Abstract
AbstractLet $$(X,\Delta )$$
(
X
,
Δ
)
be a projective, $${{\mathbb {Q}}}$$
Q
-factorial log canonical pair and let L be a pseudoeffective $${{\mathbb {Q}}}$$
Q
-divisor on X such that $$K_X + \Delta + L$$
K
X
+
Δ
+
L
is pseudoeffective. Is there an effective $${{\mathbb {Q}}}$$
Q
-divisor M on X such that $$K_X + \Delta + L$$
K
X
+
Δ
+
L
is numerically equivalent to M? We are not aware of any counterexamples, but the answer is not completely clear even in the case of surfaces.
Funder
Università degli Studi di Trento
Publisher
Springer Science and Business Media LLC
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