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    • Page created, but author did not leave any comments.

      v1, current

    • a bare minimum, for the moment just as to satisfy links

      v1, current

    • Clarify how few decidable subsets the real line can have and give examples of when this happens.

      diff, v11, current

    • Page created, but author did not leave any comments.

      v1, current

    • I edited lambda-ring, added a definition from the thesis of John R. Hopkins. Later on I will add the definitions of Hazewinkel, too. This entry has a long (and very instructive) idea-section. Maybe I find time to fill in some more details to these ideas.

    • Page created, but author did not leave any comments.

      v1, current

    • Added a reference to a recent paper on the transcendental ideal by Kovač.

      diff, v9, current

    • at books about string theory I have added some paragraphs with descriptions of books in the first section (“Mathematically inclined monographs about string theory”)

    • starting something – not done yet but need to save

      v1, current

    • Removed the reference to Mike Shulman’s blog articles in HoTT since they don’t specifically mention this spectral sequence.

      diff, v10, current

    • Can we think of free cocompletion as a left adjoint? In what follows, by ’cocomplete’ I mean ’having all small colimits’.

      Free cocompletion can’t be a left adjoint functor from CatCat (the category of small categories) to CocompleteCATCocompleteCAT (the category of locally small cocomplete categories), because there’s no right adjoint CocompleteCATCatCocompleteCAT \to Cat.

      Also surely not from CatCat to CocompleteCatCocompleteCat (the category of small cocomplete categories), because there just aren’t enough small cocomplete categories: only posets.

      The article on free cocompletion mentions a free cocompletion functor from CATCAT (the category of locally small categories) to CocompleteCATCocompleteCAT, studied by Day and Lack. There’s an obvious candidate right adjoint from CocompleteCATCocompleteCAT to CATCAT. So this might work!

      Does it?

      Day and Lack work in the enriched case, and I’m a bit confused, but they seem to imply that free cocompletion is a pseudomonad on CATCAT, which would be a step in the right direction.

    • brief category: people-entry for hyperlinking references

      v1, current

    • Page created, but author did not leave any comments.

      v1, current

    • Page created, but author did not leave any comments.

      Anonymous

      v1, current

    • splitting this off from AdS3/CFT2 as an entry just listing references, to be !includeed into the References-lists of other entries

      v1, current

    • starting a category:reference-entry – not done yet (on my phone here…)

      v1, current

    • (created my own page because I have a huge ego)

      v1, current

    • starting something – not done yet but need to save

      v1, current

    • Detection of the 21cm hydrogen absorption line expected in the CMB has been claimed now. Such a detection is thought to have implications for observational cosmology comparable in relevance to those of the recent gravitational wave detection. I have collected some original articles and reviews here in an otherwise empty entry hydrogen line

    • Fixed link to Leonardo Rastelli, Lectures on open/closed string duality

      Anonymous

      diff, v3, current

    • stub entry, for the moment just so as to satisfy links

      v1, current

    • I keep having the need to point to something like mass gap problem. So now I created a stub for it, just so that the links works. Has to be expanded, clearly.

    • created just to satisfy liunks, but I added a minimum of an Idea-section

      v1, current

    • stub, for the moment just so as to satisfy links

      v1, current

    • added a graphics showing length scales of fundamental physics in the observable universe

      diff, v4, current

    • Todd points out elsewhere that there is a problem with the following sentence in the section Smallness in the context of universes:

      CC is essentially UU-small if there is a bijection from its set of morphisms to an element of UU (the same for the set of objects follows); this condition is non-evil.

      (introduced in revision 11).

      It looks to me that first of all this is not the right condition – the right condition must mention equivalence of categories to a U-small category.

      diff, v31, current

    • I came to think that the term geometric type theory for the type theory internal toi sheaf toposes should exists. Thanks to Bas Spitter for pointing out that Steve Vickers had already had the same idea (now linked to at the above entry).

      Also created geometric homotopy type theory in this vein, with some evident comments.

    • This is a base topic of my contribution. It introduces a new function that gives series whose coefficients are powers of fine structure constant. Furthermore each member represents natural physical interaction. It can be treated as natural physics that introduces natural particles.

      May be I made a lot of mistakes. I will correct them.

      v1, current

    • added a further quote from

      interview with Mike Duff by Graham Fermelo, The universe speaks in numbers – Interview 14 (web):

      (7:04) The problem we face is that we have a patchwork understanding of M-theory, like a quilt. We understand this corner and that corner, but what’s lacking is the overarching big picture. So directly or indirectly, my research hopes to explain what M-theory really is. We don’t know what it is.

      In a certain sense, and this is not a popular statement, I think it’s premature to be asking: “What are the empirical consequences”, because it’s not yet in a mature enough state, where we can sensibly make falsifiable prediction.

      diff, v13, current

    • a stub, for the moment just for completeness and to satisfy links

      v1, current