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- Discussion Type
- discussion topictype II supergravity
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Oct 10th 2020

added pointer to

- Igor Bandos, Alexei Nurmagambetov, Dmitri Sorokin,
*Various Faces of Type IIA Supergravity*, Nucl. Phys. B676 (2004) 189-228 (arXiv:hep-th/0307153)

- Igor Bandos, Alexei Nurmagambetov, Dmitri Sorokin,

- Discussion Type
- discussion topicJ-homomorphism
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Urs
- Last Active Oct 9th 2020

added the plain traditional definition to

*J-homomorphism*

- Discussion Type
- discussion topiclinguistics - contents
- Category Latest Changes
- Started by Thomas Holder
- Comments 1
- Last comment by Thomas Holder
- Last Active Oct 9th 2020

- Discussion Type
- discussion topicgeneralized quantifier
- Category Latest Changes
- Started by Thomas Holder
- Comments 4
- Last comment by Urs
- Last Active Oct 9th 2020

I created a new page generalized quantifier mostly to drop some references.

- Discussion Type
- discussion topictranscendental grammar
- Category Latest Changes
- Started by Thomas Holder
- Comments 2
- Last comment by Thomas Holder
- Last Active Oct 8th 2020

- Discussion Type
- discussion topicprojective space
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Hurkyl
- Last Active Oct 8th 2020

started a stub for projective space

- Discussion Type
- discussion topiccategorical model of dependent types
- Category Latest Changes
- Started by Mike Shulman
- Comments 37
- Last comment by Mike Shulman
- Last Active Oct 8th 2020

Created categorical model of dependent types, describing the various different ways to strictify category theory to match type theory and their interrelatedness. I wasn’t sure what to name this page — or even whether it should be part of some other page — but I like having all these closely related structures described in the same place.

- Discussion Type
- discussion topicGrothendieck construction
- Category Latest Changes
- Started by Urs
- Comments 39
- Last comment by Hurkyl
- Last Active Oct 8th 2020

added to Grothendieck construction a section Adjoints to the Grothendieck construction

There I talk about the left adjoint to the Grothendieck construction the way it is traditionally written in the literature, and then make a remark on how one can look at this from a slightly different perspective, which then is the perspective that seamlessly leads over to Lurie's realization of the (oo,1)-Grothendieck construction.

There is a CLAIM there which is maybe not entirely obvious, but straightforward to check. I'll provide the proof later.

- Discussion Type
- discussion topictheory of presheaf type
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Thomas Holder
- Last Active Oct 8th 2020

- Discussion Type
- discussion topicpartial evaluation
- Category Latest Changes
- Started by PaoloPerrone
- Comments 4
- Last comment by atmacen
- Last Active Oct 8th 2020

- Discussion Type
- discussion topicétale homotopy
- Category Latest Changes
- Started by Urs
- Comments 26
- Last comment by Urs
- Last Active Oct 8th 2020

I made

*étale homotopy*and*étale homotopy theory*be redirects to the entry geometric homotopy groups in an (infinity,1)-topos

- Discussion Type
- discussion topicbar construction
- Category Latest Changes
- Started by Urs
- Comments 12
- Last comment by nLab edit announcer
- Last Active Oct 7th 2020

the standard

*bar complex*of a bimodule in homological algebra is a special case of the bar construction of an algebra over a monad. I have added that as an example to bar construction.I also added the crucial remark (taken from Ginzburg’s lecture notes) that this is where the term “bar” originates from in the first place: the original authors used to write the elements in the bar complex using a notaiton with lots of vertical bars (!).

(That’s a bad undescriptive choice of terminoiogy. But still not as bad as calling something a “triple”. So we have no reason to complain. ;-)

- Discussion Type
- discussion topicKünneth theorem
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by nLab edit announcer
- Last Active Oct 7th 2020

at

*Künneth theorem*I have spelled out statemennt and detailed proof of the Künneth theorem in ordinary homology.

- Discussion Type
- discussion topicpoint of a topos
- Category Latest Changes
- Started by Urs
- Comments 25
- Last comment by Thomas Holder
- Last Active Oct 7th 2020

commented in the discussion at point of a topos and have a question there.

- Discussion Type
- discussion topicspinning particle
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Oct 7th 2020

added pointer to today’s

- Krzysztof Andrzejewski, Cezary Gonera, Joanna Goner, Piotr Kosinski, Pawel Maslanka,
*Spinning particles, coadjoint orbits and Hamiltonian formalism*(arXiv:2008.09478)

- Krzysztof Andrzejewski, Cezary Gonera, Joanna Goner, Piotr Kosinski, Pawel Maslanka,

- Discussion Type
- discussion topicgravitational wave
- Category Latest Changes
- Started by Urs
- Comments 15
- Last comment by Urs
- Last Active Oct 7th 2020

just to make links work, I have started a minimum at

*gravitational wave*.

- Discussion Type
- discussion topicworldline formalism
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active Oct 6th 2020

created

*worldline formalism*to go with this Physics.SE answer

- Discussion Type
- discussion topicdisjoint coproduct
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Sam Staton
- Last Active Oct 5th 2020

I have expanded various sections at

*disjoint coproduct*. In particular towards the end is now a mentioning of the fact that in a positive category morphisms into a disjoint coproduct are given by factoring disjoint summands of the domain through the canonical inclusions.Also,I made

*positive category*and variants redirect to extensive category.

- Discussion Type
- discussion topicuniverse in a topos
- Category Latest Changes
- Started by Thomas Holder
- Comments 1
- Last comment by Thomas Holder
- Last Active Oct 5th 2020

- Discussion Type
- discussion topicHopf-Wess-Zumino term
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Oct 5th 2020

- Discussion Type
- discussion topicequivariant Chern-Dold character
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Oct 4th 2020

- Discussion Type
- discussion topicChern-Dold character
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 4th 2020

finally splitting this off from

*Chern character*

- Discussion Type
- discussion topicChern character
- Category Latest Changes
- Started by Urs
- Comments 43
- Last comment by Urs
- Last Active Oct 4th 2020

stub for Chern character

just the blind definition so far, to be expanded later

- Discussion Type
- discussion topicequivariant K-theory
- Category Latest Changes
- Started by Urs
- Comments 15
- Last comment by Urs
- Last Active Oct 4th 2020

added to

*equivariant K-theory*comments on the relation to the operator K-theory of crossed product algebras and to the ordinary K-theory of homotopy quotient spaces (Borel constructions). Also added a bunch of references.(Also finally added references to Green and Julg at

*Green-Julg theorem*).This all deserves to be prettified further, but I have to quit now.

- Discussion Type
- discussion topicBob Oliver
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 4th 2020

brief

`category:people`

-entry for hyperlinking references at*equivariant Chern character*

- Discussion Type
- discussion topicGray tensor product
- Category Latest Changes
- Started by Thomas Holder
- Comments 1
- Last comment by Thomas Holder
- Last Active Oct 4th 2020

- Discussion Type
- discussion topicequivariant rationalization
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 3rd 2020

- Discussion Type
- discussion topicclassifying topos
- Category Latest Changes
- Started by Urs
- Comments 53
- Last comment by Thomas Holder
- Last Active Oct 2nd 2020

edited classifying topos and added three bits to it. They are each marked with a comment "check the following".

This is in reaction to a discussion Mike and I are having with Richard Williamson by email.

- Discussion Type
- discussion topictheory of categories
- Category Latest Changes
- Started by Thomas Holder
- Comments 3
- Last comment by Thomas Holder
- Last Active Oct 2nd 2020

- Discussion Type
- discussion topicexponentiable topos
- Category Latest Changes
- Started by Thomas Holder
- Comments 5
- Last comment by Thomas Holder
- Last Active Oct 2nd 2020