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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeJul 22nd 2011
   • PermaLink
   Author: Urs
   Format: MarkdownItexstub for [[T-fold]]

   stub for T-fold

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeFeb 26th 2014
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded a pointer to Thomas Nikolaus' talk as of yesterday to _[[T-fold]]_. (I wish there were more to link to at the moment, but at least the broad statement should be recorded for the time being.)

   added a pointer to Thomas Nikolaus’ talk as of yesterday to T-fold.

   (I wish there were more to link to at the moment, but at least the broad statement should be recorded for the time being.)

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeFeb 26th 2014
   • PermaLink
   Author: Urs
   Format: MarkdownItexso for completeness I gave _[[T-duality 2-group]]_ its own entry

   so for completeness I gave T-duality 2-group its own entry

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeApr 4th 2018
   • (edited Apr 4th 2018)
   • PermaLink
   Author: Urs
   Format: MarkdownItexFinally Thomas Nikolaus and Konrad Waldorf have written up their formalization of Chris Hull's idea of [[T-folds]], in terms of the [[higher differential geometry]] of [[principal 2-bundles]] for the [[T-duality 2-group.]] I have added a pointer as [Nikolaus-Waldorf 18](https://ncatlab.org/nlab/show/T-fold#NikolausWaldorf18). <a href="https://ncatlab.org/nlab/revision/diff/T-fold/13">diff</a>, <a href="https://ncatlab.org/nlab/revision/T-fold/13">v13</a>, <a href="https://ncatlab.org/nlab/show/T-fold">current</a>

   Finally Thomas Nikolaus and Konrad Waldorf have written up their formalization of Chris Hull’s idea of T-folds, in terms of the higher differential geometry of principal 2-bundles for the T-duality 2-group. I have added a pointer as Nikolaus-Waldorf 18.

   diff, v13, current

5. • CommentRowNumber5.
   • CommentAuthorUrs
   • CommentTimeNov 6th 2019
   • (edited Nov 6th 2019)
   • PermaLink
   Author: Urs
   Format: MarkdownItexslightly expanded and re-organized the Idea-text. (But it remains a stub.) <a href="https://ncatlab.org/nlab/revision/diff/T-fold/18">diff</a>, <a href="https://ncatlab.org/nlab/revision/T-fold/18">v18</a>, <a href="https://ncatlab.org/nlab/show/T-fold">current</a>

   slightly expanded and re-organized the Idea-text. (But it remains a stub.)

   diff, v18, current

6. • CommentRowNumber6.
   • CommentAuthorUrs
   • CommentTimeJul 19th 2022
   • (edited Jul 19th 2022)
   • PermaLink
   Author: Urs
   Format: MarkdownItexI have given the references on the higher geometric formulation its own subsection ([here](https://ncatlab.org/nlab/show/T-fold#ReferencesViaHigherGeometry)) and then I have added these: *** The [[automorphism 2-group]] of the [[T-duality 2-group]] (and hence potentially the full structure of T-folds) is determined in: * [[Konrad Waldorf]], *Categorical symmetries of T-duality* &lbrack;[arXiv:2202.09187](https://arxiv.org/abs/2202.09187), [spire:2035224](https://inspirehep.net/literature/2035224)&rbrack; Introduction and review: * [[Konrad Waldorf]], *Stacks, Gerbes and T-Duality*, talk notes, Adelaide (2019) &lbrack;[pdf](http://math.konradwaldorf.de/www/link.php?lg=en&link=257&savename=Waldorf-Stacks-Gerbes-and-T-Duality.pdf)&rbrack; Proposals for further generalization ([[connection on a 2-bundle|2-connections]] and further [[non-geometric backgrounds]]): * [[Hyungrok Kim]], [[Christian Saemann]], *Non-Geometric T-Duality as Higher Groupoid Bundles with Connections* &lbrack;[arXiv:2204.01783](https://arxiv.org/abs/2204.01783)&rbrack; *** <a href="https://ncatlab.org/nlab/revision/diff/T-fold/22">diff</a>, <a href="https://ncatlab.org/nlab/revision/T-fold/22">v22</a>, <a href="https://ncatlab.org/nlab/show/T-fold">current</a>

   I have given the references on the higher geometric formulation its own subsection (here) and then I have added these:

   ---

   The automorphism 2-group of the T-duality 2-group (and hence potentially the full structure of T-folds) is determined in:

   • Konrad Waldorf, Categorical symmetries of T-duality [arXiv:2202.09187, spire:2035224]

   Introduction and review:

   • Konrad Waldorf, Stacks, Gerbes and T-Duality, talk notes, Adelaide (2019) [pdf]

   Proposals for further generalization (2-connections and further non-geometric backgrounds):

   • Hyungrok Kim, Christian Saemann, Non-Geometric T-Duality as Higher Groupoid Bundles with Connections [arXiv:2204.01783]

   ---

   diff, v22, current

7. • CommentRowNumber7.
   • CommentAuthorUrs
   • CommentTimeDec 10th 2022
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to: * [[Peter Bouwknegt]], [[Ashwin S. Pande]], *Topological T-duality and T-folds*, Advances in Theoretical and Mathematical Physics **13** 5 (2009) &lbrack;[arXiv:0810.4374](https://arxiv.org/abs/0810.4374), [doi:10.4310/ATMP.2009.v13.n5.a6](https://dx.doi.org/10.4310/ATMP.2009.v13.n5.a6)&rbrack; <a href="https://ncatlab.org/nlab/revision/diff/T-fold/23">diff</a>, <a href="https://ncatlab.org/nlab/revision/T-fold/23">v23</a>, <a href="https://ncatlab.org/nlab/show/T-fold">current</a>

   added pointer to:

   • Peter Bouwknegt, Ashwin S. Pande, Topological T-duality and T-folds, Advances in Theoretical and Mathematical Physics 13 5 (2009) [arXiv:0810.4374, doi:10.4310/ATMP.2009.v13.n5.a6]

   diff, v23, current