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- Discussion Type
- discussion topicrelative adjoint functor
- Category Latest Changes
- Started by Peter Heinig
- Comments 5
- Last comment by RodMcGuire
- Last Active 3 hours ago

Made some some small improvements (ordering of sections, note on how the definition defaults to the usual definition of adjoints, fixing broken link in the references, etc) in relative adjoint functor.

- Discussion Type
- discussion topicdouble category of algebras
- Category Latest Changes
- Started by Mike Shulman
- Comments 4
- Last comment by varkor
- Last Active 4 hours ago

New page: double category of algebras.

- Discussion Type
- discussion topiccohomotopy
- Category Latest Changes
- Started by Urs
- Comments 45
- Last comment by perezl.alonso
- Last Active 6 hours ago

At the old entry

*cohomotopy*used to be a section on how it may be thought of as a special case of non-abelian cohomology. While I (still) think this is an excellent point to highlight, re-reading this old paragraph now made me feel that it was rather clumsily expressed. Therefore I have rewritten (and shortened) it, now the third paragraph of the Idea-section.(We had had long discussion about this entry back in the days, but it must have been before we switched to nForum discussion, because on the nForum there seems to be no trace of it.)

- Discussion Type
- discussion topicfibration of quasi-categories
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Hurkyl
- Last Active 9 hours ago

am starting fibrations of quasi-categories

- Discussion Type
- discussion topicspherical function
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 13 hours ago

- Discussion Type
- discussion topicmapping class group
- Category Latest Changes
- Started by perezl.alonso
- Comments 1
- Last comment by perezl.alonso
- Last Active 23 hours ago

Is there a particular reference where these (or rather, their super analogs) are computed for super Riemann surfaces?

- Discussion Type
- discussion topicspatial locale
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 17
- Last comment by Dmitri Pavlov
- Last Active 1 day ago

- Discussion Type
- discussion topicsemidirect product group
- Category Latest Changes
- Started by nLab edit announcer
- Comments 11
- Last comment by nLab edit announcer
- Last Active 1 day ago

- Discussion Type
- discussion topicinequality space
- Category Latest Changes
- Started by nLab edit announcer
- Comments 3
- Last comment by nLab edit announcer
- Last Active 1 day ago

- Discussion Type
- discussion topicmodular theory
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Tom Mainiero
- Last Active 1 day ago

- Discussion Type
- discussion topicenveloping von Neumann algebra
- Category Latest Changes
- Started by nLab edit announcer
- Comments 3
- Last comment by Tom Mainiero
- Last Active 2 days ago

- Discussion Type
- discussion topicprealgebra real number
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active 2 days ago

- Discussion Type
- discussion topicepimorphism
- Category Latest Changes
- Started by Urs
- Comments 16
- Last comment by nLab edit announcer
- Last Active 2 days ago

felt like adding a handful of basic properties to epimorphism

- Discussion Type
- discussion topicSurj
- Category Latest Changes
- Started by David_Corfield
- Comments 8
- Last comment by varkor
- Last Active 2 days ago

- Discussion Type
- discussion topicDirac manifold
- Category Latest Changes
- Started by perezl.alonso
- Comments 1
- Last comment by perezl.alonso
- Last Active 2 days ago

pointer

- Saskia Demulder, Thomas Raml.
*Poisson-Lie T-duality defects and target space fusion*(2022). (arXiv:2208.04662).

- Saskia Demulder, Thomas Raml.

- Discussion Type
- discussion topicconformal invariance and scale invariance
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active 3 days ago

added pointer to:

- Martin Lüscher, Gerhard Mack:
*Global Conformal Invariance in Quantum Field Theory*, Comm. Math. Phys.**41**3 (1975) 203-234 [doi:10.1007/BF01608988, jstor:cmp/1103898909, inspire:90687]

- Martin Lüscher, Gerhard Mack:

- Discussion Type
- discussion topicdistributivity pullback
- Category Latest Changes
- Started by Mike Shulman
- Comments 7
- Last comment by varkor
- Last Active 3 days ago

- Discussion Type
- discussion topiclocally cartesian closed category
- Category Latest Changes
- Started by Todd_Trimble
- Comments 5
- Last comment by nLab edit announcer
- Last Active 3 days ago

In locally cartesian closed category, I wrote out an explicit proof that pullback functors $f^\ast \colon C/Y \to C/X$ between slices preserve exponentials (so that Frobenius reciprocity is satisfied).

- Discussion Type
- discussion topicD-brane
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by perezl.alonso
- Last Active 3 days ago

- Discussion Type
- discussion topicfactorization algebra
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by zskoda
- Last Active 4 days ago

added the full definition to factorization algebra

- Discussion Type
- discussion topicfull image
- Category Latest Changes
- Started by varkor
- Comments 3
- Last comment by J-B Vienney
- Last Active 4 days ago

- Discussion Type
- discussion topicAskey-Wilson polynomial
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

We already have main references at Richard Askey, so why not ?

- Discussion Type
- discussion topicRichard Askey
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicGeorge Andrews
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicMasatoshi Noumi
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicYasuhiko Yamada
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active 4 days ago

brief

`category:people`

-entry for hyperlinking references at*elliptic genus*

- Discussion Type
- discussion topicRobinson-Schensted-Knuth correspondence
- Category Latest Changes
- Started by David_Corfield
- Comments 4
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicMacdonald Constant-Term Conjecture
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

Not to confuse with Macdonald conjecture on plane partitions.

- Discussion Type
- discussion topicMacdonald conjecture on plane partitions
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicfunctor with smash products
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by zskoda
- Last Active 4 days ago

started a minimum at

*functor with smash products*(the realization of ring spectra in terms of lax monoidal functors)In the end this is entirely a story about monoids with respect to Day convolution tensor products. I suppose there is room to say this yet a bit more general abstractly than MMSS00 did.

- Discussion Type
- discussion topicDavid P. Robbins
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicdendroidal set
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by nLab edit announcer
- Last Active 4 days ago

added at dendroidal set

a section on the relation to simplicial sets

a section on the symmetric monoidal structure on the cat of dendroidal sets

(also added a stubby "overview" section to model structure on dendroidal sets)

- Discussion Type
- discussion topicoctahedron recurrence
- Category Latest Changes
- Started by zskoda
- Comments 2
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topiclax monoidal category
- Category Latest Changes
- Started by Mike Shulman
- Comments 19
- Last comment by varkor
- Last Active 4 days ago

- Discussion Type
- discussion topicGleb Koshevoy
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicDavid Speyer
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 4 days ago

- Discussion Type
- discussion topicLawvere-Tierney topology
- Category Latest Changes
- Started by Urs
- Comments 18
- Last comment by nLab edit announcer
- Last Active 5 days ago

I have expanded Lawvere-Tierney topology, also reorganized it in the process

- Discussion Type
- discussion topicfree coproduct completion
- Category Latest Changes
- Started by Urs
- Comments 20
- Last comment by varkor
- Last Active 5 days ago

some bare minimum on the free coproduct cocompletion.

The term used to redirect to the entry

*free cartesian category*, where however the simple idea of free coproduct completion wasn’t really brought out.

- Discussion Type
- discussion topiclocally presentable category
- Category Latest Changes
- Started by Tobias Fritz
- Comments 20
- Last comment by qschroed
- Last Active 5 days ago

- In the definition, the article states "every object in C is a small object (which follows from 2 and 3)". The bracketed remark doesn't seem quite right to me, since neither 2 nor 3 talk about smallness of objects. Presumably this should better be phrased as in A.1.1 of HTT, "assuming 3, this is equivalent to the assertion that every object in S is small".

Am I right? I don't (yet) feel confident enough with my category theory to change this single-handedly.

- Discussion Type
- discussion topicMartin Lüscher
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicRobert Lee Wilson
- Category Latest Changes
- Started by zskoda
- Comments 2
- Last comment by Urs
- Last Active 6 days ago

Person entry.

Warning: we have a webpage for another algebraist, the group theorist Robert A. Wilson, and elsewhere in the $n$Lab Robert Wilson shortcut is carelessly used for the latter. People tend to shorten links in $n$Lab and the confusion and illegal links might occur in this case. Maybe we should not use version without middle initial for these two guys in links.

- Discussion Type
- discussion topicPhilippe Di Francesco
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active 6 days ago

- Discussion Type
- discussion topicgroup-completed configuration space of points
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active 6 days ago

- Discussion Type
- discussion topicDodgson condensation
- Category Latest Changes
- Started by zskoda
- Comments 2
- Last comment by zskoda
- Last Active 6 days ago

In statu nascendi.

A method for calculating determinants. It is related to cluster algebras and a special case of Sylvester identity.

- Discussion Type
- discussion topicmatroid
- Category Latest Changes
- Started by Todd_Trimble
- Comments 22
- Last comment by varkor
- Last Active 6 days ago

I have been adding some material to matroid. I haven’t gotten around to defining oriented matroid yet (and of course there’s much besides to add).

- Discussion Type
- discussion topicBoolean algebra
- Category Latest Changes
- Started by Todd_Trimble
- Comments 4
- Last comment by J-B Vienney
- Last Active 6 days ago

Added more material to Boolean algebra, particularly the principle of duality and the connection to Boolean rings, and a wee bit of material on Stone duality.

Stone duality deserves greater expansion, bringing out the dualities via ambimorphic (ahem, schizophrenic) structures on the 2-element set, and mentioning the connection to Chu spaces. Another day, another dollar.

- Discussion Type
- discussion topicglobal equivariant homotopy theory
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by nLab edit announcer
- Last Active 7 days ago

I should say – for those watching the logs and wondering – that I started editing the entry

*global equivariant homotopy theory*such as to reflect Charles Rezk’s account in a coherent way.But I am not done yet. The entry has now some of the key basics, but is still missing the general statement in its relation to orbispaces. Also some harmonizing of the whole entry may be necessary now, as I moved around some stuff.

So better don’t look at it yet. I hope to bring it into shape tomorrow or so.

(In the process I have split off

*global orbit category*now.)

- Discussion Type
- discussion topicC-star-algebra
- Category Latest Changes
- Started by Urs
- Comments 13
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topiccoefficient system
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 7 days ago

- Discussion Type
- discussion topicG-∞-category
- Category Latest Changes
- Started by nLab edit announcer
- Comments 5
- Last comment by nLab edit announcer
- Last Active 7 days ago

- Discussion Type
- discussion topicindexed tensor product
- Category Latest Changes
- Started by nLab edit announcer
- Comments 0
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicAaron Naber
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicMichael T. Anderson
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicRicci curvature
- Category Latest Changes
- Started by Daniel Luckhardt
- Comments 7
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicGiry monad
- Category Latest Changes
- Started by zskoda
- Comments 73
- Last comment by nLab edit announcer
- Last Active 7 days ago

Added a reference of Robert Furber, Bart Jacobs at Giry monad.

- Discussion Type
- discussion topicgraded monad
- Category Latest Changes
- Started by David_Corfield
- Comments 24
- Last comment by varkor
- Last Active 7 days ago

- Discussion Type
- discussion topicStephen Hawking
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicPenrose singularity theorem
- Category Latest Changes
- Started by Urs
- Comments 14
- Last comment by Urs
- Last Active 7 days ago

created a minimum at

*Penrose-Hawking singularity theorem*

- Discussion Type
- discussion topicHawking radiation
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicGabriel Wong
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago