Irrational Centers

Sandor Kovacs
2011 Pure and Applied Mathematics Quarterly  
Irrational centers are defined analogously to associated primes. The union of irrational centers is the locus of non-rational singularities, but irrational centers carry more information. There may be embedded irrational centers signifying more complicated singularities. Various results regarding irrational centers are proved, in particular some concerning depth estimates and the Cohen-Macaulayness of certain ideal sheaves. It is also proved that absolute irrational centers of a log canonical
more » ... f a log canonical pair are also non-klt centers. This allows applying results proved for irrational centers for non-klt centers of log canonical pairs.
doi:10.4310/pamq.2011.v7.n4.a19 fatcat:pm2afoaqszfx5mq6t6mmbcgtoi