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Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

• brief category:people-entry for hyperlinking references

• Gave this entry a minimum of an Idea-section and started adding as list of examples

• null edit to start discussion page

Anonymous

• Correct the characterization of nerves of groupoids.

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• starting something. Nothing to be seen yet here, but I need to save now to have the link.

• brief category:people-entry for hyperlinking references at non-abelian T-duality and elsewhere

• brief category:people-entry for hyperlinking references

• Trivial edit to create a discussion page.

• I added some material to Peano arithmetic and Robinson arithmetic. At the latter, I replaced the word “fragment” (which sounds off to my ears – actually Wikipedia talks about thisterm a little) with “weakening”.

Still some links to be inserted.

• Added to Dedekind cut a short remark on the $\neg\neg$-stability of membership in the lower resp. the upper set of a Dedekind cut.

• starting something

• brief category:people-entry for hyperlinking references

• starting something – remains a stub for the moment, to be continued

• I have added references to two (overlapping) papers which list elementary examples of factorization systems associated with the notions of: compact, discrete, connected, and totally disconnected spaces, dense image, induced topology, and separation axioms; finite groups being nilpotent, solvable, torsion-free, p-groups, and prime-to-p groups; injective and projective modules; injective, surjective, and split homomorphisms.

Anonymous

• Added a reference to the 2023 Bourke paper An orthogonal approach to algebraic weak factorisation systems.

• I have added to orthogonal factorization system

1. in the Definition-section three equivalent explicit formulations of the definition;

2. in the Properties-section the statement of the cancellability property.

Wanted to add more (and to add the proofs). But have to quit now. Maybe later.

• I have been polishing and expanding the entry weak factorization system:

• gave it an Idea-section;

• gave the definitions numbered environments and full details;

• spelled out the proof of the closure properties in full detail.

Regarding notation: I decided to use as generic name for a weak factorization system:

• not $(L,R)$, as used to be used in the entry (for that’s already my preferred generic choice for pairs of adjoint functors on the $n$Lab, and for discussion of Quillen adjunctions the notation conventions would clash);

• not $(E,M)$ or the like, since that gives no hint as to what is meant (running into an “$E$” in the middle of some discussion, the reader is always at risk of having to browse back to figure out which class is meant);

• but… $(Proj, Inj)$, for that is nicely indicating what is meant.

• brief category:people-entry for hyperlinking references

• I started reworking a quasi-periodic study of mine on propositions as types that introduces the factors of "proof hints" and "untyped terms" into the analogy.

Update $(\forall~\mathfrak{Hallows'}~\mathfrak{Eve}^\mathfrak{2}, \mathfrak{2009})$. This material is now at propositions as types in combinatory algebra.

• After discussion here I have changed the organization of the entry structure and then expanded a bit by adding an Idea-section and a bit more here and there.

(The previous organization of the entry instead made it look like structure in model theory is a concept on par with that discussed at stuff, structure, property. But instead, the latter axiomatizes the general notion of “structure on something” as such, whereas the former is an example of a structure on something (namely an “$L$-structure on a set”). The new version aims to reflect this properly.)

• a category:reference-entry

• Started the page. First question: is homotopy theory a part of algebraic topology?

Patrick Nicodemus

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• brief category:people-entry for hyperlinking references

• Pi Calculus

Ammar Husain

Anonymous

Anon

• Included the condition on sequential (co)limits that the indexing ordinal should be nonzero, which I presume to be the correct convention. (e.g. based on the description they are a special case of filtered colimits)

• Just mentioned the idea. Will complete later.

• Page created. Will add more later.

• created the page for Mealy morphisms and just put in one reference

Tim Hosgood

• Corrected a link. Before the word “derivation” linked to the page for derivations in differential algebra.

Sam Winnick

• I keep feeling the need to point to an entry named formal logic. None of the existing entries seems to quite deserve to be where this link should be redirecting to. So I created a page formal logic with just some pointers to pages that the reader might expect behind this term.

Just so that I can use that link for the time being.