Lemma 10.25.9.BCA9F26FE4F4 For $C>0$ sufficiently large, put $\theta =C\omega _0$. For either profile $v$ in (10.25.8), the function $u=\pi _1^*v$ belongs to $\mathrm{PSH}(X,\theta )$, the form $T=\theta +\mathrm{dd}^{\mathrm{c}}u$ is smooth and positive on $X\setminus D$, and
\[ \int _ X\mathrm{MA}_\theta (u)=\int _ X\theta ^ n. \]
The same $C$ may be used for the two fixed profiles. The bounded profile has minimal ordinary singularities; the profile $v_{\mathrm c}$ does not.
Proof.
For a twice differentiable function $G$ of $L=-\log |z|^2$, differentiation away from zero gives
\[ \frac{\partial ^2G(L)}{\partial z\partial \bar z} =\frac{G''(L)}{|z|^2}. \]
On the inner disk this yields
F60812366089
10.25.10
\begin{equation} (v_{\mathrm c})_{z\bar z}=\frac{A}{|z|^2L^2},\qquad (v_\beta )_{z\bar z}=\frac{\eta \beta (\beta +1)}{|z|^2L^{\beta +2}}. \end{equation}
Both densities are integrable at zero. Both profiles are locally integrable, and their distributional Hessians have no additional atom at zero. To see this, integrate twice by parts outside $\{ |z|=\varepsilon \} $: the boundary terms against a smooth test function are bounded by constant multiples of $\varepsilon |G(-\log \varepsilon ^2)|$ and $|G'(-\log \varepsilon ^2)|$, and both tend to zero for the two profiles. Thus (10.25.10) holds in the sense of distributions across the center. On the cutoff annulus all derivatives are bounded. Hence, for a sufficiently large common $C$,
\[ \alpha _ v=C\omega _ E+\mathrm{dd}^{\mathrm{c}}v \]
is a positive measure, smooth and strictly positive away from zero, with no atom at zero. Pairing $\mathrm{dd}^{\mathrm{c}}v$ with the constant test function gives $\int _ E\alpha _ v=C\int _ E\omega _ E$.
Let $Y=E^{n-1}$, let $\pi _ Y:X\to Y$ be the projection onto the remaining factors, and let $\theta _ Y$ be $C$ times the sum of the $n-1$ flat forms of $Y$. On $X\setminus D$ the smooth wedge product is
\[ T^ n=n\, \pi _1^*\alpha _ v\wedge \pi _ Y^*\theta _ Y^{n-1}; \]
for $n=1$ this means just $\alpha _ v$, with $Y$ a point. The right side defines a finite product measure on $X$ that gives $D$ zero mass. By theorem 13.14.3, the non-pluripolar measure agrees with this product off $D$ and gives the pluripolar set $D$ zero mass, so the two global measures are equal. Integrating the product proves the full-mass identity. Since $\theta >0$, its envelope is $V_\theta =0$ (section 5.40). The bounded profile therefore has minimal ordinary singularities, whereas $v_{\mathrm c}$ is not bounded below by $0$ minus a constant.
$\square$
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