Not signed in (Sign In)

Not signed in

Want to take part in these discussions? Sign in if you have an account, or apply for one below

  • Sign in using OpenID

Discussion Tag Cloud

Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to nForum
If you want to take part in these discussions either sign in now (if you have an account), apply for one now (if you don't).

nLab > Latest Changes: ADE singularity

Bottom of Page

1 to 17 of 17

  1.  
    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeAug 12th 2015

    Yesterday I had added some rough bits and pieces and some references to ADE singularity, and cross-linked with relevant entries such as ADE classification and M-theory on G2-manifolds. But for the moment this remains a stub.

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeApr 1st 2018

    Edit to: ADE singularity by Urs Schreiber at 2018-04-01 00:52:32 UTC.

    Author comments:

    hyperlinked pointer to textbook by Ibanez-Uranga

    • CommentRowNumber3.
    • CommentAuthorDavid_Corfield
    • CommentTimeApr 13th 2018

    The link to the pdf in

    • Martin Wijnholt, slides 6-10 of String compactification, PITP 2014 (pdf)

    wasn’t working, but I found an article of that name uploaded on nLab. But this document is not in slides form. Is the material from the old slides 6-10 contained in this document?

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeApr 13th 2018

    but I found

    Please remind me of the url that you are referring to here.

    • CommentRowNumber5.
    • CommentAuthorDavid_Corfield
    • CommentTimeApr 13th 2018

    It used to point to

    https://pitp2014.ias.edu/sites/pitp2014.ias.edu/files/PITP2014_P3_wijnholt.pdf

    which doesn’t work.

    You’ve uploaded

    https://ncatlab.org/nlab/files/WijnholtCompactification14.pdf

    which is from that conference.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeApr 13th 2018
    • (edited Apr 13th 2018)

    Thanks. Unfortunately, I don’t see the graphics anymore in that other pdf by Wijnholt.

    But this was suboptimal anyway. Meanwhile Hisham has produced the perfect graphics that should go into this entry. Once our article is out, remind me to upload a copy of that improved illustration here.

    • CommentRowNumber7.
    • CommentAuthorDavid_Corfield
    • CommentTimeApr 13th 2018

    And at Nonabelian gauge groups and chiral fermions at orbifold singularities there are the graphics and a reference to Part III of Wijnholt 14, for which the pdf works but not the slides.

    • CommentRowNumber8.
    • CommentAuthorDavid_Corfield
    • CommentTimeApr 13th 2018
    • (edited Apr 13th 2018)

    But the slides can be found at the conference site, so I may as well change the URLs.

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeApr 13th 2018

    Okay, thanks. Would be nice if you have the energy to fix it. But it’s not worth a lot of effort. In a short while I will provide a better graphics to replace that one.

    • CommentRowNumber10.
    • CommentAuthorDavid_Corfield
    • CommentTimeApr 13th 2018

    Ok, fixed on three pages.

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeApr 15th 2018
    • (edited Apr 15th 2018)

    added a more official reference by Miles Reid: Reid 87

    diff, v15, current

    • CommentRowNumber12.
    • CommentAuthorUrs
    • CommentTimeMay 6th 2018

    added pointer to the two articles by Kronheimer here on ADE-singularities in terms opf hyper-Kaehler geometry

    diff, v18, current

    • CommentRowNumber13.
    • CommentAuthorUrs
    • CommentTimeMay 6th 2018
    • (edited May 6th 2018)

    Gave the statement that the resolution of an ADE-singularity is by spheres touching along the corresponding Dynking diagram its own little Properties-subsection. Added explicit pointer to where this was first proven: duVal 1934 I, p. 1-3 (453-455)).

    Also added pointer to Kronheimers hyper-Kaehler version of the story.

    diff, v18, current

    • CommentRowNumber14.
    • CommentAuthorUrs
    • CommentTimeMay 8th 2018

    added pointer to Lamotke 86, chapter IV

    diff, v19, current

    • CommentRowNumber15.
    • CommentAuthorUrs
    • CommentTimeMay 17th 2018

    Replaced the previous graphics with a better one and added some more pointers to the string theoretic interpretation (here)

    diff, v20, current

    • CommentRowNumber16.
    • CommentAuthorUrs
    • CommentTimeSep 12th 2019

    I have cleaned-up, expanded, cross-linked and sub-sub-sectioned the list of references on ADE-singularities in string theory: here

    diff, v30, current

    • CommentRowNumber17.
    • CommentAuthorUrs
    • CommentTimeMay 9th 2022

    I have added one more subsection with references, concerning type II string/D-branes on A(DE)-type singularities:

    Have taken the liberty of adding a self-reference at the end:

    The observation that the worldsheet 2d CFT correspoding to a string probing (a D-brane on) an A κ−1A_{\kappa-1}-type singularity ℍ/ C κ+2\mathbb{H}/_{C_{\kappa + 2}} is the chiral WZW model for the affine Lie algebra su(2) at level κ−2\kappa - 2 (plus some trivial summands):

    On how this 𝔰𝔲(2)^ κ−2\widehat{\mathfrak{su}(2)}^{\kappa-2}-CFT encodes the BPS states of SU(κ)SU(\kappa)-SYM on D3-branes transverse to the singularity:

    An interpretation of this phenomenon, under the expected K-theory classification of D-brane charge, as due to the (somewhat neglected) sector of twisted equivariant K-theory where the twist is by an inner local systems which may appear inside an A-type singularity:

    diff, v32, current

1 to 17 of 17

  1.