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- Discussion Type
- discussion topicString bordism
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Mar 16th 2023

added pointer to:

- Michael Hill,
*The $String$ bordism of $B E_8$ and $B E_8 \times B E_8$ through dimension 14*, Ill. J. Math.**53**1 (2009) 183-196 [doi:10.1215/ijm/1264170845]

- Michael Hill,

- Discussion Type
- discussion topicflavours of cobordism cohomology theories -- table
- Category Latest Changes
- Started by Urs
- Comments 17
- Last comment by Urs
- Last Active Mar 16th 2023

- Discussion Type
- discussion topic2-representation
- Category Latest Changes
- Started by David_Corfield
- Comments 2
- Last comment by Urs
- Last Active Mar 16th 2023

Added a reference

- Zhen Huan,
*2-Representations of Lie 2-groups and 2-Vector Bundles*(arXiv:2208.10042)

- Zhen Huan,

- Discussion Type
- discussion topicstringor bundle
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 16th 2023

- Discussion Type
- discussion topicWhat is an elliptic object?
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Mar 16th 2023

- Discussion Type
- discussion topichomotopical algebraic quantum field theory
- Category Latest Changes
- Started by Urs
- Comments 18
- Last comment by Urs
- Last Active Mar 16th 2023

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 topicIntroduction to Topology -- 2
- Category Latest Changes
- Started by nLab edit announcer
- Comments 9
- Last comment by nLab edit announcer
- Last Active Mar 16th 2023

- Discussion Type
- discussion topicconcept with an attitude
- Category Latest Changes
- Started by Urs
- Comments 21
- Last comment by Urs
- Last Active Mar 16th 2023

This is maybe mainly for entertainment. But don’t forget that for newcomers there is a real issue here which may well be worth explaining:

In mathematics it happens at times that one and the same concept is given two different names to indicate a specific perspective, a certain attitude as to what to do whith such objects.

Here are examples:

A

*quiver*is just a directed graph (pseudograph, to be explicit). But one says*quiver*instead of*directed graph*when one is interested in studying*quiver representations*: functors from the free category on that graph to the category of finite-dimensional vector spaces.A

*presheaf*is just a contravariant functor. But one says*presheaf*instead of*contravariant functor*when one is interested in studying its sheafification, or even if one is just intersted in regarding the category of functors with its structure of a topos: the presheaf topos.

(…)

- Discussion Type
- discussion topicMee Seong Im
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 16th 2023

- Discussion Type
- discussion topicnondeterministic automaton
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 16th 2023

added the following pointers on non-deterministic automata as 1-dimensional defect TQFTs:

Paul Gustafson, Mee Seong Im, Remy Kaldawy, Mikhail Khovanov, Zachary Lihn,

*Automata and one-dimensional TQFTs with defects*[arXiv:2301.00700]Mee Seong Im,

*Correspondence between automata and one-dimensional Boolean topological theories and TQFTs*, talk at*QFT and Cobordism*, CQTS (Mar 2023) [web]

In the course of doing so I tried to fix some oddities in this neglected entry. But I don’t have time to do it justice.

- Discussion Type
- discussion topicmonad (in computer science)
- Category Latest Changes
- Started by Urs
- Comments 24
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicKleisli triple
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicNathan Geer
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicsuper Chern-Simons theory
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topichigher category theory
- Category Latest Changes
- Started by Urs
- Comments 13
- Last comment by Christoph Dorn
- Last Active Mar 15th 2023

started to (re)structure the entry higher category theory roughly along the lines of the new structure at category theory. But for the moment many sections just contain link lists.

- Discussion Type
- discussion topictopological quantum computation with anyons -- references
- Category Latest Changes
- Started by Urs
- Comments 31
- Last comment by Urs
- Last Active Mar 15th 2023

I am giving this bare list of references its own entry, so that it may be

`!include`

-ed into related entries (such as*topological quantum computation*,*anyon*and*Chern-Simons theory*but maybe also elsewhere) for ease of updating and synchronizing

- Discussion Type
- discussion topicquantum topology
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicquantum computation
- Category Latest Changes
- Started by Urs
- Comments 29
- Last comment by Urs
- Last Active Mar 15th 2023

stub for

*quantum computation*

- Discussion Type
- discussion topicassociative n-category
- Category Latest Changes
- Started by jamievicary
- Comments 9
- Last comment by Christoph Dorn
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicRozansky-Witten theory
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicYoneda extension
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicunknot
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Mar 15th 2023

added this pointer on the universal Vassiliev invariant of the unknot:

- Dror Bar-Natan, Stavros Garoufalidis, Lev Rozansky, Dylan Thurston,
*Wheels, wheeling, and the Kontsevich integral of the unknot*(q-alg/9703025)

- Dror Bar-Natan, Stavros Garoufalidis, Lev Rozansky, Dylan Thurston,

- Discussion Type
- discussion topicLouis-Hadrien Robert
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicshuffle
- Category Latest Changes
- Started by Noam_Zeilberger
- Comments 6
- Last comment by nLab edit announcer
- Last Active Mar 15th 2023

- Discussion Type
- discussion topicepi-pullback
- Category Latest Changes
- Started by nLab edit announcer
- Comments 5
- Last comment by varkor
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicmonoidal monad
- Category Latest Changes
- Started by Todd_Trimble
- Comments 15
- Last comment by Urs
- Last Active Mar 14th 2023

Started an article on monoidal monad. An earlier redirect had sent it over to Hopf monad which is something that Zoran was working on, but I think it deserves an article to itself, with discussion of the relation to commutative monads, etc. (which I have started).

- Discussion Type
- discussion topicUlrich Bunke
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Mar 14th 2023

On (topological) inertia stacks

- Ulrich Bunke, Markus Spitzweck, Thomas Schick,
*Inertia and delocalized twisted cohomology*, Homotopy, Homology and Applications 10(1) 129–180 (2008)math.KT/0609576

doi

- Ulrich Bunke, Markus Spitzweck, Thomas Schick,

- Discussion Type
- discussion topicinertia orbifold
- Category Latest Changes
- Started by Urs
- Comments 14
- Last comment by zskoda
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicGabriel–Ulmer duality
- Category Latest Changes
- Started by nLab edit announcer
- Comments 8
- Last comment by varkor
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicBPS state
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by zskoda
- Last Active Mar 14th 2023

I have added to

*BPS state*and to*wall crossing*pointers to two introductory lecture notes

- Discussion Type
- discussion topicMarkus Reineke
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicstratified space
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Christoph Dorn
- Last Active Mar 14th 2023

I have created

*stratified space*in order to collect some references

- Discussion Type
- discussion topicmanifold diagram
- Category Latest Changes
- Started by Christoph Dorn
- Comments 4
- Last comment by Christoph Dorn
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicgeometric computad
- Category Latest Changes
- Started by Christoph Dorn
- Comments 3
- Last comment by Christoph Dorn
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicproper action
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by nLab edit announcer
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicPiotr Sułkowski
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicPiotr Kucharski
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicknots-quivers correspondence
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicgeneric representation theory
- Category Latest Changes
- Started by J-B Vienney
- Comments 4
- Last comment by Urs
- Last Active Mar 14th 2023

- Discussion Type
- discussion topicmaximal compact subgroup
- Category Latest Changes
- Started by Urs
- Comments 20
- Last comment by Dmitri Pavlov
- Last Active Mar 14th 2023

I have tried to start a table at

*maximal compact subgroup*listing Lie groups and their max compact subgroups. But once again the table does not want to typeset properly.Have to run now, will try to fiddle with this later.

- Discussion Type
- discussion topiclist of journals publishing homotopy theory and category theory
- Category Latest Changes
- Started by Mike Shulman
- Comments 53
- Last comment by varkor
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicimmanant
- Category Latest Changes
- Started by J-B Vienney
- Comments 1
- Last comment by J-B Vienney
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicpermanent
- Category Latest Changes
- Started by J-B Vienney
- Comments 1
- Last comment by J-B Vienney
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicNicholas Kuhn
- Category Latest Changes
- Started by J-B Vienney
- Comments 1
- Last comment by J-B Vienney
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicenriched bicategory
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by varkor
- Last Active Mar 13th 2023

have created enriched bicategory in order to help Alex find the appropriate page for his notes.

- Discussion Type
- discussion topicComptes rendus hebdomadaires des séances de l'Académie des sciences
- Category Latest Changes
- Started by varkor
- Comments 8
- Last comment by varkor
- Last Active Mar 13th 2023

- Discussion Type
- discussion topiclocally internal category
- Category Latest Changes
- Started by nLab edit announcer
- Comments 8
- Last comment by varkor
- Last Active Mar 13th 2023

- Discussion Type
- discussion topichomotopy limit
- Category Latest Changes
- Started by DavidRoberts
- Comments 4
- Last comment by zskoda
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicstratified homotopy hypothesis
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active Mar 13th 2023

Added Peter Haine article and his claim to have proved the stratified homotopy hypothesis.

- Discussion Type
- discussion topicPeter Haine
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by David_Corfield
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicposet-stratified space
- Category Latest Changes
- Started by Mike Shulman
- Comments 10
- Last comment by David_Corfield
- Last Active Mar 13th 2023

Created poset-stratified space. I wasn’t sure what to call this, since the references generally just call it a “stratified space”, but our page stratified space is about

*all*notions of stratified space rather than just one of them. Suggestions are welcome.(Am now listening to John Francis talk about these things at the Mid-Atlantic Topology Conference.)

- Discussion Type
- discussion topicminimal ideal
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by mattecapu
- Last Active Mar 13th 2023

- Discussion Type
- discussion topicstring topology
- Category Latest Changes
- Started by zskoda
- Comments 24
- Last comment by zskoda
- Last Active Mar 13th 2023

New entry string topology, short sentence and several complete references, with links.

- Discussion Type
- discussion topicMatteo Capucci
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Guest
- Last Active Mar 12th 2023

- Discussion Type
- discussion topicquasi-limit
- Category Latest Changes
- Started by mattecapu
- Comments 6
- Last comment by Urs
- Last Active Mar 12th 2023

- Discussion Type
- discussion topicFredholm operator
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Dmitri Pavlov
- Last Active Mar 12th 2023

I have edited a bit at

*Fredholm operator*. Also started a stubby*Fredholm module*in the process. But it remains very much unfinished. Have to interrupt now for a bit.

- Discussion Type
- discussion topicoperad
- Category Latest Changes
- Started by Todd_Trimble
- Comments 20
- Last comment by Guest
- Last Active Mar 12th 2023

Wrote a section on the associated monad at operad, in terms of the framework introduced under the section titled Preparation.

- Discussion Type
- discussion topicdifferential category
- Category Latest Changes
- Started by Tim_Porter
- Comments 24
- Last comment by J-B Vienney
- Last Active Mar 11th 2023

- Discussion Type
- discussion topicErez Berg
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 11th 2023

- Discussion Type
- discussion topicFrank Pollmann
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Mar 11th 2023