6533b85bfe1ef96bd12bb6fc

RESEARCH PRODUCT

Rationally integrable vector fields and rational additive group actions

Alvaro LiendoAdrien Dubouloz

subject

Integrable systemRationally integrable derivationsGeneral Mathematics010102 general mathematics05 social sciencesLocally nilpotentAlgebraic variety01 natural sciencesLocally nilpotent derivations[ MATH.MATH-AG ] Mathematics [math]/Algebraic Geometry [math.AG]AlgebraHomogeneousRational additive group actions0502 economics and businessVector fieldAffine transformation[MATH.MATH-AG]Mathematics [math]/Algebraic Geometry [math.AG]050207 economics0101 mathematicsInvariant (mathematics)MSC: 14E07 14L30 14M25 14R20Additive groupMathematics

description

International audience; We characterize rational actions of the additive group on algebraic varieties defined over a field of characteristic zero in terms of a suitable integrability property of their associated velocity vector fields. This extends the classical correspondence between regular actions of the additive group on affine algebraic varieties and the so-called locally nilpotent derivations of their coordinate rings. Our results lead in particular to a complete characterization of regular additive group actions on semi-affine varieties in terms of their associated vector fields. Among other applications, we review properties of the rational counterpart of the Makar-Limanov invariant for affine varieties and describe the structure of rational homogeneous additive group actions on toric varieties.

10.1142/s0129167x16500609https://hal-univ-bourgogne.archives-ouvertes.fr/hal-01407992