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Compute the Kac polynomial of a quiver #15187

Open 12d81aa2-5825-4c50-9de3-ede0c21017ed opened 10 years ago

12d81aa2-5825-4c50-9de3-ede0c21017ed commented 10 years ago

Compute the number of isomorphism classes of absolutely indecomposable representations of a quiver with a given dimension vector using the Kac-Stanley formula (see page 90 of Root systems, representations of quivers and invariant theory by Victor G. Kac).

Component: combinatorics

Keywords: quiver, representation, Kac-polynomial

Work Issues: add and test examples

Author: Amritanshu Prasad

Branch/Commit: public/15187 @ bcab72f

Issue created by migration from https://trac.sagemath.org/ticket/15187

tscrim commented 10 years ago
comment:1

Hey Amri,

Here's my initial work, but something isn't correct. I think what's going wrong is when I'm trying to do the log portion... I'm still looking into it.

Best,

Travis


New commits:

45ad857Merge branch 'develop' into u/tscrim/kac_polynomial
3d2096dMerge branch 'u/tscrim/kac_polynomial' of trac.sagemath.org:sage into u/tscrim/kac_polynomial
8ec237dStarted Kac polynomials and DT-invariants.
e0362d5Merge branch 'master' into u/tscrim/kac_polynomial
e3a32fcMerge branch 'master' into u/tscrim/kac_polynomial
895db3aStarted Kac polynomials and DT-invariants.
tscrim commented 10 years ago

Commit: 45ad857

tscrim commented 10 years ago

Branch: u/tscrim/kac_polynomial

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 10 years ago

Changed commit from 45ad857 to e2ac570

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 10 years ago

Branch pushed to git repo; I updated commit sha1. New commits:

e2ac570Merge branch 'develop' into u/tscrim/kac_polynomial
fchapoton commented 8 years ago

New commits:

cec5ca2Merge branch 'u/tscrim/kac_polynomial' into 6.9.rc3
fchapoton commented 8 years ago

Changed branch from u/tscrim/kac_polynomial to public/15187

fchapoton commented 8 years ago

Changed commit from e2ac570 to cec5ca2

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 8 years ago

Changed commit from cec5ca2 to 5425bf8

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 8 years ago

Branch pushed to git repo; I updated commit sha1. New commits:

39996d6Merge branch 'public/15187' into 6.10.beta2
5425bf8trac #15187 cleanup, update, refactor, more doc
fchapoton commented 8 years ago

Description changed:

--- 
+++ 
@@ -1 +1 @@
-Compute the number of isomorphism classes of absolutely indecomposable representations of a quiver with a given dimension vector using the Kac-Stanley formula (see *Root systems, representations of quivers and invariant theory* by Victor G. Kac).
+Compute the number of isomorphism classes of absolutely indecomposable representations of a quiver with a given dimension vector using the Kac-Stanley formula (see page 90 of *Root systems, representations of quivers and invariant theory* by Victor G. Kac).
fchapoton commented 8 years ago

Work Issues: add and test examples

fchapoton commented 8 years ago

Changed keywords from quivers, representations, Kac-polynomial to quiver, representation, Kac-polynomial

7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 8 years ago

Branch pushed to git repo; I updated commit sha1. New commits:

731c2c3Merge branch 'public/15187' into 7.1.b5
bcab72ftrac #15187 adding to the module list
7ed8c4ca-6d56-4ae9-953a-41e42b4ed313 commented 8 years ago

Changed commit from 5425bf8 to bcab72f

fchapoton commented 8 years ago
comment:11

I have made a new branch at u/chapoton/15187 where I try to use the correct formulas.

But I think that the naive approach is doomed to fail, as we probably need to compute inside the tensor product of r copies of Sym.

fchapoton commented 3 years ago
comment:12

see related stuff in #31950

fchapoton commented 2 years ago
comment:13

references here : https://ask.sagemath.org/question/47448/betti-numbers-of-nakajima-quiver-varieties/

and there : https://arxiv.org/abs/0811.1569