Theorem 18.27.4.0E6CABEB995A Suppose (18.27.1) holds and put $B=\theta -\chi _\Delta $. The ordinary type of $\sigma _\Delta +q$ contains a strict $\theta $-current if and only if $B$ has a smooth strictly positive representative: $B+\mathrm{dd}^{\mathrm{c}}f>0$ for some smooth real $f$.
Theorem 18.27.40E6CABEB995A
Proof. Suppose first that $v\sim \sigma _\Delta +q$ and $\theta +\mathrm{dd}^{\mathrm{c}}v\geq \epsilon h$ with $\epsilon >0$. By lemma 18.27.2, $\nu (v,D_ j)=a_ j$. Apply lemma 5.38.1 with background $\theta -\epsilon h$ to obtain
For $\Delta =0$ this is the original strict inequality. The $L^1$ difference $v-\sigma _\Delta $ consequently has a global quasi-plurisubharmonic representative $q'$ with $B+\mathrm{dd}^{\mathrm{c}}q'\geq \epsilon h$. Off the divisor it satisfies $q'\sim q$; these inequalities extend everywhere by lemma 5.24.3. Thus $q'$ has zero point Lelong numbers, and lemma 18.27.3 gives $B+\mathrm{dd}^{\mathrm{c}}f>0$ for a smooth $f$.
Conversely, compactness gives $B+\mathrm{dd}^{\mathrm{c}}f\geq \epsilon h$ for some $\epsilon >0$. Choose $q_\delta $ in (18.27.1) with $\delta <\epsilon /2$. Then $v=\sigma _\Delta +q_\delta +f$ is in the specified ordinary type, and Poincaré–Lelong gives
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