翻訳と辞書
Words near each other
・ Quittin' Time
・ Quitting
・ Quittner
・ Quittor
・ Quitu culture
・ Quitupan
・ Quitzdorf am See
・ Quitzin Hunting Lodge
・ Quitéria River
・ Quitéro River
・ Quiun Qeshlaqi
・ Quiver
・ Quiver (comics)
・ Quiver (disambiguation)
・ Quiver (KTU album)
Quiver (mathematics)
・ Quiver (Monk album)
・ Quiver (video game)
・ Quiver Creek
・ Quiver diagram
・ Quiver Party
・ Quiver River
・ Quiver tip
・ Quiver Township, Mason County, Illinois
・ Quiver Tree Forest
・ Quiverfull
・ Quivet
・ Quivicán
・ Quivicán Municipal Museum
・ Quiviger


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Quiver (mathematics) : ウィキペディア英語版
Quiver (mathematics)
In mathematics, a quiver is a directed graph where loops and multiple arrows between two vertices are allowed, i.e. a multidigraph. They are commonly used in representation theory: a representation ''V'' of a quiver assigns a vector space ''V''(''x'') to each vertex ''x'' of the quiver and a linear map ''V''(''a'') to each arrow ''a''.
In category theory, a quiver can be understood to be an underlying structure of a category, but without identity morphisms and composition. That is, there is a forgetful functor from Cat to Quiv. Its left adjoint is a free functor which, from a quiver, makes the corresponding free category.
==Definition==

A quiver Γ consists of:
* The set ''V'' of vertices of Γ
* The set ''E'' of edges of Γ
* Two functions: ''s'': ''E'' → ''V'' giving the ''start'' or ''source'' of the edge, and another function, ''t'': ''E'' → ''V'' giving the ''target'' of the edge.
This definition is identical to that of a multidigraph.
A morphism of quivers is defined as follows. If \Gamma=(V,E,s,t) and \Gamma'=(V',E',s',t') are two quivers, then a morphism m=(m_v, m_e) of quivers consist of two functions m_v: V\to V' and m_e: E\to E' such that following diagrams commute:
:m_v \circ s = s' \circ m_e
and
:m_v \circ t = t' \circ m_e

抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)
ウィキペディアで「Quiver (mathematics)」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.