{ "id": "2008.11304", "version": "v1", "published": "2020-08-25T23:13:11.000Z", "updated": "2020-08-25T23:13:11.000Z", "title": "On quiver representations over $\\mathbb{F}_1$", "authors": [ "Jaiung Jun", "Alex Sistko" ], "categories": [ "math.RT", "math.CO" ], "abstract": "We study the category $\\textrm{Rep}(Q,\\mathbb{F}_1)$ of representations of a quiver $Q$ over \"the field with one element\", denoted by $\\mathbb{F}_1$, and the Hall algebra of $\\textrm{Rep}(Q,\\mathbb{F}_1)$. Representations of $Q$ over $\\mathbb{F}_1$ often reflect combinatorics of those over $\\mathbb{F}_q$, but show some subtleties - for example, we prove that a connected quiver $Q$ is of finite type over $\\mathbb{F}_1$ if and only if $Q$ is a tree. Then, to each representation $\\mathbb{V}$ of $Q$ over $\\mathbb{F}_1$, we associate a combinatorial gadget $\\Gamma_\\mathbb{V}$, which we call a colored quiver, possessing the same information as $\\mathbb{V}$. This allows us to translate representations over $\\mathbb{F}_1$ purely in terms of combinatorics of associated colored quivers. We also explore the growth of indecomposable representations of $Q$ over $\\mathbb{F}_1$ searching for the tame-wild dichotomy over $\\mathbb{F}_1$ - this also shows a similar tame-wild dichotomy over a field, but with some subtle differences. Finally, we link the Hall algebra of the category of nilpotent representations of an $n$-loop quiver over $\\mathbb{F}_1$ with the Hopf algebra of skew shapes introduced by Szczesny.", "revisions": [ { "version": "v1", "updated": "2020-08-25T23:13:11.000Z" } ], "analyses": { "subjects": [ "16G20", "05E10", "16G60", "17B35" ], "keywords": [ "quiver representations", "hall algebra", "colored quiver", "similar tame-wild dichotomy", "translate representations" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }