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2-categories 2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry bundles calculus categories category category-theory chern-weil-theory cohesion cohesive-homotopy-theory cohesive-homotopy-type-theory cohomology colimits combinatorics complex-geometry computable-mathematics computer-science constructive constructive-mathematics cosmology definitions deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry differential-topology digraphs duality elliptic-cohomology enriched fibration finite foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry goodwillie-calculus graph graphs gravity grothendieck group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory homological homological-algebra homotopy homotopy-theory homotopy-type-theory index-theory infinity integration integration-theory k-theory lie lie-theory limit limits linear linear-algebra locale localization logic manifolds mathematics measure-theory modal-logic model model-category-theory monads monoidal monoidal-category-theory morphism motives motivic-cohomology multicategories nonassociative noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pasting philosophy physics pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory string-theory subobject superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory type type-theory universal variational-calculus

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- Discussion Type
- discussion topicdown quark
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

stub entry, to fill in

*flavors of fundamental particles – table*

- Discussion Type
- discussion topicup quark
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

stub entry, to fill in

*flavors of fundamental particles – table*

- Discussion Type
- discussion topictauon
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

stub, to fill in

*flavors of fundamental particles – table*

- Discussion Type
- discussion topicflavors of fundamental particles -- table
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

- Discussion Type
- discussion topicYuval Grossman
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

brief

`category:people`

-entry for hyperlinking references at*flavor physics*

- Discussion Type
- discussion topicL. J. Romans
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

brief

`category:people`

-entry for hyperlinking references at*massive type IIA supergravity*(didn’t find any webpage to point to regarding Romans; if anyone has a pointer, let’s add it)

- Discussion Type
- discussion topicmassive type IIA supergravity
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

- Discussion Type
- discussion topicD8-brane
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Nov 15th 2019

- Discussion Type
- discussion topicD=10 supergravity
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 15th 2019

- Discussion Type
- discussion topicstring theory
- Category Latest Changes
- Started by Urs
- Comments 9
- Last comment by Urs
- Last Active Nov 15th 2019

I have added to string theory a new section Critical strings and quantum anomalies.

Really I was beginning to work on a new entry twisted spin^c structure (not done yet) and then I found that a summary discussion along the above lines had been missing.

- Discussion Type
- discussion topicHomePage
- Category Latest Changes
- Started by Urs
- Comments 59
- Last comment by Urs
- Last Active Nov 15th 2019

I have added at

*HomePage*in the section*Discussion*a new sentence with a new link:If you do contribute to the nLab, you are strongly encouraged to similarly drop a short note there about what you have done – or maybe just about what you plan to do or even what you would like others to do. See Welcome to the nForum (nlabmeta) for more information.

I had completly forgotton about that page

*Welcome to the nForum (nlabmeta)*. I re-doscivered it only after my recent related comment here.

- Discussion Type
- discussion topicsphere
- Category Latest Changes
- Started by Urs
- Comments 6
- Last comment by Guest
- Last Active Nov 14th 2019

- Discussion Type
- discussion topicoctonionic Hopf fibration
- Category Latest Changes
- Started by David_Corfield
- Comments 32
- Last comment by Urs
- Last Active Nov 14th 2019

Since there wasn’t a page octonionic Hopf fibration, I started one, copying over the start of quaternionic Hopf fibration. The weirdness of the octonions doesn’t prevent anything there, does it?

- Discussion Type
- discussion topicM-theory
- Category Latest Changes
- Started by David_Corfield
- Comments 7
- Last comment by Urs
- Last Active Nov 14th 2019

A stub for M-theory. What’s supposed to be so mysterious about it? Is it that people don’t even know what form it would take?

- Discussion Type
- discussion topicJames Bjorken
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 13th 2019

- Discussion Type
- discussion topicstandard model of particle physics
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Nov 13th 2019

**Edit to**: standard model of particle physics by Urs Schreiber at 2018-04-01 01:15:37 UTC.**Author comments**:added textbook reference

- Discussion Type
- discussion topicDp-D(p+4)-brane bound state
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Nov 13th 2019

- Discussion Type
- discussion topicD2-D8 brane bound state
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 13th 2019

- Discussion Type
- discussion topicKaluza-Klein mechanism
- Category Latest Changes
- Started by Urs
- Comments 16
- Last comment by Urs
- Last Active Nov 12th 2019

recently there were some questions about it here on the nForum: now there is an entry on the Kaluza-Klein mechanism

- Discussion Type
- discussion topicM2-brane
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Nov 12th 2019

added a bunch of references to

*M2-brane*

- Discussion Type
- discussion topicswampland
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Nov 12th 2019

- Discussion Type
- discussion topiclinear logic
- Category Latest Changes
- Started by Mike Shulman
- Comments 10
- Last comment by Mike Shulman
- Last Active Nov 12th 2019

The cut rule for linear logic used to be stated as

If $\Gamma \vdash A$ and $A \vdash \Delta$, then $\Gamma \vdash \Delta$.

I don’t think this is general enough, so I corrected it to

If $\Gamma \vdash A, \Phi$ and $\Psi,A \vdash \Delta$, then $\Psi,\Gamma \vdash \Delta,\Phi$.

- Discussion Type
- discussion topicmultiplicative conjunction
- Category Latest Changes
- Started by Mike Shulman
- Comments 1
- Last comment by Mike Shulman
- Last Active Nov 12th 2019

Corrected discussion of MLL and MILL, and removed redirects for MILL (those should go to linear logic.

- Discussion Type
- discussion topicstring field theory
- Category Latest Changes
- Started by Urs
- Comments 17
- Last comment by Urs
- Last Active Nov 12th 2019

I have started adding references to

*string field theory*, in particular those by Jim Stasheff et al. on the role of L-infinity algebra and A-infinity algebra. Maybe I find time later to add more details.

- Discussion Type
- discussion topicasymptotic safety
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Nov 11th 2019

- Discussion Type
- discussion topicbrane bound states -- table
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 11th 2019

- Discussion Type
- discussion topicAnirban Basu
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 11th 2019

brief

`category:people`

-entry for hyperlinking references at*Dp-D(p+2)-brane bound states*,*M2-M5-brane bound state*and at*E-string*

- Discussion Type
- discussion topicM-theory on Sp(1)-manifolds
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by David_Corfield
- Last Active Nov 11th 2019

another item for the list

*KK-compactifications of M-theory – table*just a stubby minimum so far, for the moment just so as to record references.

- Discussion Type
- discussion topicsupergravity C-field
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Nov 11th 2019

I am working on the entry supergravity C-field. On the one hand I am in the process of adding in more on the DFM model. On the other I am describing how to reformulate aspects of this in terms of infinity-Chern-Weil theory (this with Domenico Fiorenza and Hisham Sati behind the scenes).

Not done yet, so beware.

- Discussion Type
- discussion topicshifted C-field flux quantization
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Nov 11th 2019