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- Discussion Type
- discussion topicAlain Joye
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago

- Discussion Type
- discussion topicopen quantum system
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 4 days ago

discovered that we have this old entry.

I touched the wording in the first paragraph (there is room to improve it further)

and took the liberty of deleting the second (which was trying to state a theorem but didn’t even declare its symbols and ended up being mainly a pointer to Schumacher & Westmoreland 2010, for which I have now added the publication data)

this entry remains a stub

- Discussion Type
- discussion topicquantum channels and decoherence -- section
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago

this is a bare sub-section — meant to be

`!include`

ed into relevant entries such as at*quantum channel*and at*quantum decoherence*— towards the theorem that quantum channels are exactly the “bath-averages of bath-coupled unitary evolutions”

- Discussion Type
- discussion topicquantum state monad
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active 4 days ago

Starting an entry (to rhyme on “quantum reader monad”) on the linear version of the costate comonad and how its coKleisli category on the tensor unit alone exhibits the structure of quantum observables.

- Discussion Type
- discussion topicspin^c
- Category Latest Changes
- Started by Urs
- Comments 14
- Last comment by DavidRoberts
- Last Active 4 days ago

I have split off spin^c from spin^c structure

- Discussion Type
- discussion topicArmin Frei
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago

- Discussion Type
- discussion topicMaciej Piróg
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago

- Discussion Type
- discussion topicMauro Jaskelioff
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 4 days ago

- Discussion Type
- discussion topicstrict inverse function
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 5 days ago

- Discussion Type
- discussion topicmonad (in computer science)
- Category Latest Changes
- Started by Urs
- Comments 43
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicDavid A. Espinosa
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicmonad transformer
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active 5 days ago

I have added (here) pointer to:

- Sergei Winitzki, Chapter 14 of:
*The Science of Functional Programming – A tutorial, with examples in Scala*(leanpub:sofp)

(This edit prompted by discussion in another thread of the same name: here)

- Sergei Winitzki, Chapter 14 of:

- Discussion Type
- discussion topicstrict proposition
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicstrict singleton
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 5 days ago

- Discussion Type
- discussion topicstochastic map
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicSusan Montgomery
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 5 days ago

- Discussion Type
- discussion topicgraphical quantum channel > history
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicSergey Fomin
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 5 days ago

- Discussion Type
- discussion topictotally positive matrix
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 5 days ago

- Discussion Type
- discussion topicGeorge Lusztig
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 5 days ago

- Discussion Type
- discussion topicClaus Michael Ringel
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active 5 days ago

- Discussion Type
- discussion topicJesper Cockx
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 5 days ago

created article for linking the reference

- Gaëtan Gilbert, Jesper Cockx, Matthieu Sozeau, Nicolas Tabareau,
*Definitional Proof-Irrelevance without K*. Proceedings of the ACM on Programming Languages, Volume 3, Issue POPL, Article 3, pp 1–28, January 2019. (doi:10.1145/3290316)

Anonymouse

- Gaëtan Gilbert, Jesper Cockx, Matthieu Sozeau, Nicolas Tabareau,

- Discussion Type
- discussion topictype of strict propositions
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 5 days ago

- Discussion Type
- discussion topicsquash type
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 5 days ago

- Discussion Type
- discussion topicendomorphism ring
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 5 days ago

stub for endomorphism ring

- Discussion Type
- discussion topicidentity function
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topicheterogeneous equality
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Urs
- Last Active 5 days ago

- Discussion Type
- discussion topictwo-type identity type
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 6 days ago

- Discussion Type
- discussion topicheterogeneous identity type
- Category Latest Changes
- Started by nLab edit announcer
- Comments 20
- Last comment by nLab edit announcer
- Last Active 6 days ago

- Discussion Type
- discussion topicJohn Major equality
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 6 days ago

- Discussion Type
- discussion topicConor McBride
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 6 days ago

- Discussion Type
- discussion topicfusion 2-category
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by perezl.alonso
- Last Active 6 days ago

A stub, for the moment just to have a place for recording a couple of references (which were previously at

*fusion category*.

- Discussion Type
- discussion topicspecial geometry
- Category Latest Changes
- Started by perezl.alonso
- Comments 1
- Last comment by perezl.alonso
- Last Active 6 days ago

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

- Discussion Type
- discussion topicinternal category
- Category Latest Changes
- Started by Urs
- Comments 89
- Last comment by Urs
- Last Active 6 days ago

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 topicBenno van den Berg
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by nLab edit announcer
- Last Active 6 days ago

Adding reference

- Benno van den Berg, Martijn den Besten,
*Quadratic type checking for objective type theory*(arXiv:2102.00905)

Anonymous

- Benno van den Berg, Martijn den Besten,

- Discussion Type
- discussion topicDutch Categories and Types Seminar
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active 7 days ago

- Discussion Type
- discussion topiccompact closed category
- Category Latest Changes
- Started by Noam_Zeilberger
- Comments 8
- Last comment by Urs
- Last Active 7 days ago

I added a note to compact closed category on the fact that the inclusion from compact closed categories into SMCCs has a left adjoint, pointing to an article by Day where he describes the free compact closed category over a closed symmetric monoidal category as a localization. Question: this left adjoint is not full, but I believe it is faithful – does anyone know how to prove that?

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

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

- Discussion Type
- discussion topicsynthetic algebraic geometry
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topictypal equality
- Category Latest Changes
- Started by nLab edit announcer
- Comments 4
- Last comment by Mike Shulman
- Last Active 7 days ago

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

- Discussion Type
- discussion topicsplit epimorphism
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by varkor
- Last Active 7 days ago

- Discussion Type
- discussion topicsplit monomorphism
- Category Latest Changes
- Started by varkor
- Comments 1
- Last comment by varkor
- Last Active 7 days ago

- Discussion Type
- discussion topicstore comonad
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicidentity type
- Category Latest Changes
- Started by Urs
- Comments 117
- Last comment by Urs
- Last Active 7 days ago

added to identity type a mentioning of the alternative definition in terms of inductive types (paths).

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

- Discussion Type
- discussion topicHeinz-Peter Breuer
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active 7 days ago

- Discussion Type
- discussion topicquantum decoherence
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active 7 days ago

added pointer to today’s

- Chris Nagele, Oliver Janssen, Matthew Kleban,
*Decoherence: A Numerical Study*(arXiv:2010.04803)

- Chris Nagele, Oliver Janssen, Matthew Kleban,

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

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

- Discussion Type
- discussion topicD=2 supergravity
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active 7 days ago

Added pointer to today’s

Guillaume Bossard, Franz Ciceri, Gianluca Inverso, Axel Kleinschmidt,

*Maximal $D=2$ supergravities from higher dimensions*[arXiv:2309.07232]Guillaume Bossard, Franz Ciceri, Gianluca Inverso, Axel Kleinschmidt,

*Consistent truncation of eleven-dimensional supergravity on $S^8 \times S^1$*[arXiv:2309.07233]

- Discussion Type
- discussion topicchord diagram
- Category Latest Changes
- Started by Noam_Zeilberger
- Comments 13
- Last comment by Urs
- Last Active 7 days ago

I created a short page for chord diagram, and also added a bit of relevant information to Vassiliev invariant.

- Discussion Type
- discussion topicGoodwillie calculus
- Category Latest Changes
- Started by Urs
- Comments 44
- Last comment by nonemenon
- Last Active Sep 14th 2023

stub for Goodwillie calculus

- Discussion Type
- discussion topicDrinfel'd double
- Category Latest Changes
- Started by Urs
- Comments 16
- Last comment by nLab edit announcer
- Last Active Sep 14th 2023

I gave

*Drinfel’d double*an Idea-section.Also moved a paragraph on module categories from the References to a Properties-section.

- Discussion Type
- discussion topiccyclotomic spectrum
- Category Latest Changes
- Started by Urs
- Comments 27
- Last comment by Urs
- Last Active Sep 14th 2023

Started a bare minimum at

*cyclotomic spectrum*. So far it’s essentially just a pointer to the canonical reference by Blumberg-Mandell. (Thomas Nikolaus and Peter Scholze have a new foundation of the theory in preparation for which notes however are not public yet, also Clark Barwick has something in preparation, for which you may find notes by looking at his website and being clever in deducing hidden URLs, he says.)For the moment the only fact that I have actually recorded in the entry is a fact that is trivial for anyone familiar with the theory,but which looks interesting from the point of view of the story at

*Generalized cohomology of M2/M5-branes (schreiber)*: the global equivariant sphere spectrum for all the cyclic groups (all the A-type finite groups in the ADE classification…) carries canonical cyclotomic structure and as such is the tensor unit among cyclotomic spectra.Apart from mentioning this, I have added brief cross-links with

*topological cyclic homology*,*equivariant sphere spectrum*,*cyclic group*and maybe other entries.

- Discussion Type
- discussion topicquantum cohomology ring
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Sep 14th 2023

stub for quantum sheaf cohomology

- Discussion Type
- discussion topicsolid functor
- Category Latest Changes
- Started by Mike Shulman
- Comments 8
- Last comment by varkor
- Last Active Sep 13th 2023

Created solid functor with an SVG graphic. The SVG editor is awesome! Even if it is still a little buggy.

- Discussion Type
- discussion topicstructural ZFC
- Category Latest Changes
- Started by nLab edit announcer
- Comments 6
- Last comment by nLab edit announcer
- Last Active Sep 13th 2023