Proposition 10.31.19.0BEB0F48780F Let $\nu $ be a non-pluripolar probability measure with $A_\theta (\nu )<\infty $, and let $\nu _ j$ be its smooth approximations defined by (5.44.11). Fix a constant $C>0$ and let $v_ j,v\in \mathrm{PSH}(X,\theta )$ satisfy
\[ v_ j\sim V,\qquad \sup _ Xv_ j=0,\qquad \mu _{v_ j}\leq C\nu _ j, \qquad v_ j\longrightarrow v\text{ in }L^1(X). \]
Then $v\in \mathcal E_ V$, the convergence also holds in $L^1(\nu )$ and in capacity, and
\[ \mu _{v_ j}\rightharpoonup \mu _ v. \]
Proof.
The limit $v$ is not identically $-\infty $ and satisfies $\sup _ Xv=0$, and $v_ j,v\leq V\leq 0$. By lemma 5.44.12, $\sup _ jA_\theta (\nu _ j)<\infty $, which gives the uniform estimate
CCD1547654BD
10.31.20
\begin{equation} \int _ X(-v_ j)\, \mu _{v_ j} \leq C\int _ X(-v_ j)\, \mathrm{d}\nu _ j\leq C'. \end{equation}
In particular the relative first moments $\int _ X(V-v_ j)\mu _{v_ j}$ are bounded, and proposition 10.31.8, with fixed reference $w=V$, puts $v$ in $\mathcal E_ V$.
By proposition 10.31.15, applied to the fixed measure $\nu $, the $v_ j$ are uniformly integrable with respect to $\nu $. For each fixed $T$, the bounded functions $\max (v_ j,-T)$ have a common lower curvature bound in a Hermitian background $\Omega \geq \theta $ and converge in $L^1$ for smooth volume to $\max (v,-T)$; hence lemma 5.44.2 gives their convergence in $L^1(\nu )$. These truncations need not be $\theta $-plurisubharmonic; they are used only in the larger Hermitian background. Uniform integrability, followed by $T\to \infty $, gives $v_ j\to v$ in $L^1(\nu )$, and the limit is integrable because $A_\theta (\nu )<\infty $.
The smoothing lemma, in the form (5.44.13), now yields
\[ \int _ X|v_ j-v|\, \mu _{v_ j} \leq C\int _ X|v_ j-v|\, \mathrm{d}\nu _ j\longrightarrow 0. \]
Therefore the self-measure convergence theorem theorem 10.31.11 gives convergence in capacity. Finally, (10.31.20) gives the sublevel estimate
\[ \sup _ j\mu _{v_ j}(\{ v_ j\leq -T\} )\leq C'/T, \]
and the masses of the $\mu _{v_ j}$ are bounded by $M_ V$. The tail criterion theorem 13.15.23 therefore gives the asserted weak convergence.
$\square$
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