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

Site Tag Cloud

2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry book bundles calculus categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration foundation foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck group 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 integration integration-theory k-theory lie-theory limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology nforum nlab noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pages 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 sheaves simplicial space spin-geometry stable-homotopy-theory stack string string-theory superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

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).
  1. I'm planning to write a divertissement on 0-dimensional TQFT and singular cohomology. The idea is that is well known (at least after Segal-Stolz-teichner approach to elliptic cohomology) that the "space" of all 1-dimensional Euclidean (or Riemannian) field theories is the spectrum of K-theory. In particular Riemannian 1-dimensional bordism with a target manifold X describes the K-theory of X. This is usually takes as the starting point towards the spectrum of elliptic cohomology, i.e., one goes from 1-dimensional to 2-dimensional field theories. In the note I'm planning I'd like to go a step back, i.e, to investigate the apparently trivial space of 0-dimensional field theories and to show how one obtains the spectrum of singular cohomology from it. As an illustrative example, considering 0-dimensional bordism with a target X amounts to considering infinite symmetric powers of X, and the Dold-Thom theorem comes into the TQFT picture.

    A second -more serious- step would consist in going from 1-dimensional to 0-dimensional field theories and read the Chern character in this framework.

    I'm pretty sure all of this is well known, but I've been unable to find any satisfactory reference (any suggestion?) so I decided to write a note (on the 0-dimensional case, for the moment). Any comment/criticism/exchange of thoughts/collaboration is welcome and encouraged.
    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeDec 18th 2009
    • (edited Dec 18th 2009)
    This comment is invalid XHTML+MathML+SVG; displaying source. <div> <blockquote> I'm planning to write a divertissement on 0-dimensional TQFT and singular cohomology. </blockquote> <p>That would be awesome!</p> <p>A tiny little bit of mostly unpolished material on this already exists on the lab, starting at <a href="https://ncatlab.org/nlab/show/geometric+model+for+elliptic+cohomology">geometric model for elliptic cohomology</a>.</p> <p>in particular there is</p> <ul> <li><a href="https://ncatlab.org/nlab/show/%281%2C1%29-dimensional+Euclidean+field+theories+and+K-theory">(1,1)-dimensional Euclidean field theories and K-theory</a></li> </ul> </div>
    • CommentRowNumber3.
    • CommentAuthordomenico_fiorenza
    • CommentTimeDec 18th 2009
    • (edited Dec 18th 2009)
    Fine! Then I can add a (0,1)-dimensional TQFT and singular cohomology subsection there (this will take at least few days), and also try to polish a bit here and there on the geometric model for elliptic cohomology entry, if that will be the case.
    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeDec 18th 2009

    Thanks, great.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeDec 18th 2009

    maybe one remark:

    please don't try to produce something perfect, only to never finish it.

    The more imperfect your entry will be, the better. The rest of us wants to have soemthing to work on, too! :-)

  2. You'll agree that writing something more imperfect than 0-dimensional TQFT would be an hard task.. :)
    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeDec 21st 2009
    This comment is invalid XHTML+MathML+SVG; displaying source. <div> <blockquote> ... <a href="https://ncatlab.org/nlab/show/0-dimensional+TQFT">0-dimensional TQFT</a> ... </blockquote> <p>Thanks! Nice.</p> <p>I just went through it and edited a bit, adding hyperlinks and headlines and a toc. Have a look to check if you are happy with what I did.</p> </div>