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- Discussion Type
- discussion topicgravitational instanton
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 19th 2020

- Discussion Type
- discussion topicYang-Mills instanton
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Oct 19th 2020

added to Yang-Mills instanton a discussion of instantons as tunnelings between Chern-Simons vacua.

- Discussion Type
- discussion topicDirac charge quantization
- Category Latest Changes
- Started by Urs
- Comments 4
- Last comment by Urs
- Last Active Oct 19th 2020

- Discussion Type
- discussion topicnon-perturbative effect
- Category Latest Changes
- Started by Urs
- Comments 3
- Last comment by Urs
- Last Active Oct 19th 2020

added an Idea-paragraph to

*non-perturbative effect*, also to*perturbation theory - divergence/convergence*.

- Discussion Type
- discussion topicAdam Marsh
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 19th 2020

brief

`category:people`

-entry for hyperlinking references at*fiber bundles in physics*and*mathematical physics*

- Discussion Type
- discussion topicfiber bundles in physics
- Category Latest Changes
- Started by Urs
- Comments 18
- Last comment by Urs
- Last Active Oct 19th 2020

Started an entry in “category:motivation” on

*fiber bundles in physics*.(prompted by this Physics.SE question)

- Discussion Type
- discussion topicAndrew Hanson
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 19th 2020

- Discussion Type
- discussion topicGeometry, Topology and Physics
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Oct 19th 2020

- Discussion Type
- discussion topicMikio Nakahara
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 19th 2020

- Discussion Type
- discussion topicstring theory
- Category Latest Changes
- Started by Urs
- Comments 13
- Last comment by Urs
- Last Active Oct 19th 2020

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 topicHenri Cartan
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 19th 2020

added pointer to:

- John Frank Adams,
*The work of M. H. Cartan in its relation with homotopy theory*, Colloque analyse et topologie,Astérisque no. 32-33 (1976), p. 29-41 (numdam:AST_1976__32-33__29_0/)

- John Frank Adams,

- Discussion Type
- discussion topicBredon cohomology
- Category Latest Changes
- Started by Urs
- Comments 32
- Last comment by Urs
- Last Active Oct 19th 2020

`<p>I added three more references to <a href="http://ncatlab.org/nlab/show/Bredon+cohomology">Bredon cohomology</a>.</p> <p>two of them, by H. Honkasolo, discuss a sheaf-cohomology version of Bredon cohomology, realized as the cohomology of a topos built from the <a href="http://ncatlab.org/nlab/show/orbit+category">orbit category</a>.</p> <p>It's too late for me today now to follow this up in detail, but I thought this might be of interest in the light of our discussion at <a href="http://www.math.ntnu.no/~stacey/Vanilla/nForum/comments.php?DiscussionID=650&page=1">G-equivariant stable homotopy theory</a>.</p>`

- Discussion Type
- discussion topicclassical double copy
- Category Latest Changes
- Started by Luigi
- Comments 14
- Last comment by Urs
- Last Active Oct 19th 2020

- Discussion Type
- discussion topicErnst Zermelo
- Category Latest Changes
- Started by David_Corfield
- Comments 1
- Last comment by David_Corfield
- Last Active Oct 18th 2020

- Discussion Type
- discussion topicD=6 N=(1,0) SCFT
- Category Latest Changes
- Started by Urs
- Comments 7
- Last comment by Urs
- Last Active Oct 18th 2020

- Discussion Type
- discussion topicAuguste Sagnotti > history
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 18th 2020

apparently this was a typo for and duplicate of

*Augusto Sagnotti*– am clearing the entry (a stub anyway), adding redirect to the proper entry

- Discussion Type
- discussion topicsequent calculus
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by atmacen
- Last Active Oct 18th 2020

started adding rules to sequent calculus, but have to interrup now and hunt some food

- Discussion Type
- discussion topicE-string
- Category Latest Changes
- Started by Urs
- Comments 5
- Last comment by Urs
- Last Active Oct 18th 2020

Brief idea of the

*E-string*, pointer to and snippet from one reference that makes it nicely explicit.I am compiling this and related entries because we have a clean mathematical formalization of this zoo of structures now in terms of equivariant super homotopy theory (as surveyed here). Once everything is cleaned up and published, I will try to go through all the entries and accompany the vague Idea-sections with some solid mathematics.

- Discussion Type
- discussion topicHořava-Witten theory
- Category Latest Changes
- Started by Urs
- Comments 16
- Last comment by Urs
- Last Active Oct 17th 2020

stub for Hořava-Witten theory

- Discussion Type
- discussion topicPiotr Hajac
- Category Latest Changes
- Started by Urs
- Comments 1
- Last comment by Urs
- Last Active Oct 17th 2020

- Discussion Type
- discussion topicparallel transport
- Category Latest Changes
- Started by Urs
- Comments 10
- Last comment by Urs
- Last Active Oct 17th 2020

wrote parallel transport (which was previously redirecting to connection on a bundle).

Also rewrote Dyson formula.

- Discussion Type
- discussion topicsequentially compact topological space
- Category Latest Changes
- Started by Urs
- Comments 8
- Last comment by Urs
- Last Active Oct 17th 2020

I have touched the Examples-section at

*sequentially compact topological space*:moved the detailed discussion of the compact space $\{0,1\}^{[0,1]}$ which is not sequ compact to the examples-section at

*compact topological space*, and left a pointer to it,added pointers (just pointers for the moment) to two detailed discussions of examples of sequ compact spaces that are not compact.

- Discussion Type
- discussion topicassociahedron
- Category Latest Changes
- Started by Urs
- Comments 11
- Last comment by Richard Williamson
- Last Active Oct 17th 2020

Jim Stasheff pointed out a reference that discusses categorifications of associahedra. I added the ref to associahedron

- Discussion Type
- discussion topicmoduli stack of formal groups
- Category Latest Changes
- Started by nLab edit announcer
- Comments 1
- Last comment by nLab edit announcer
- Last Active Oct 16th 2020

- Discussion Type
- discussion topicSchanuel topos
- Category Latest Changes
- Started by Thomas Holder
- Comments 12
- Last comment by Thomas Holder
- Last Active Oct 16th 2020

Added a reference to

- {#JW84}André Joyal, Gavin Wraith,
*Eilenberg-MacLane Toposes and cohomology*, pp.117-131 in Cont. Math.**92**AMS 1984.

- {#JW84}André Joyal, Gavin Wraith,

- Discussion Type
- discussion topicatomic topos
- Category Latest Changes
- Started by Dexter Chua
- Comments 3
- Last comment by Hurkyl
- Last Active Oct 16th 2020

Created the page atomic topos and moved some of the material from atomic geometric morphism over.

- Discussion Type
- discussion topicM-theory on G2-manifolds
- Category Latest Changes
- Started by Urs
- Comments 15
- Last comment by Urs
- Last Active Oct 15th 2020

started

*M-theory on G2-manifolds*

- Discussion Type
- discussion topicneutrino
- Category Latest Changes
- Started by Urs
- Comments 14
- Last comment by Urs
- Last Active Oct 15th 2020

added some comments on history to

*neutrino*.

- Discussion Type
- discussion topicleptoquark
- Category Latest Changes
- Started by Urs
- Comments 35
- Last comment by Urs
- Last Active Oct 15th 2020

- Discussion Type
- discussion topicrenormalization group
- Category Latest Changes
- Started by Urs
- Comments 2
- Last comment by Urs
- Last Active Oct 14th 2020

added to

*renormalization group*the explanation of how the Stückelberg-Petermann renormalization group relates to the Gell-Mann-Low renormalization cocycle (in general not a group).For the moment and for completeness, I copied the same text into these three entries. All these entries are still stubs. They will pick up more distinct content in a while..