# Mumford's Degree of Contact and Diophantine Approximations

@article{Ferretti2000MumfordsDO,
title={Mumford's Degree of Contact and Diophantine Approximations},
author={Roberto Ferretti},
journal={Compositio Mathematica},
year={2000},
volume={121},
pages={247-262}
}
• 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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