Yujiro Kawamata

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Yujiro Kawamata
NationalityFlag of Japan.svg  Japanese
Alma mater University of Tokyo
Known for Kawamata-Viehweg vanishing theorem
Kawamata log terminal (klt) singularities
Scientific career
Fields Mathematics
Institutions University of Tokyo
Doctoral advisor Shigeru Iitaka

Yujiro Kawamata (born 1952) is a Japanese mathematician working in algebraic geometry.

Contents

Career

Kawamata completed the master's course at the University of Tokyo in 1977. He was an Assistant at the University of Mannheim from 1977 to 1979 and a Miller Fellow at the University of California, Berkeley from 1981 to 1983. Kawamata is now a professor at the University of Tokyo. He won the Mathematical Society of Japan Autumn award (1988) and the Japan Academy of Sciences award (1990) for his work in algebraic geometry.

Research

Kawamata was involved in the development of the minimal model program in the 1980s. The program aims to show that every algebraic variety is birational to one of an especially simple type: either a minimal model or a Fano fiber space. The Kawamata-Viehweg vanishing theorem, strengthening the Kodaira vanishing theorem, is a method. Building on that, Kawamata proved the basepoint-free theorem. The cone theorem and contraction theorem, central results in the theory, are the result of a joint effort by Kawamata, Kollár, Mori, Reid, and Shokurov. [1]

After Mori proved the existence of minimal models in dimension 3 in 1988, Kawamata and Miyaoka clarified the structure of minimal models by proving the abundance conjecture in dimension 3. [2] Kawamata used analytic methods in Hodge theory to prove the Iitaka conjecture over a base of dimension 1. [3]

More recently, a series of papers by Kawamata related the derived category of coherent sheaves on an algebraic variety to geometric properties in the spirit of minimal model theory. [4]

Notes

  1. Y. Kawamata, K. Matsuda, and K. Matsuki. Introduction to the minimal model program. Algebraic Geometry, Sendai 1985. North-Holland (1987), 283-360.
  2. Y. Kawamata. Abundance theorem for minimal threefolds. Invent. Math. 108 (1992), 229-246.
  3. Y. Kawamata. Kodaira dimension of algebraic fiber spaces over curves. Invent. Math. 66 (1982), 57-71.
  4. Y. Kawamata. D-equivalence and K-equivalence. J. Diff. Geom. 61 (2002), 147-171.

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References