Mumford's Degree of Contact and Diophantine Approximations

  title={Mumford's Degree of Contact and Diophantine Approximations},
  author={Roberto Ferretti},
  journal={Compositio Mathematica},
  • R. Ferretti
  • Published 2 April 1998
  • Mathematics
  • Compositio Mathematica
The purpose of this note is to present a somewhat unexpected relation between diophantine approximations and the geometric invariant theory. The link is given by Mumford's degree of contact. We show that destabilizing flags of Chow-unstable projective varieties provide systems of diophantine approximations which are better than those given by Schmidt's subspace theorem, and we give examples of these systems. 

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