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- Discussion Type
- discussion topicFinite dimensions
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Oct 28th 2013

There is a deliberately ambiguous stub at finite-dimensional space.

We might collect there all of the nice things about finite-dimensional spaces (for various notions of ’space’).

- Discussion Type
- discussion topicFormal reality
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Oct 28th 2013

Marc Hoyois created formally real field back in August (which was never announced here), and now I've created formally real algebra (and linked them to one another).

- Discussion Type
- discussion topicsymplectic integrator
- Category Latest Changes
- Started by zskoda
- Comments 7
- Last comment by Urs
- Last Active Oct 25th 2013

Stub symplectic integrator, just a list of basic references so far, redirecting aslo multisymplectic integrator.

- Discussion Type
- discussion topicparameterized cohesive spectra
- Category Latest Changes
- Started by Urs
- Comments 66
- Last comment by David_Corfield
- Last Active Oct 24th 2013

have added a paragraph

*tangent infinity-category – Tangent infinity topos*meant to extract the argument from Joyal’s “Notes on Logoi” that the tangent $\infty$-category of an $\infty$-topos is an $\infty$-topos. Then a remark on how this should imply that the tangent $\infty$-topos of a cohesive topos is itself cohesive over the tangent base $\infty$-topos.I am not making any claims tonight, just sketching an argument. Hope to come back to it tomorrow when I am awake again.

- Discussion Type
- discussion topicsmooth super infinity-groupoid
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Oct 23rd 2013

I have started a stub for smooth super infinity-groupoids, with the evident definition and observation that this is cohesive, but nothing else so far. To be worked on. (similar to locally-contractible infinity-groupoid)

- Discussion Type
- discussion topicp-divisible groups
- Category Latest Changes
- Started by hilbertthm90
- Comments 14
- Last comment by Mike Shulman
- Last Active Oct 23rd 2013

I’ve constructed the page p-divisible group since I need it for my height of a variety page. I have to admit that I’m incredibly embarrassed that no matter how many times I look up the words “directed” “inductive” “projective” “limit” “colimit” etc I never seem to use them correctly. All of the systems are as I showed $G_{\nu}\to G_{\nu +1}$ I thought this corresponded to directed, inductive, or colimit, but when I looked up inductive limit in the nlab it seemed to be indicating the opposite, so maybe some of the uses are wrong.

- Discussion Type
- discussion topic2-sheaf
- Category Latest Changes
- Started by Urs
- Comments 14
- Last comment by Urs
- Last Active Oct 23rd 2013

In the References-section at

*2-sheaf*I have added three “classical” references:in the 1970s Grothendieck, Giraud and then Bunge usually considered “2-sheaves” – namely category-valued stacks – by default. Also there is a good body of work on 2-sheaves realized as

*internal categories*in the underlying 1-sheaf topos. I have added a pointer to Joyal-Tierney’s*Strong stacks*so far, but I think much more literature exists in this direction.But if one goes this internalization-route at all, what one should

*really*do is, I think, consider weak internal categories in the (2,1)-topos over the underlying site.Has this been studied at all? Does anyone know how 2-categories of weak internal categories in $(2,1)$-toposes relate to 2-toposes? At least under nice conditions these should be equivalent, I guess. But I want to understand this better.

- Discussion Type
- discussion topicdifferentiable (infinity,1)-category
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Oct 22nd 2013

brief entry

*differentiable (infinity,1)-category*

- Discussion Type
- discussion topicJB-algebras
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Oct 22nd 2013

That is, Jordan–Banach algebras (although there is actually a distinction between these).

- Discussion Type
- discussion topicLagrange inversion
- Category Latest Changes
- Started by zskoda
- Comments 1
- Last comment by zskoda
- Last Active Oct 17th 2013

Lagrange inversion, redirecting also Lagrange inversion formula and Lagrange inversion theorem, previously wanted at Lambert W-function, noncommutative symmetric function and at Faà di Bruno formula.

- Discussion Type
- discussion topicEndofunctions
- Category Latest Changes
- Started by TobyBartels
- Comments 8
- Last comment by zskoda
- Last Active Oct 15th 2013

I don't know why we never had endofunction, but we didn't; now we do.

- Discussion Type
- discussion topicFunctionals and operators
- Category Latest Changes
- Started by TobyBartels
- Comments 3
- Last comment by TobyBartels
- Last Active Oct 14th 2013

I have made functional and operator primarily about the meanings of these in higher-order logic, where these terms are used exclusively and unqualified. I have accordingly split off linear functional from functional; linear operator (redirecting to linear map) was already separate from operator (which was only for disambiguation). I have also checked each incoming link to functional or operator (or a plural form) to link instead to linear functional or linear operator when appropriate.

That said, there are such things as nonlinear functionals and operators on abstract vector spaces, things which are also not functionals or operators in the type-theoretic sense. Possibly we would want pages such as nonlinear functional and nonlinear operator to cover these. (Compare nonassociative algebra, which covers a topic more general than what is covered at associative algebra but also could not be covered at simply algebra.)

I did not know what to do with the phrase ‘various discretised versions are interesting in finite geometries as well as numerical analysis’. Are these linear functionals, type-theoretic functionals, both, or neither?

- Discussion Type
- discussion topicPower to the power-associative people!
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Oct 14th 2013

The revolution will not be televised, but it will be wikified at power-associative algebra.

- Discussion Type
- discussion topicPolarization identities.
- Category Latest Changes
- Started by TobyBartels
- Comments 3
- Last comment by jim_stasheff
- Last Active Oct 14th 2013

I created polarization identity and added some disambiguation to polarization.

- Discussion Type
- discussion topicSuper Gerbes
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Oct 13th 2013

With our “String Geometry Network” we have another meeting in October at the Max-Planck Institute for Mathematics in Bonn.

In each such meeting we have, besides research talks and discussion sessions, a kind of “reading course”, something to get us all on the same page of some topic.

This time the idea is to talk about higher supergeometry and “super-string geometry”, if you wish. I am preparing some notes to go with this, and naturally I got inclined to prepare them on the nLab. They will be developing here in the entry

Currently there is just an introduction and then a session outline with just a few linked keywords. I’ll be developing this as days go by. Depending on which reactions I get, there might be drastic revisions, or just incremental extension. We’ll see.

- Discussion Type
- discussion topicYetter model
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active Oct 11th 2013

started Yetter model, still a stub so far. Tim, I trust you will add references?! :-)

- Discussion Type
- discussion topicReedy category with fibrant constants
- Category Latest Changes
- Started by Karol Szumiło
- Comments 4
- Last comment by Karol Szumiło
- Last Active Oct 8th 2013

New entry: Reedy category with fibrant constants.

- Discussion Type
- discussion topicorder-theoretic structure in quantum mechanics
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Oct 6th 2013

Circumstances prompted me to write a kind of pamphlete pointing out some aspects that seem worth taking notice of have not found much appreciation yet:

This surveys how basic theorems about the standard foundation of quantum mechanics imply an accurate geometric incarnation of the “phase space in quantum mechanics” by an order-theoretic structure that combines with an algebraic structure to a ringed topos, the “Bohr topos”. While the notion of Bohr topos has been

*motivated*by the Kochen-Specker theorem, the point here is to highlight that taking into account further theorems about the standard foundations of quantum mechanics, the notion effectively follows automatically and provides an accurate and useful description of the geometry of “quantum phase space” also in quantum field theory.

- Discussion Type
- discussion topicClebsch-Gordan coefficients
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 4th 2013

created

*Clebsch-Gordan coefficients*

- Discussion Type
- discussion topic2-groups
- Category Latest Changes
- Started by DavidRoberts
- Comments 1
- Last comment by DavidRoberts
- Last Active Oct 4th 2013

I added Sinh’s thesis plus a link to a scan to 2-group

- Discussion Type
- discussion topicdaseinisation
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Todd_Trimble
- Last Active Oct 3rd 2013

brief entry “daseinisation”

(Note: I am not embracing the term, I just happen to want to record that somebody proposed it.)

- Discussion Type
- discussion topicspectral presheaf
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 2nd 2013

brief entry for

*spectral presheaf*

- Discussion Type
- discussion topicEnveloping von Neumann algebras
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Sep 29th 2013

Zoran started enveloping von Neumann algebra earlier this month; I've added more characterizations and something about uses.

- Discussion Type
- discussion topicend compactification
- Category Latest Changes
- Started by Tim_Porter
- Comments 5
- Last comment by TobyBartels
- Last Active Sep 29th 2013

There was already a discussion of ends in the topological sense at proper homotopy. (I had never seen the term hemicompact before. I knew of $\sigma$-compact which is almost the same.)

- Discussion Type
- discussion topicGeometric interpretation of torsion
- Category Latest Changes
- Started by Bruce Bartlett
- Comments 7
- Last comment by Urs
- Last Active Sep 24th 2013

I’d like to add some sentences describing a geometric understanding of the “torsion” of a connection on a Riemannian manifold to torsion. But perhaps my understanding of torsion is wrong, so I’m running it by you guys first. I wrote it down on math overflow and I’m curious what people think.

- Discussion Type
- discussion topicKaluza-Klein mechanism
- Category Latest Changes
- Started by Bruce Bartlett
- Comments 9
- Last comment by Bruce Bartlett
- Last Active Sep 23rd 2013

Added a link to an expository talk I gave on “The geometry of force” giving an elementary explanation of the classical Kaluza-Klein mechanism (i.e. the idea that geodesics on the principal bundle project down to curved trajectories on base space apparently experiencing a “force”). Following the book of Bleecker, Gauge theory and variational principles.

- Discussion Type
- discussion topiccanonical-ness and constructivism
- Category Latest Changes
- Started by Urs
- Comments 27
- Last comment by Urs
- Last Active Sep 22nd 2013

This came up in another thread, where it was not really on-topic. I want to re-post it here so that it gets due attention and maybe finds a resolution:

I find the content at

*canonical morphism*unsatisfactory to the extent that I am voting to replace it by something else.First why I find it unsatisfactory: the entry describes a proposal by Jim Dolan from some time ago for how to give a formal meaning to the colloquial use of “canonical” in mathematics, but it seems to me that

nobody, not even Jim Dolan himself, ever used that in practice;

it does not actually capture much at all about the colloquial use of “canonical” (see below for a proposal of mine of what a proper formalization would involve);

the only almost-application mentioned at the bottom of the entry, which is about morphisms of QFTs, has nothing of the “canonical” flavor to it at all (on the contrary!), and the curious notion discussed there actually becomes natural if one instead considers QFTs with boundaries, as formalized on the last pages of Lurie’s “classification of TFT” article.

In summary, I find that the article gives an ill-motivated definition which is actually misleading and has no support from usage/practice.

If this sounds harsh, please take it as motivation to convince me otherwise. I’ll be happy to be convinced by a good argument and will use it to improve the entry accordingly.

But currently I think the entry content should be replaced with something else. I would tend to think that a formalization of “canonical” should involve something as follows, instead.

It should involve some notion of constructiveness. What is

*canonical*, in colloquial meaning of the word, is that which we can actually construct, with given data (given*terms*).For instance for $X$ just any set without further information, the reason why $id \colon X \to X$ is the

*canonical*map from $X$ to itself is because this is the only one we can actually*name*, whose term we can actually construct. There are all these other maps, but we can’t actually name them with the given information.Or: the reason why $(x,y) \colon \mathbb{R}^2 \longrightarrow \mathbb{R}$ are the

*canonical*coordinates on the plane is because they are the two which one can actually construct given the data by which the plane $\mathbb{R}^2$ was constructed, namely the two projection maps out of the project. The reason why all the other coordinates that we might put on $\mathbb{R}^2$ are “not canonical” is that while they “exist” in the sense of existence of mathematics, we cannot actually*construct*them with the given data.I expect that somebody with more genuine type-theoretical practice can easily see what I am getting at here and maybe give it a more pronounced formulation.

- Discussion Type
- discussion topicglobal model structure on functor
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Tim_Porter
- Last Active Sep 20th 2013

added to global model structure on functors that theorem that the projective and the injective global model structure on functors with values in a combinatorial model category is itself again a combinatorial model category.

- Discussion Type
- discussion topicDwyer map
- Category Latest Changes
- Started by Karol Szumiło
- Comments 2
- Last comment by Urs
- Last Active Sep 20th 2013

Started Dwyer map.

- Discussion Type
- discussion topic(oo,1)-categorical hom-space
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Zhen Lin
- Last Active Sep 18th 2013

I added a section Hom-spaces between cofibrant/fibrant objects with a few lemmas and their proofs at

(infinity,1)-categorical hom-space.

(The proofs are intentionally very small-step and hopefully "pedagogical".)

I also reworded the introduction part a bit and replied further in the old query box there.

Effectively my point is: I am not overly happy with the title of that entry myself, but the alternatives proposed so far still strike me as worse. The main deficiency of the title is that it may sound a bit awkward. But it has the advantage of being fairly accuratively descriptive.

But I won't be dogmatic about this. If there is a wide-spread desire to rename the entry, please feel free to do so.

- Discussion Type
- discussion topicHamiltonian n-vector field
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 17th 2013

created an entry

*Hamiltonian n-vecotr field*(redirecting*Hamiltonian multivector field*) with the definition of the “de Donder-Weyl”-Hamiltonian flows of $n$-volumes and, secondly. with some comments on how to interpret this in higher geometry. Will further expand on this second piece a little later, need to interrup now.

- Discussion Type
- discussion topicreduced phase space
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 15th 2013

I have split off

*reduced phase space*from*covariant phase space*and started to expand a bit.In particular I tried to highlight a bit the important point that the

*exact*presymplectic form which is induced by any local action functional on its covariant phase space (as discussed there), still has to be equipped with*equivariant structure*as a U(1)-prinicipal connection in order to pass to the reduced phase space.This is an obvious point that however I find is glossed over in much of the literature and leads to some confusion in some places: some literature fond of the covariant phase space-construction from local action functionals will highlight that this always has

*exact*presymplectic form and will take this as reason to disregard all the subtleties of geometric quantization, which pretty much disappear for exact (pre-)symplectic forms. The point missed in such discussion is that there is non-trivial equivarint structure on the prequantization of this presymplectic form.This subtlety as such is of course treated correctly in all of the mathematical literature listed at

*qauzntization commutes with reduction*, of course. But that literature in turn doesn’t mention the important construction of covariant phase spaces from local Lagrangians.Therefore, if anyone can point me to references that do BOTH of the following:

discuss the covariant presymplectic phase space induced form a local Lagrangian;

discuss the need to put equivariant connection structure on the canonically induced globally defined presymplectic potential;

I’d be grateful.

- Discussion Type
- discussion topicChu spaces
- Category Latest Changes
- Started by Tim_Porter
- Comments 1
- Last comment by Tim_Porter
- Last Active Sep 15th 2013

To complement the entry on Chu construction, I have created a new entry on Chu spaces, simple examples, which I hope to link up with the formal concept analysis entry.

- Discussion Type
- discussion topicLocalizable measures
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Sep 14th 2013

I created localizable measure to record the definition. Needs more properties.

- Discussion Type
- discussion topicOpposite poset
- Category Latest Changes
- Started by TobyBartels
- Comments 1
- Last comment by TobyBartels
- Last Active Sep 14th 2013

I created opposite poset to satisfy some links.

- Discussion Type
- discussion topicwitten.pdf
- Category Latest Changes
- Started by Tim_Porter
- Comments 4
- Last comment by TobyBartels
- Last Active Sep 13th 2013

Someone has created www.maths.ed.ac.uk/~aar/papers/witten.pdf. This seems to me a strange thing to do. It is perhaps someone just trying out code.

- Discussion Type
- discussion topicoff-shell Poisson bracket
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by jim_stasheff
- Last Active Sep 12th 2013

am making some notes at

*off-shell Poisson bracket*, based on a discussion that I am having with Igor Khavkine

- Discussion Type
- discussion topicextended supersymmetry
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 11th 2013

gave

*extended supersymmetry*its own entry (the content had previously been scattered around in other entries)

- Discussion Type
- discussion topicVelo-Zwanziger problem
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 10th 2013

brief entry for

*Velo-Zwanziger problem*

- Discussion Type
- discussion topicGlobal analytic geometry and analytic Langlands program
- Category Latest Changes
- Started by fpaugam
- Comments 52
- Last comment by David_Corfield
- Last Active Sep 10th 2013

- After reading some thread on mathoverflow, i decided to create the global analytic geometry and analytic Langlands program entries. The first one is now well started by Berkovich and Poineau mainly.

The analytic Langlands program is an idea of mine that is not very precise but i am convinced would help beginners in arithmetic geometry to understand quickly important aspects of arithmetic problems, and develop interest for global analytic geometry. The point is to understand better why Langlands program is so hard using schemes and would be easier using analytic geometry. This is also true with the use of ind-schemes in local geometric langlands and Chiral algebras that should be replaced by t-adic analytic tools.

Creating an entry on this would help put all references on the subject and make them better available.

- Discussion Type
- discussion topicPeierls bracket
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Sep 9th 2013

at

*Peierls bracket*I have added a bunch of further references and have slightly expanded the Idea-section

- Discussion Type
- discussion topicgeometric quantization of symplectic groupoids
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Sep 9th 2013

I have split off an entry geometric quantization of symplectic groupoids from symplectic groupoid.

I have also tried to clean up and make more systematic the Idea-section at geometric quantization

- Discussion Type
- discussion topicmotivic quantization -- Expositional survey
- Category Latest Changes
- Started by Urs
- Comments 34
- Last comment by Urs
- Last Active Sep 9th 2013

I have now what should be a readable pre-version of

This still needs a round of polishing or two. But it should be at least readable.

If anyone is interested, have a look, be critical and try to poke holes into it.

- Discussion Type
- discussion topiclattice renormalization
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 9th 2013

added some references to

*lattice field theory*and*lattice renormalization*. Though I am still looking for a reference on the latter that states the basic mechanism clearly…

- Discussion Type
- discussion topicsuperselection sector
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 9th 2013

at

*superselection sector*I tried to state more explicitly the fact that superselection sectors are equivalently the irreps of the algebra of observables in the space of quantum states.Also cross-linked with

*irreducible representation*and with*quantum observable*.

- Discussion Type
- discussion topicNewton's laws of motion
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Sep 8th 2013

over at

*prequantized Lagrangian correspondence*I needed to point to Newton’s laws, so I have started an entry*Newton’s laws of motion*. So far mainly it just contains briefly the content of Newton’s laws in modern language.

- Discussion Type
- discussion topicmotivating quantum mechanics from classical mechanics + Lie theory
- Category Latest Changes
- Started by Urs
- Comments 23
- Last comment by Urs
- Last Active Sep 5th 2013

prompted by this physics.SE question I ended up adding to Idea-section of the entry

*quantization*a new subsection titled*Motivation from classical mechanics and Lie theory*.

- Discussion Type
- discussion topicLocal sections
- Category Latest Changes
- Started by DavidRoberts
- Comments 22
- Last comment by TobyBartels
- Last Active Sep 4th 2013

Changed the page local section to discuss a slightly more general concept than the local sections of a bundle, and over a more general pretopology.

- Discussion Type
- discussion topicgeometric representation theory
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by David_Corfield
- Last Active Sep 2nd 2013

added to

*geometric representation theory*a quote of program description of the MSRI program next year.

- Discussion Type
- discussion topicworldvolume/target supersymmetry of brane sigma-models -- table
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by TobyBartels
- Last Active Sep 1st 2013

had need for a small table

*worldvolume-target supersymmetry of brane sigma-models*and so I created one. Have included it into the relevant entries.Also created a stub for

*superembedding approach*, the middle entry of the table.(An nForum issue: as of late I get to see the nForum

*only*in its plain HTML-form, which is very inconvenient. Is this a problem just on my side, or does anyone else experience this?)

- Discussion Type
- discussion topicPseudocompact algebras
- Category Latest Changes
- Started by Tim_Porter
- Comments 6
- Last comment by zskoda
- Last Active Aug 31st 2013

As we were discussing profinite completions the other day in another thread I thought I would add in some points about completed group algebras at profinite group and add some mention of pseudo compact algebras to the pre-existing entry on pseudocompact rings.

It is not clear to me what the connection between these algebras and profinite algebras should be. These pseudocompact and related linear compact algebras use finite dimensionality instead of finiteness to get a sort of algebraic compactness condition.

- Discussion Type
- discussion topicsuper Poincare Lie algebra
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Aug 30th 2013

created super Poincare Lie algebra

linked to it from super Euclidean group and from supergravity

- Discussion Type
- discussion topicPolchinski: String theory
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 29th 2013

I have Polchinski’s textbook a category:reference-entry

*String theory*, for purposes of better linking to it

- Discussion Type
- discussion topichigher spin geometry - contents
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by David_Corfield
- Last Active Aug 29th 2013

started a topic cluster table of contents

*higher spin geometry - contents*and included it as a “floating table of contents” into relevant entries

- Discussion Type
- discussion topicLocus
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active Aug 29th 2013

Started locus following this discussion.

Should left exact localization link to reflective sub-(infinity,1)-category?

- Discussion Type
- discussion topicReferences to differential cohomology in a cohesive topos
- Category Latest Changes
- Started by DavidRoberts
- Comments 3
- Last comment by DavidRoberts
- Last Active Aug 29th 2013

I added a link to the published version of my notes on universal simplicial bundles, here on Urs’ web.

- Discussion Type
- discussion topiccharge conjugation matrix
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 28th 2013

brief remark

*charge conjugation matrix*, just because I needed to be able to point to it

- Discussion Type
- discussion topicsuper translation Lie algebra
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 28th 2013

added little bit more to

*super translation Lie algebra*, including a remark that it is a central extension of the superpoint, regarded as an abelian super Lie algebra.

- Discussion Type
- discussion topicFive lectures on supersymmetry
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 28th 2013

started a hyperlinked index for Dan Freed’s

*Five lectures on supersymmetry*(might use this in a course later this year…)

- Discussion Type
- discussion topictopological M2 on G2-manifolds
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Aug 27th 2013

I only noticed now that the discussion around equation (2.14) in

- Ling Bao, Viktor Bengtsson, Martin Cederwall, Bengt Nilsson,
*Membranes for Topological M-Theory*(arXiv:hep-th/0507077)

identifies the exceptional super Lie algebra $(2+2)$cocycle on $\mathfrak{siso}(7)$ (given by the brane scan) with the “topological membrane” of “topological M-theory”.

I added a brief remark to this extent to

*topological membrane*and updated*brane scan*accodingly. Hope to be expanding on this soon…- Ling Bao, Viktor Bengtsson, Martin Cederwall, Bengt Nilsson,