Successive minima of projective toric varieties

 
M. Sombra

 
 
  We compute the algebraic successive minima of the projective toric variety X_A associated to a finite set A \subset Z^n. As a consequence of this computation and the results of S.-W. Zhang on the distribution of small points, we derive estimates for the height of the variety X_A and of the A-resultant.

These estimates allow us to obtain an arithmetic analogue of the Kushnirenko's theorem concerning the number of solutions of a polynomial equation system. As an application of this result, we improve the previous estimates for the height of the polynomials in the sparse Nullstellensatz.
 
  Comments : 23 pp., in French.