Đề tài " The density of discriminants of quartic rings and fields "
Steiner symmetrization, one of the simplest and most powerful symmetrization
processes ever introduced in analysis, is a classical and very well-known
device, which has seen a number of remarkable applications to problems of
geometric and functional nature. Its importance stems from the fact that,
besides preserving Lebesgue measure, it acts monotonically on several geometric
and analytic quantities associated with subsets of Rn. Among these,
perimeter certainly holds a prominent position. Actually, the proof of the
isoperimetric property of the ball was the original motivation for Steiner to
introduce his symmetrization in...