Algebraic Homotopy Classes of Rational Functions
نویسنده
چکیده
A. – Let k be a field. We compute the set [ P,P ]N of naive homotopy classes of pointed k-scheme endomorphisms of the projective line P. Our result compares well with Morel’s computation in [11] of the group [ P,P ]A1 of A-homotopy classes of pointed endomorphisms of P: the set [ P,P ]N admits an a priori monoid structure such that the canonical map [ P,P ]N → [P1,P1]A1 is a group completion.
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