4 papers
Non-projective complete log canonical surfaces
Osamu Fujino, Nao Moriyama, Hiroshi Sato
We construct non-projective complete log canonical algebraic surfaces whose canonical divisors are semi-ample over an algebraically closed field of any characteristic other than th…
A note on -Gorenstein surfaces
Nao Moriyama
We construct a normal projective -Gorenstein surface over an algebraically closed field whose canonical ring is not finitely generated. Moreover, we provide a counterex…
Remarks on the minimal model theory for log surfaces in the analytic setting
Nao Moriyama
We discuss the relative log minimal model theory for log surfaces in the analytic setting. More precisely, we show that the minimal model program, the abundance theorem, and the fi…
On a vanishing theorem for surfaces
Osamu Fujino, Nao Moriyama
We propose a new formulation of a vanishing theorem for surfaces. Although this vanishing theorem follows easily from the well-known Kawamata--Viehweg vanishing theorem, it turns o…