Título:
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On integral quadratic forms having commensurable groups of automorphisms
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Autores:
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Montesinos Amilibia, José María
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Tipo de documento:
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texto impreso
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Editorial:
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Hiroshima University. Faculty of Science, 2013
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Dimensiones:
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application/pdf
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Nota general:
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info:eu-repo/semantics/openAccess
info:eu-repo/semantics/openAccess
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Idiomas:
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Palabras clave:
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Estado = Publicado
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Materia = Ciencias: Matemáticas: Topología
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Tipo = Artículo
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Resumen:
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We introduce two notions of equivalence for rational quadratic forms. Two n-ary rational quadratic forms are commensurable if they possess commensurable groups of automorphisms up to isometry. Two n-ary rational quadratic forms F and G are projectivelly equivalent if there are nonzero rational numbers r and s such that rF and sG are rationally equivalent. It is shown that if F\ and G\ have Sylvester signature {?,+,+,...,+} then F\ and G\ are commensurable if and only if they are projectivelly equivalent. The main objective of this paper is to obtain a complete system of (computable) numerical invariants of rational n-ary quadratic forms up to projective equivalence. These invariants are a variation of Conway's p-excesses. Here the cases n odd and n even are surprisingly different. The paper ends with some examples
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En línea:
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https://eprints.ucm.es/id/eprint/29194/1/1389102581
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