Last Active 3 days ago

I was looking for a place to record a somewhat more global overview of the notion of

*locally presentable category*, its related notions and its generalizations to higher category theory. But somehow all of the existing entries feel too narrow in focus to accomodate this. So I ended up creating now a new entry titledThink of this as accomodating material such as one might present in a seminar talk that is meant to bring people with some basic background up to speed with the relevant notions, without going into the wealth of technical lemmas.

I only just started. Will continue in a moment after a short break…

- Discussion Type
- discussion topiccartesian differential category
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 1
- Last comment by Dmitri Pavlov
- Last Active 3 days ago

- Discussion Type
- discussion topicPaul de Medeiros
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 3 days ago

- Discussion Type
- discussion topicSergey Cherkis
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 3 days ago

brief

`category:people`

-entry for hyperlinking references at*M2-brane 3-algebra*

- Discussion Type
- discussion topicshape of an (infinity,1)-topos
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 3 days ago

- Discussion Type
- discussion topicmetric space
- Category Latest Changes
- Started by Mike Shulman
- Comments 6
- Last comment by DavidRoberts
- Last Active 3 days ago

I’ve removed this query box from metric space and incorporated its information into the text:

Mike: Perhaps it would be more accurate to say that the symmetry axiom gives us enriched $\dagger$-categories?

*Toby*: Yeah, that could work. I was thinking of arguing that it makes sense to enrich groupoids in any monoidal poset, cartesian or otherwise, since we can write down the operations and all equations are trivial in a poset. But maybe it makes more sense to call those enriched $\dagger$-categories.

- Discussion Type
- discussion topicclone
- Category Latest Changes
- Started by zskoda
- Comments 14
- Last comment by Mike Shulman
- Last Active 4 days ago

New stub for the notion of clone in universal algebra, including a reference relating it to operads.

- Discussion Type
- discussion topicNahm's equation
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active 4 days ago

- Discussion Type
- discussion topicCoulomb branch
- Category Latest Changes
- Started by nLab edit announcer
- Comments 4
- Last comment by Urs
- Last Active 4 days ago