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- Discussion Type
- discussion topicweakly separated space
- Category Latest Changes
- Started by nLab edit announcer
- Comments 2
- Last comment by Todd_Trimble
- Last Active Jun 9th 2019

- Discussion Type
- discussion topiclocale
- Category Latest Changes
- Started by Urs
- Comments 21
- Last comment by Mike Shulman
- Last Active Jun 8th 2019

added to locale a section relation to toposes stating localic reflection

- Discussion Type
- discussion topicBoolean category
- Category Latest Changes
- Started by nLab edit announcer
- Comments 11
- Last comment by Urs
- Last Active Jun 8th 2019

This is my first hook to the n-lab, I am pretty sure that isomorphism is an overly strong condition, and that any is a too weak restriction.

Please see the wikipedia article on the principle of bivalence. https://en.wikipedia.org/wiki/Principle_of_bivalence

I am unsure as how to proceeed.

vukovinski

- Discussion Type
- discussion topic(infinity,0)-category
- Category Latest Changes
- Started by jesuslop
- Comments 1
- Last comment by jesuslop
- Last Active Jun 8th 2019

- Discussion Type
- discussion topicvukovinski
- Category Latest Changes
- Started by nLab edit announcer
- Comments 8
- Last comment by Richard Williamson
- Last Active Jun 8th 2019

- Discussion Type
- discussion topicoriented link diagram
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Jun 7th 2019

- Discussion Type
- discussion topiccryptography
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Jun 7th 2019

Stub. For now just recording links which go beyond the scope of arithmetic cryptography.

- Discussion Type
- discussion topicadjoint functor
- Category Latest Changes
- Started by Urs
- Comments 46
- Last comment by David_Corfield
- Last Active Jun 7th 2019

added at adjoint functor

more details in the section In terms of universal arrows;

a bit in the section Examples

- Discussion Type
- discussion topictemporal logic
- Category Latest Changes
- Started by David_Corfield
- Comments 6
- Last comment by David_Corfield
- Last Active Jun 7th 2019

I added a couple of references for the claim

There is a Curry–Howard correspondence between linear-time temporal logic (LTL) and functional reactive programming (FRP).

How about for CLT and CLT* (in the computation tree logic section)?

Were we looking to integrate this section with the one above on temporal type theory as an adjoint logic, could there be a way via some branching representation of our type $Time$ as a tree?

I see Joachim Kock has an interesting way of presenting trees.

- Discussion Type
- discussion topicRadu Diaconescu
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jun 6th 2019

brief

`category:people`

-entry for hyperlinking references at*Diaconescu’s theorem*and*Diaconescu-Goodman-Myhill theorem*

- Discussion Type
- discussion topicDiaconescu-Goodman-Myhill theorem
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jun 6th 2019

splitting this off from

*excluded middle*so that we can disambiguate from*Diaconescu’s theorem*in topos theory

- Discussion Type
- discussion topicexcluded middle
- Category Latest Changes
- Started by Mike Shulman
- Comments 8
- Last comment by Urs
- Last Active Jun 6th 2019

I added to excluded middle a discussion of the constructive proof of double-negated LEM and how it is a sort of “continuation-passing” transform.

- Discussion Type
- discussion topicnon-geometric string vacuum
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Jun 6th 2019

- Discussion Type
- discussion topicexperiments -- contents
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Jun 6th 2019

- Discussion Type
- discussion topicBaBar experiment
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Jun 6th 2019

for completeness and for hyperlinkinks at

*B-meson*and*flavour anomaly*

- Discussion Type
- discussion topicflavour anomaly
- Category Latest Changes
- Started by Urs
- Comments 74
- Last comment by Urs
- Last Active Jun 6th 2019

- Discussion Type
- discussion topicmeager set
- Category Latest Changes
- Started by Dmitri Pavlov
- Comments 1
- Last comment by Dmitri Pavlov
- Last Active Jun 5th 2019

- Discussion Type
- discussion topicnowhere dense set
- Category Latest Changes
- Started by Mike Shulman
- Comments 2
- Last comment by Dmitri Pavlov
- Last Active Jun 5th 2019

Moved nowhere dense set out of dense subspace in a stub.

- Discussion Type
- discussion topichomotopical algebraic quantum field theory
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Jun 5th 2019

On occasion of Alexander Schenkel’s most recent talk (here) I am finally splitting off an entry

*homotopical algebraic quantum field theory*from*AQFT*.

- Discussion Type
- discussion topicSullivan model of a spherical fibration
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active Jun 5th 2019

- Discussion Type
- discussion topicSO(8)
- Category Latest Changes
- Started by Urs
- Comments 12
- Last comment by Urs
- Last Active Jun 5th 2019

- Discussion Type
- discussion topicSO(4)
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Jun 5th 2019

in order to have a good place to record the diagram:

$\array{ ( q_1, q_2 ) &\mapsto& (x \mapsto q_1 \cdot x \cdot \overline{q}_2) \\ Sp(1) \times Sp(1) &\overset{\simeq}{\longrightarrow}& Spin(4) \\ \big\downarrow && \big\downarrow \\ Sp(1)\cdot Sp(1) &\overset{\simeq}{\longrightarrow}& SO(4) }$

- Discussion Type
- discussion topicFrank Waaldijk
- Category Latest Changes
- Started by fwaaldijk
- Comments 1
- Last comment by fwaaldijk
- Last Active Jun 4th 2019

- Discussion Type
- discussion topicJoost Nuiten
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Jun 3rd 2019

- Discussion Type
- discussion topicNavier-Stokes equation
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Jun 3rd 2019

stub, for the moment just so as to record this reference:

- Terence Tao,
*Searching for singularities in the Navier–Stokes equations*, Nature Reviews Physics (2019) (doi:10.1038/s42254-019-0068-9, pdf)

- Terence Tao,

- Discussion Type
- discussion topicsuplattice
- Category Latest Changes
- Started by John Baez
- Comments 2
- Last comment by Todd_Trimble
- Last Active Jun 2nd 2019

- Discussion Type
- discussion topicXena project
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by atmacen
- Last Active Jun 2nd 2019

- Discussion Type
- discussion topicSmall fix: meet's definition
- Category Latest Changes
- Started by kostiantyn.rybnikov
- Comments 2
- Last comment by Todd_Trimble
- Last Active Jun 2nd 2019

- Should we replace "to all the elements in the set" with "to all the elements in the subset" at meet's definition?

> In a preordered set or partially ordered set then the meet or infimum of a subset of elements is, if it exists, the largest element which is smaller or equal to all the elements in the set. If this element is member of the original subset, then it is also called the minimum of that subset.

https://ncatlab.org/nlab/show/meet

Thank you!

- Discussion Type
- discussion topicmeet
- Category Latest Changes
- Started by Todd_Trimble
- Comments 1
- Last comment by Todd_Trimble
- Last Active Jun 2nd 2019

- Discussion Type
- discussion topicKaroubi envelope
- Category Latest Changes
- Started by David_Corfield
- Comments 2
- Last comment by Urs
- Last Active Jun 1st 2019

Added reference to a generalization of the Karoubi envelope for n-categories in

- Davide Gaiotto, Theo Johnson-Freyd,
*Condensations in higher categories*, (arXiv:1905.09566)

- Davide Gaiotto, Theo Johnson-Freyd,