ผลต่างระหว่างรุ่นของ "ผู้ใช้:Keeplearn/กระบะทราย2ExteriorAlgebra"
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บรรทัด 2:
[[File:N-vector.svg|thumb|125px|Geometric interpretation for the '''exterior product''' of ''n'' [[vector (geometry)|vector]]s ('''u''', '''v''', '''w''') to obtain an ''n''-vector ([[parallelotope]] elements), where ''n'' = [[graded algebra|grade]],<ref>{{cite book |author=R. Penrose| title=[[The Road to Reality]]| publisher= Vintage books| year=2007 | isbn=0-679-77631-1}}</ref> for ''n'' = 1, 2, 3. The "circulations" show [[Orientation (vector space)|orientation]].<ref>{{cite book|title=Gravitation|author=J.A. Wheeler, C. Misner, K.S. Thorne|publisher=W.H. Freeman & Co|year=1973|page=83|isbn=0-7167-0344-0}}</ref>]]
ในทาง[[คณิตศาสตร์]] '''
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'''พีชคณิตภายนอก''' หรือ '''พีชคณิตของกรัสส์แมน''' ตั้งชื่อตาม[[แฮร์มันน์ กรัสส์มันน์]],<ref>{{harvcoltxt|Grassmann|1844}} introduced these as ''extended'' algebras (cf. {{harvnb|Clifford|1878}}). He used the word ''äußere'' (literally translated as ''outer'', or ''exterior'') only to indicate the ''produkt'' he defined, which is nowadays conventionally called ''exterior product'', probably to distinguish it from the ''[[outer product]]'' as defined in modern [[linear algebra]].</ref> เป็นระบบพีชคณิตที่ผลลัพธ์ของมันคือ
In a precise sense, given by what is known as a [[universal property|universal construction]], the exterior algebra is the ''largest'' algebra that supports an alternating product on vectors, and can be easily defined in terms of other known objects such as [[tensor]]s. The definition of the exterior algebra makes sense for spaces not just of geometric vectors, but of other vector-like objects such as [[vector field]]s or [[function (mathematics)|functions]]. In full generality, the exterior algebra can be defined for [[module (mathematics)|modules]] over a [[commutative ring]], and for other structures of interest in [[abstract algebra]]. It is one of these more general constructions where the exterior algebra finds one of its most important applications, where it appears as the algebra of [[differential forms]] that is fundamental in areas that use [[differential geometry]]. Differential forms are mathematical objects that represent [[infinitesimal]] areas of infinitesimal parallelograms (and higher-dimensional bodies), and so can be [[integral|integrated]] over surfaces and higher dimensional [[manifold]]s in a way that generalizes the [[line integral]]s from calculus. The exterior algebra also has many algebraic properties that make it a convenient tool in algebra itself. The association of the exterior algebra to a vector space is a type of [[functor]] on vector spaces, which means that it is compatible in a certain way with linear transformations of vector spaces. The exterior algebra is one example of a [[bialgebra]], meaning that its [[dual space]] also possesses a product, and this dual product is compatible with the exterior product. This dual algebra is precisely the algebra of [[alternating multilinear form]]s on ''V'', and the pairing between the exterior algebra and its dual is given by the [[interior product]].
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