Proposition 5.40.10.B986B6AE211B The envelope $G_ m$ is given by
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5.40.11
\begin{equation} G_ m(\zeta ,w)=m\log \frac{|\zeta |^2}{1-|w|^2}. \end{equation}
It is plurisubharmonic and continuous on $B$ with values in $[-\infty ,0)$. The finite part $G_ m-m\log |\zeta |^2$, first defined off $D$, extends smoothly across $D$ as the plurisubharmonic function
\[ H_ m(w)=-m\log (1-|w|^2). \]
Proof.
The function $-\log (1-|w|^2)$ is smooth and plurisubharmonic on $|w|<1$: its complex Hessian is
\[ \left(\frac{\delta _{jk}}{1-|w|^2} +\frac{\overline w_ jw_ k}{(1-|w|^2)^2}\right)_{j,k}. \]
Thus the right-hand side of (5.40.11) is plurisubharmonic; it is negative on $B$ and satisfies the pole condition, so it is a competitor. For the reverse inequality, fix a competitor $u$ and a point $w$ with $|w|<1$. The restriction $u(\cdot ,w)$ is either identically $-\infty $ or subharmonic on the disk of radius $R=(1-|w|^2)^{1/2}$. In the latter case, $u(\zeta ,w)-m\log |\zeta |^2$ is subharmonic on the punctured disk and, by the pole condition, bounded above near zero, so it extends as a subharmonic function across zero.
Since $u\leq 0$, this extension is at most $-m\log r^2$ on every circle $|\zeta |=r<R$. The maximum principle and then $r\uparrow R$ give
\[ u(\zeta ,w)\leq m\log \frac{|\zeta |^2}{R^2}. \]
On $D$ both sides are $-\infty $. Taking the supremum over $u$ proves the formula. Near a point of $D$, the function $H_ m$ is bounded and the logarithmic term tends to $-\infty $, which proves continuity there as an extended-real function.
$\square$
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