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تسجيل مستخدم جديدOn a generalized canonical bundle formula for generically finite morphisms
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We prove a canonical bundle formula for generically finite morphisms in the setting of generalized pairs (with $mathbb{R}$-coefficients). This complements Filipazzis canonical bundle formula for morphisms with connected fibres. It is then applied to obtain a subadjunction formula for log canonical centers of generalized pairs. As another application, we show that the image of an anti-nef log canonical generalized pair has the structure of a numerically trivial log canonical generalized pair. This readily implies a result of Chen--Zhang. Along the way we prove that the Shokurov type convex sets for anti-nef log canonical divisors are indeed rational polyhedral sets.
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