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- Discussion Type
- discussion topicgeometric surjection/embedding factorization
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active May 18th 2011

have split off geometric surjection/embedding factorization from the relevant entries. Maybe I find the time to spell out the proof there.

- Discussion Type
- discussion topicB-bordism
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 16th 2011

stub for B-bordism – just to record the Manifold Atlas-reference for the moment

- Discussion Type
- discussion topicdifferential orientation
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by zskoda
- Last Active May 15th 2011

stub for differential orientation

- Discussion Type
- discussion topicfundamental class
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 13th 2011

stub for fundamental class

- Discussion Type
- discussion topicworldvolume, target space, background gauge field
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 13th 2011

As supplementary entries for sigme model I have created

- Discussion Type
- discussion topicdefining ideal of a topologizing subcategory
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active May 12th 2011

New entry defining ideal of topologizing subcategory (of an abelian category), wanted at conormal bundle. It is in fact a subfunctor of the identity functor and if we evaluate it on projective generator in the case of a module category then we get the usual ideal in the corresponding ring.

- Discussion Type
- discussion topicgeometric transformation
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 11th 2011

created geometric transformation, just for completeness.

- Discussion Type
- discussion topicdifferential function complex
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active May 11th 2011

split of differential function complex from differential cohomology and starzed expanding it. But not done yet.

- Discussion Type
- discussion topicThree Roles of Quantum Field Theory
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active May 10th 2011

created reference-entry Three Roles of Quantum Field Theory

- Discussion Type
- discussion topicMorita morphism
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by DavidRoberts
- Last Active May 9th 2011

since I needed the link to exist, I have created a stub for Morita morphism (of Lie groupoid)s. Made Hilsum-Skandalis morphism redirect to it, for the moment.

- Discussion Type
- discussion topicD-affinity
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active May 8th 2011

Affinity in the context of D-modules, as defined by Alexander Beilinson is the subject of a new stub D-affinity. There is a categorical generalization in the MPI1996-53 preprint (pdf) of Lunts and Rosenberg in terms of differential monads. Many generalizations of Beilinson-Bernstein localization theorem have their intuitive explanation in a two-step reasoning. First the noncommutative algebra in question is understood as a noncommutative (or maybe categorical) resolution of singularities of a commutative object. Then the latter satisfies D-affinity and one can localize.

- Discussion Type
- discussion topicdomain globalization
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active May 8th 2011

New entry domain globalization of functors (zoranskoda) under development. The codomain globalization is more trivial. This are questions of extending the constructions related to Beck’s comonadicity from categories to functors. Our interest with Gabi Bohm are mainly for covers by localizations with some equivariance/compatibility with respect to additional (co)monad, which are a matter of ongoing work. This compatibility is like, or some dual of the one in the definition of morphisms of Q-categories and also the compatibility of differential monads and localization, studied by Lunts and Rosenberg. The latter is related to the classical fact that the assignment of ring of regular differential operators to a commutative ring $R\mapsto Diff(R)$ is compatible with exact localizations, in the sense that $S^{-1}R \mapsto S^{-1}Diff(R)$; and also to Beilinson’s notion of D-affinity.

- Discussion Type
- discussion topicNoether's theorem
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Eric
- Last Active May 8th 2011

created Noether’s theorem – no-nonsense version

- Discussion Type
- discussion topic(n,r)-logic
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 7th 2011

I have created stubs for the missing entries to complete this table:

The main actual content I added are, (at 2-type theory and 2-logic): pointers to Dan Licata’s thesis and to Mike’s personal wiki pages.

I’d hope that one outcome of the present $n$Café discussion is that eventually some of these entries get equipped with some useful content.

(P.S. I would have linked to material by Mike Stay, too, but I don’t know what to link to.)

- Discussion Type
- discussion topiclocally algebra-ed topos
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Mike Shulman
- Last Active May 7th 2011

I am about to create an entry called locally algebra-ed topos in the spirit of the section for local algebras at classifying topos.

I tend to think this terminology is better than the undescriptive “structured topos”, but please let me know what you think.

I would like to amplify the following fact:

if we agree to say (which is reasonable) that

an

*algebra*is a model of some essentially algebraic theory, hence a lex functor out of a finite-limite category;a

*local algebra*with respect to a coverage on the category is such a lex functor that preserves covers.

then the statement is:

- geometric theories are equivalently theories of local algebras.

- Discussion Type
- discussion topicvariational caclulus - contents
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 6th 2011

I have started a new subject complex variational calculus - contents and have included it as a floating TOC into relevant entries

- Discussion Type
- discussion topiccharge
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 6th 2011

stub for charge

- Discussion Type
- discussion topicdifferential monad
- Category Latest Changes
- Started by zskoda
- Comments 3
- Last comment by zskoda
- Last Active May 6th 2011

I started an important entry differential monad. According to Lunts-Rosenberg MPI 1996-53 pdf differential calculus on schemes and noncommutative schemes can be derived from the yoga of coreflective topologizing subcategories in the abelian category of quasicoherent sheaves on the scheme, like the $\mathbb{T}$-filtration, and $\mathbb{T}$-part, in the case when the topologizing subcategory is the diagonal in the sense of the smallest subcategory of the category of additive endofunctors having right adjoint which contains the identity functor – in that case we say differential filtration and differential part. The regular differential operators are the elements of the differential part of the bimodule of endomorphisms. Similarly, one can define the conormal bundle etc.

- Discussion Type
- discussion topic[[cartesian category]]
- Category Latest Changes
- Started by TobyBartels
- Comments 4
- Last comment by SridharRamesh
- Last Active May 6th 2011

I’ve disambiguated links to cartesian category. I suggest that we avoid this term.

- Discussion Type
- discussion topiccoherent (oo,1)-operad
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active May 5th 2011

stub for coherent (infinity,1)-operad

- Discussion Type
- discussion topicnew entries
- Category Latest Changes
- Started by Tim_Porter
- Comments 1
- Last comment by Tim_Porter
- Last Active May 4th 2011

Created a stubby entry for Gereon Quick, and added some more into (or fixed typos on) Daniel Isaksen, Cech homotopy,profinite homotopy theory and pro-homotopy theory.

- Discussion Type
- discussion topicJon Pridham
- Category Latest Changes
- Started by Tim_Porter
- Comments 1
- Last comment by Tim_Porter
- Last Active May 4th 2011

I created an entry for Jonathan Pridham.

- Discussion Type
- discussion topicO-monoidal (oo,1)-category
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active May 3rd 2011

have added to monoidal (infinity,1)-category the definition of $\mathcal{O}$-monoidal $(\infty,1)$-category, for $\mathcal{O}$ an $\infty$-operad

(though maybe this definition either deserves its own entry or ought to be included instead at symmetric monoidal (infnity,1)-category)

- Discussion Type
- discussion topiccategory of factorizations
- Category Latest Changes
- Started by Tim_Porter
- Comments 4
- Last comment by Tim_Porter
- Last Active May 1st 2011

A point of information. These constructions are due to Charles Wells in this particular setting and to Jonathan Leech, (H-coextensions of monoids, vol. 1, Mem. Amer. Math. Soc, no. 157, American Mathematical Society, 1975) in the single object case, and McLane introduces the category of factorisations I think. Charlie Wells even pushes things a bit further than Baues. Hans does not seem to have known of that work. (Charles Wells, Extension theories for categories (preliminary report), (available from http://www.cwru.edu/artsci/math/wells/pub/pdf/catext.pdf), 1979. ) I have been meaning to have a go at this entry as I have written up a modern version of Wells especially in the non-Abelian case. There is a very nice interpretation of Natural System as a lax functor. (I will do this some time…. but I can make the notes available to anyone interested.)

- Discussion Type
- discussion topiccharacteristic class of a structure
- Category Latest Changes
- Started by zskoda
- Comments 5
- Last comment by Urs
- Last Active May 1st 2011

New entry characteristic class of a structure to complement characteristic class and historical note on characteristic classes. I did not link to it from outside so far.

- Discussion Type
- discussion topicuniversally closed morphism
- Category Latest Changes
- Started by zskoda
- Comments 4
- Last comment by Urs
- Last Active Apr 30th 2011

universally closed morphism and improvements at proper morphism

- Discussion Type
- discussion topicproadjoint
- Category Latest Changes
- Started by zskoda
- Comments 2
- Last comment by Tim_Porter
- Last Active Apr 30th 2011

New entry proadjoint.

- Discussion Type
- discussion topicnuclear space
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Apr 30th 2011

New stub nuclear topological vector space with redirect nuclear space. Grothendieck’s reference also at Fredholm operator.

- Discussion Type
- discussion topicFréchet
- Category Latest Changes
- Started by TobyBartels
- Comments 6
- Last comment by Andrew Stacey
- Last Active Apr 28th 2011

Urs created Frechet manifold, so I created Frechet space. (We violated the naming conventions too, but I guess it's OK since we have the redirects in.)

- Discussion Type
- discussion topictoposes as theories
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by zskoda
- Last Active Apr 28th 2011

I am trying to begin to coherently add some of the topics of part D of the Elephant into the Lab.

Currently I am creating lots of stub entries, splitting them off from existing entries if necessary, cross-link them appropriately, and then eventually add content to them.

so far I have for instance created new (mostly stub) entries for things like

I have created

and made it a disambiguation page.

I have edited the linked table of contents at Elephant, etc.

(or rather I will have in a few minutes. All my save-windows are currently stalled. Will have to restart the server.)

- Discussion Type
- discussion topicrepresentable fibered category
- Category Latest Changes
- Started by zskoda
- Comments 6
- Last comment by Urs
- Last Active Apr 27th 2011

New entry representable fibered category.

- Discussion Type
- discussion topicstandard site
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 27th 2011

created standard site (maybe not a great term, but since I am $n$Labifying the Elephant). Added the theorem that every sheaf topos has a standard site of definition to site

- Discussion Type
- discussion topicZariski site
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 27th 2011

have created Zariski site

- Discussion Type
- discussion topicslice category
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active Apr 27th 2011

added to overcategory the statement about lifs to adjunctions to slices, here

- Discussion Type
- discussion topicsyntactic site
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Apr 27th 2011

a bit of content at syntactic site

- Discussion Type
- discussion topicindexed topos
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 26th 2011

started indexed topos

- Discussion Type
- discussion topicbase topos
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 26th 2011

I have touched indexed category and then started filling some first content into base topos.

- Discussion Type
- discussion topiccartesian, regular, coherent, geometric
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 26th 2011

I have created the following web of entries

cartesian category, cartesian functor, cartesian logic, cartesian theory

regular category, regular functor, regular logic, regular theory, regular coverage, regular topos

coherent category, coherent functor, coherent logic, coherent theory, coherent coverage, coherent topos

geometric category, geometric functor, geometric logic, geometric theory

Most of them stubs. Partly just material split off from other entries. But all with the relavent pointers to the Elephant or other literature. To be expanded.

- Discussion Type
- discussion topicHodge to de Rham spectral sequence degeneration
- Category Latest Changes
- Started by zskoda
- Comments 3
- Last comment by Andrew Stacey
- Last Active Apr 26th 2011

I have created degeneration conjecture required at Dmitri Kaledin. In my memory, I never heard ofthis

**degeneration conjecture**by precisely*that*name and I do not like it (there are so many degeneration conjectures in other fields, some of which I heard under*that*name). It is usually said the**degeneration of Hodge to de Rham spectral sequence**(conjecture). It has a classical analogue. I put redirect degeneration of Hodge to de Rham spectral sequence.

- Discussion Type
- discussion topicdifferential cohomology in an (∞,1)-topos -- survey
- Category Latest Changes
- Started by David_Corfield
- Comments 18
- Last comment by Urs
- Last Active Apr 25th 2011

In differential cohomology in an (∞,1)-topos – survey, I can’t guess what ’nothing’ should be here:

The curvature characteristic forms / Chern characters in the traditional formulation of differential cohomology take values in abelian $\infty$-Lie algebras and are therefore effectively nothing differential forms with values in a complex of vector spaces

- Discussion Type
- discussion topiccartesian morphism
- Category Latest Changes
- Started by zskoda
- Comments 3
- Last comment by Urs
- Last Active Apr 21st 2011

This is an excerpt I wrote at logical functor:

As far as cartesian morphism there are two different universal properties in the literature, which are equivalent for Grothendieck fibered categories but not in general. In what Urs calls the “traditional definition” (but is in fact a later one) one has for every $x'$, for every $h$, for every $g$ such that … there exist a unique da da da. This way it is spelled in Vistoli’s lectures. This is in fact the strongly cartesian property, stronger than one in Gabriel-Grothendieck SGA I.6. The usual, Grothendieck, or weak property takes for $g$ the identity, and the unique lift is of the identity at $p(x_1)$. Then a Grothendieck fibered category is the one which has cartesian lifts for all morphisms below and all targets, and cartesian morphisms are closed under composition. With the strong cartesian property one does not need to require the closedness under composition. Now a theorem says that in a Grothendieck fibered category, a morphism is strongly cartesian iff it is cartesian.

Now I have made some changes to cartesian morphism, so that the entry is aware of the two variants of the universal property, which are not equivalent in general but are equivalent for Grothendieck fibered categories.

There was also a statement there

In words: for all commuting triangles in Y and all lifts through p of its 2-horn to X, there is a unique refinement to a lift of the entire commuting triangle.

which is too vague and I am not happy with, as it does not involve the essential parameter: the morphism for which we test cartesianess. I made a hack to it, and still it is not something I happy with (I like the idea of

*horn*mentioned, however not the lack of appropriate quantifiers/conditions etc.). It is cumbersome to talk horn. (Maybe we could skip the whole statement in this imprecise form, and just mention*please note the filling of the horn in $X$ with prescribed projection in $Y$*or alike). Here is the temporary hack:In imprecise words: for all commuting triangles in $Y$ (involving $p(f)$ as above) and all lifts through $p$ of its 2-horn to $X$ (involving $f$ as above), there is a unique refinement to a lift of the entire commuting triangle.

- Discussion Type
- discussion topicThe Cauchy Problem in Classical Supergravity
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 21st 2011

started a reference-entry The Cauchy Problem in Classical Supergravity, but please don’t look at it before I have polished it tomorrow, when I am more awake.

Also created a stub for super-groupoid in the process. Same comment applies to that.

- Discussion Type
- discussion topicprojection
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by zskoda
- Last Active Apr 20th 2011

I have started a puny disambiguation page projection

- Discussion Type
- discussion topicgauge boson
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 19th 2011

stub for gauge boson

- Discussion Type
- discussion topicphoton
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 19th 2011

stub for photon

- Discussion Type
- discussion topicgluon
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 19th 2011

stub for gluon

- Discussion Type
- discussion topicgaugino
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 19th 2011

stub for gaugino

- Discussion Type
- discussion topicconnection on a double category
- Category Latest Changes
- Started by FinnLawler
- Comments 1
- Last comment by FinnLawler
- Last Active Apr 18th 2011

Stubby little page for connection on a double category.

- Discussion Type
- discussion topicadjoint n-tuple
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Urs
- Last Active Apr 14th 2011

Zoran has created adjoint triple, I have added adjoint quadruple

- Discussion Type
- discussion topicformally unramified morphism
- Category Latest Changes
- Started by Urs
- Comments 12
- Last comment by Urs
- Last Active Apr 14th 2011

I have split off formally unramified morphism from unramified morphism. Then I added the general-abstract topos theoretic characterization, by essentially copy-and-pasting the discussion from formally smooth morphism (and replacing epimorphisms by monomorphisms)

- Discussion Type
- discussion topicformal groupoid
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 13th 2011

stub for formal groupoid. Just collecting references so far.

- Discussion Type
- discussion topicQ-categories (and cohesive toposes)
- Category Latest Changes
- Started by Urs
- Comments 17
- Last comment by zskoda
- Last Active Apr 13th 2011

After Zoran had emphasized it for years without me ever really looking into it, now I have finally read the beginning of Kontsevich-Rosenberg’s article on “Q-categories” in more details… and was struck:

their notion of “generalized sheaves” is essentially nothing but the kind of condition that Lawvere considered in cohesive toposes $(u_! \dashv u^* \dashv u_* \dashv u^!) : T \to S$. More precisely, Lawvere considered the objects $x$ for which the canonical morphism $u_* x \to u_! x$ is an isomorphism. What Kontsevich-Rosenberg call generalized sheaves are those objects for which the

*other*canonical morphism is an isomorphism: $u^* x \to u^! x$.There are mainly two kinds of applications in Kontsevich-Rosenberg:

the original one was to find the right notion of sheaves over formal duals of non-commutative algebras. Apparently Rosenberg is fond of the insight that for a suitable cohesive presheaf topos (my words of course) the right condition is that $u^* x \to u^! x$ is an iso.

Apparently (if I remember correctly what Zoran told me) Kontsevich added the observation that formal smoothness and hence infinitesimal thickening is naturally described in this context. Now that I looked through it, I realize that what they talk about in this context is really pretty much exactly what I axiomatized as infinitesimal cohesion.

So I am happy: at once now the entire 79 page article by Kontsevich-Rosenberg turns out to be a great resource of examples and applications of cohesive topos technology! Notably they shed more light on the role of those infamous

*extra axioms*that involve the two canoical natural transformations that come with any cohesive topos.For that reason I have now begun expanding the $n$Lab entry Q-category that Zoran once started

- Discussion Type
- discussion topictopologizing subcategory
- Category Latest Changes
- Started by zskoda
- Comments 3
- Last comment by zskoda
- Last Active Apr 13th 2011

This was the query in topologizing subcategory which I summarized shortly:

Mike: Where does the word ’topologizing’ come from?

Zoran Skoda: I am not completely sure anymore, but I think it is from ring theory, where people looked at the localizations at topologizing categories. There exist some topologies on various sets of ideals like Jacobson topology, so it is something of that sort in the language of subcategories instead of the language of filters of ideals. I’ll consult old references like Popescu, maybe I recall better. In any case it is pretty standard and has long history in usage: both classical and modern. No, it is not in Popescu…old related term is in fact talking about topologizing filters of ideals in a ring, so that must be the source…for example, the classical algebra by Faith, vol I, page 520 defines when the set of right ideals is topologizing. I am not good with that notion, but I can make an entry with quotation to be improved later.

- Discussion Type
- discussion topicseparable functor, S-category
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Apr 13th 2011

New microstubs S-category, separable coring and finally some substantial material at separable functor at last. The monograph by Caenapeel, Militaru and Zhu listed at separable functor studies Frobenius functors and separable functors in parallel; there are relations in a number of interesting situations. Frobenius functors are those where left and right adjoint are the same (hence in particular we have adjoint n-tuple for every $n$). Separable is a notion which is about certain spliting condition. This spliting is of the kind as spliting in Galois theory, I mean the Grothendieck’s version of classical Galois theory involves separable algebras at one side of Galois equivalence.

S-category due Tomasz Brzeziński is a formalism something similar to Q-categories of Alexander Rosenberg. Tomasz studies formal smoothness and separability in the setup of abelian categories, motivated by corings, Hopf algebras and similar applications. I would guess that understanding those could be useful into better understanding the Galois theory in cohesive topos, but I do not know.

I also created Maschke’s theorem which is one of the motivations for separable functors.

- Discussion Type
- discussion topicformally smooth morphism
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 12th 2011

I have expanded the entry formally smooth morphism:

I have first of all added the general-abstract formalization by Kontsevich-Rosenberg, taking the liberty of polishing it a bit from Q-category language to genuine (cohesive) topos-theoretic language and making contact with the notion of infinitesimal cohesion .

Then I added their theorems about how the general abstract topos-theoretic definitions do reproduce the traditional explicit notions.

Except for one clause : in prop. 5.8.1 of

*Noncommutative spaces*they show that the correct notion of formal smoothness for morphisms is reproduced in the non-commutative case (via the relative Cuntz-Quillen condition). But for the commutative case I see the corresponding statement only for objects (in section 4.1) not for morphisms.Zoran, do you know if they also discuss the relative version in the commutative case? Maybe it’s trivial, I haven’t thought it through yet.

- Discussion Type
- discussion topicMore knot theory stuff
- Category Latest Changes
- Started by Andrew Stacey
- Comments 4
- Last comment by Andrew Stacey
- Last Active Apr 11th 2011

Expanded Vassiliev invariant, started Kontsevich integral, did a bit of reorganisation on knot theory (in particular, linking to more pages).

In case anyone’s wondering, there was a book put on the arXiv a couple of days ago touting itself as an introduction to Vassiliev invariants. I’m reading through it and taking notes as I go. I left in a bit of a rush today so the formatting of the Kontsevich integral went a bit haywire, and I made a statement on the Vassiliev invariant page that I know I didn’t say quite right.

In the arXiv book, Vassiliev invariants are introduced first using the Vassiliev skein relations, not their “proper” way (which I haven’t gotten to yet so I don’t know it). The formula looked very like a boundary map on a complex, but I think it has to be a cubical complex rather than a simplicial one. Only it isn’t the full boundary map, rather a partial boundary map (going to opposite faces), but I didn’t get it straight in my head until later. But now I think I’m going to wait until I read the bit about the

*true*definition - which I guess will be something like this - before correcting it (unless anyone gets there before me, of course).Drew a few more SVGs relevant for knots as well. The code for producing the trefoil knot is very nice now, though I say so myself!

- Discussion Type
- discussion topicPaolo Salvatore
- Category Latest Changes
- Started by Tim_Porter
- Comments 1
- Last comment by Tim_Porter
- Last Active Apr 10th 2011

Stub for Paolo Salvatore.

- Discussion Type
- discussion topicframed little disk operad
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Urs
- Last Active Apr 10th 2011

created framed little disk operad

- Discussion Type
- discussion topicGiansiracusa
- Category Latest Changes
- Started by Tim_Porter
- Comments 1
- Last comment by Tim_Porter
- Last Active Apr 9th 2011

I created a stub for Jeff Giansiracusa.

- Discussion Type
- discussion topicconstructive Riesz representation theorem
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Apr 8th 2011

reference for constructive proof of Riesz representation theorem