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 definitions 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 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).
    • CommentRowNumber1.
    • CommentAuthorTobyBartels
    • CommentTimeOct 25th 2009

    Todd started Schur functor. I added internal links and wrote linear category to be the target of one of them.

    • CommentRowNumber2.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 25th 2009

    Thanks, but I should say that I was in the middle of an edit when you did all that, and my submission erased your links, which I tried to reinsert. Please check: the link to "change of base" was supposed to point to an extant page, but I'm not sure which.

    • CommentRowNumber3.
    • CommentAuthorTobyBartels
    • CommentTimeOct 25th 2009

    Ah, your edit took longer than 30 minutes, so the lock timed out! And here I thought that you had cancelled it.

    • CommentRowNumber4.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 25th 2009

    Ah, I had no idea that locks time out! That's annoying, but at least now I know. I was busy trying to get the kids in bed and so on when it happened.

    • CommentRowNumber5.
    • CommentAuthorTobyBartels
    • CommentTimeOct 25th 2009

    I believe that they time out so that people can't lock a page forever if they just forget about it or their Internet connection crashes or something.

    Sometimes I'll save a draft every 15 minutes or so to prevent it.

    • CommentRowNumber6.
    • CommentAuthorGuest
    • CommentTimeOct 26th 2009
    To get around the spam filter in the minimum time, I'll drop my intended comment for Schur functor here:

    is the divided powers functor Ab --> Ab a Schur functor? The preprint arXiv:0910.2817, section 2.1 has details.
    How about the Lie functor Ab --> Ab, which is just the tensor algebra with the obvious Z-Lie structure? Same paper for details.

    David Roberts
    • CommentRowNumber7.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 26th 2009

    Thanks, David. For the time being I'm restricting to categories enriched in rational vector spaces, so for the time being let me apply the query to Vect_{fd} (finite-dimensional spaces) instead of Ab. Then yes, it looks like their paper gives formulas for the homogeneous components of these constructions as direct sums of certain classical S_\lambda's.

    • CommentRowNumber8.
    • CommentAuthorbwebster
    • CommentTimeOct 27th 2009
    I added a stubby part about using arbitrary representations of S_n.
    • CommentRowNumber9.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 27th 2009

    Thanks, Ben. I added a small and maybe slightly cryptic comment, to be followed up on later.

    • CommentRowNumber10.
    • CommentAuthorbwebster
    • CommentTimeOct 28th 2009

    I also created a stub on Specht modules, which should be key for defining analogues of Schur functors for all abelian monoidal categories.