Lemma 23.1.61.5F2A120794A6 Suppose $\sqrt t\, W(t)$ is bounded but does not tend to zero. There are smooth $u_ j\in \mathcal R$ converging in capacity to $g\in \mathcal R$ such that a weak cluster measure of $\nu _{W,u_ j}$ gives positive mass to the pole divisor
\[ H=\pi ^{-1}\{ [z_0:z_1:z_2]:z_0=0\} , \]
whereas $\nu _{W,g}(H)=0$.
Proof.
Use the correction chosen in the proof of theorem 23.1.56. Its plateau and its late supplement satisfy
\[ \int r^0_\eta =K\eta x_{\rm pre}+O(\eta ),\qquad \int s_\eta =O(\sqrt{\eta L})+O(\eta ),\qquad \eta x_{\rm pre}\to \ell . \]
Therefore $m_\eta \to m:=K\ell >0$. Shrink the fixed $c$ so that $m$ satisfies all the established positivity margins. On each fixed finite $x$ interval, $r_\eta $ and all its derivatives tend to zero; the late supplement escapes the interval. Thus $g_\eta $ converges smoothly there to
\[ g(x)=-m\int _{-\infty }^ x(x-s)\psi (s)\, \mathrm ds. \]
It is zero for $x\leq -2$ and equals $-m(x-\mu _\psi )$ for $x\geq -1$. The same margins give $\mu +g'>0$ and $g''+\mu (1-\mu )\geq 0$ at finite $x$. Across $H$, its extension has logarithmic singularity of coefficient $m$: a local defining function $\zeta $ gives $g=m\log |\zeta |^2+O(1)$. Its upper semicontinuous extension is $\omega $-plurisubharmonic, has supremum zero and belongs to $\mathcal R$.
The bound (23.1.58) and $F_\eta \leq C\eta $ imply that, on compact base sets away from $H$, each fixed-depth exceptional set lies in an exponentially shrinking tube about the local holomorphic zero section $w=0$. These tubes have capacity tending to zero. Indeed, on a relatively compact coordinate chart, $\log |w|^2$ is locally integrable and plurisubharmonic; the weighted Chern–Levine–Nirenberg estimate of section 5.27 bounds the relative capacity of $\{ \log |w|^2<-T\} $ by $C/T$. A finite cover and the local capacity comparison transfer this estimate to $\operatorname {Cap}_\omega $.
The corrections converge uniformly on compact base sets away from $H$, including $\xi =0$, and the supremum normalization is $O(\eta )$. Since $g$ has its logarithmic pole on $H$, the estimate (5.29.4) gives neighborhoods of $H$ with arbitrarily small capacity. Removing one such neighborhood proves $u_\eta \to g$ in capacity.
Assume $\sqrt t\, W(t)$ is bounded but does not tend to zero. Choose the preceding sequence of cores with weighted mass bounded below by $c_0>0$. The proved upper bound makes their full weighted measures uniformly finite, so a subsequence has a weak cluster measure $\nu $. For each fixed closed neighborhood $H_ r$ of $H$, all sufficiently late cores lie in $H_ r$. Portmanteau gives $\nu (H_ r)\geq c_0$; decreasing continuity of the finite measure gives $\nu (H)\geq c_0$. But $\nu _{W,g}(H)=0$ by its defining non-pluripolar truncation.
$\square$
Theorem 23.1.62.8BCBC6CB58C6 Within $\mathcal R$ the following assertions hold.
Every individual $\nu _{W,u}$ is finite if and only if $\sup _{t\gg 1}\sqrt t\, W(t)<\infty $. This is also equivalent to a uniform total-mass bound. In this case
\[ \sup _{u\in \mathcal R}\nu _{W,u}(X)\leq 12Q(W). \]
If the condition fails there is one $u\in \mathcal R$ with infinite measure.
Uniform deep tails hold if and only if $\sqrt t\, W(t)\to 0$. For all $u\in \mathcal R$ and $T\geq 0$,
\[ \nu _{W,u}(\{ -u>T\} )\leq 12Q_ T(W). \]
The inequality is understood in the extended sense.
Uniform absolute continuity relative to $\operatorname {Cap}_\omega $ holds if and only if $\sqrt t\, W(t)\to 0$.
The assignment $u\mapsto \nu _{W,u}$ is a map into finite measures and is continuous from capacity convergence in $\mathcal R$ to weak measure convergence if and only if $\sqrt t\, W(t)\to 0$. When $\sqrt t\, W(t)$ is bounded but does not tend to zero, there are smooth $u_ j\in \mathcal R$ converging in capacity to $g\in \mathcal R$, whose weighted measures have a weak cluster measure charging the pole divisor of $g$.
Proof.
The sufficient conditions are proposition 23.1.47. The necessary uniform mass and tail conditions follow from corollary 23.1.55, whose smooth potentials are invariant. If $\sqrt t\, W(t)$ is unbounded, theorem 23.1.56 disproves universal individual finiteness and prevents a map into finite measures.
For uniform absolute continuity, the concentration regions of theorem 23.1.52 lie in $\{ x\geq c_1/\eta \} $ for a fixed $c_1>0$, hence in shrinking neighborhoods of $H$. The globally defined $h_ H=\log (|z_0|^2/|z|^2)$ has supremum zero and $\omega +\mathrm{dd}^{\mathrm{c}}h_ H=\beta +[H]\geq 0$. Its sublevel estimate (5.29.4) shows that these neighborhoods have capacity tending to zero. If $\limsup _{t\to +\infty }\sqrt t\, W(t)>0$, choose the scales so that $D\eta ^{-1}W(B\eta ^{-2})$ stays bounded below. The weighted masses on these regions then violate uniform absolute continuity. Finally, lemma 23.1.61 disproves capacity-to-weak continuity whenever $\sqrt t\, W(t)$ is bounded but does not tend to zero.
$\square$
Corollary 23.1.63.E636296BB209 For a weight $W$ satisfying the assumptions of this section and agreeing for large $t$ with
\[ W_{p,a}(t)=(1+t)^{-p}[\log (\mathrm e+t)]^{-a}, \]
universal individual finiteness and uniform total-mass bounds in $\mathcal R$ hold exactly when $p>1/2$, or $p=1/2$ and $a\geq 0$. Uniform deep tails, uniform capacity absolute continuity and capacity-to-weak continuity hold exactly when $p>1/2$, or $p=1/2$ and $a>0$.
Proof.
Apply theorem 23.1.62 to $\sqrt t\, W_{p,a}(t)\sim t^{1/2-p}(\log t)^{-a}$. A smooth decreasing modification on a compact interval changes none of these conditions.
$\square$
The necessary conditions and the single infinite-measure example also apply to the class of all normalized potentials on $X$. The sufficient conditions proved here use the $U(2)$ symmetry. For the unrestricted class, proposition 13.15.9 still gives the sufficient condition $\int _0^{+\infty }(1+t)(-W'(t))\, \mathrm dt<+\infty $; its optimal damping rate remains open.
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