Fano's inequality is also false for three-dimensional quadric

2002/02/13 by Marat Gizatullin, Gizatullin, Marat
Computer Science · Mathematics · #14E07 #14J45 #Algebraic Geometry (math.AG) #Algebraic Geometry and Number Theory #FOS: Mathematics #Mathematics and Applications #Polynomial and algebraic computation #math.AG #msc:14E07 #msc:14J45

paper · pdf · doi:10.48550/arxiv.math/0202117

8 pages of LaTeX

arxiv created 2002/02/13 · openalex publication_date 2002/02/13 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

A birational transformation of three-dimensional quadric is constructed. The inequalities of fano are not fulfilled for this transformation.

Related

• Fano's inequality is a mistake
• Fano's inequality is false for a simple Cremona transformation of five-dimensional projective space
• On the Noether--Fano inequalities
• On canonical Fano intrinsic quadrics
• On the birational geometry of Q-Fano threefolds of large Fano index, II