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Semi-Normal Log Centres and Deformations of Pairs

Published online by Cambridge University Press:  19 December 2013

János Kollár*
Affiliation:
Department of Mathematics, Princeton University, Fine Hall, Washington Road, Princeton, NJ 08544-1000, USA (kollar@math.princeton.edu)
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Abstract

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We show that some of the properties of log canonical centres of a log canonical pair also hold for certain subvarieties that are close to being a log canonical centre. As a consequence, we obtain that, in working with deformations of pairs where all the coefficients of the boundary divisor are bigger than ½, embedded points never appear on the boundary divisor.

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 2014 

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