Let $(Y,h_0)$ be a connected compact Hermitian manifold of dimension $m\geq 1$, and on $X=\mathbb P^ k\times Y$ put $H=\operatorname {pr}_1^*\kappa +\operatorname {pr}_2^*h_0$, $N=k+m$ and $V_0=\int _ Yh_0^ m$. Pull $u_\alpha $ and $F$ back to $X$, and define $E_ F^ H$ by (11.47.1) using the full family $\mathrm{PSH}(X,H)$.
Proposition 11.47.14.E4713F2FEF7D One has $E_ F^ H=\operatorname {pr}_1^*E_ F$ and
\[ \operatorname{MA}_ H(E_ F^ H)=\binom Nk\, \operatorname{MA}_\kappa (E_ F)\otimes h_0^ m, \qquad \operatorname{MA}_ H(E_ F^ H)(X)=\binom Nk V_0. \]
The pulled-back residual is globally $C^{1,1}$, and $E_ F^ H$ belongs to $\mathcal E_{\mathrm{env}}(X,H,u_\alpha )$. On each fixed product the uniform bounds and derivative stability of theorem 11.47.11 hold for these residuals.
Proof.
Every competitor restricts to a projective slice as a $\kappa $-plurisubharmonic function or as $-\infty $ identically. To check the exact lower bound when $H$ is nonclosed, choose a smooth quadratic correction $q$ with $\mathrm{dd}^{\mathrm{c}}q\geq H$ on a coordinate polydisk and let $v_\epsilon =(v+q)*\eta _\epsilon -q$ on a smaller polydisk, where $\eta _\epsilon $ is the rescaling of a fixed smooth nonnegative radial probability kernel. Radial plurisubharmonic convolutions decrease to the canonical $v+q$, and
\[ \mathrm{dd}^{\mathrm{c}}v_\epsilon \geq (\mathrm{dd}^{\mathrm{c}}q-H)*\eta _\epsilon -\mathrm{dd}^{\mathrm{c}}q \geq -H-o(1)\omega _{\mathrm{Eucl}}. \]
Restrict this smooth inequality to a fixed slice. The corrected restrictions decrease either to $-\infty $ or to a plurisubharmonic function in local $L^1$; in the latter case the background error tends to zero distributionally. Subtracting $q$ gives the exact $\kappa $ bound, and these canonical restrictions patch on the connected slice. The everywhere obstacle constraint now gives $v\leq \operatorname {pr}_1^*E_ F$ on every slice. Upper regularization preserves this bound. Conversely every base competitor lifts, since $h_0>0$, proving equality of the full envelopes.
The bounded truncations $\max (E_ F^ H,-j)$ are pullbacks. By proposition 5.28.2, lemma 5.28.4, dimensional multilinearity leaves only the term with $k$ projective factors and $m$ factor entries. Restrict to strict superlevel sets and let $j\to \infty $ to obtain the stated non-pluripolar measure and its finite mass. The residual regularity and uniform estimates pull back in a fixed smooth product atlas. Finally $E_ F^ H\geq u_\alpha -K_ F$. At $t=1$ take the stretching witness $v_1=E_ F^ H$; for $t>1$ take $v_ t=u_\alpha -tK_ F$, so that
\[ t^{-1}v_ t+(1-t^{-1})u_\alpha =u_\alpha -K_ F\leq E_ F^ H. \]
Together with ordinary domination this is definition 16.28.61, including the canonical values at the common pole.
$\square$
Example 11.47.15.1E30DC99E57B There is a nonclosed positive background on a non-Kähler fourfold for which the preceding full envelope formula and uniform residual estimates hold.
Proof.
Take $Y=(\mathbb C^2\setminus \{ 0\} )/\langle \zeta \mapsto \mathrm e\zeta \rangle $. With $s=\log |\zeta |^2$, the form $h_0=\mathrm{dd}^{\mathrm{c}}s+\mathrm ds\wedge \mathrm d^{\mathrm c}s$ is invariant under the quotient. Its two summands are positive on the tangential and radial complex directions, respectively, so it is Hermitian. Moreover $\mathrm dh_0=-\mathrm ds\wedge \mathrm{dd}^{\mathrm{c}}s\ne 0$. The Hopf surface is diffeomorphic to $S^3\times S^1$ and has odd first Betti number. Thus $X=\mathbb P^2\times Y$ is a non-Kähler fourfold with $\mathrm dH\ne 0$, and proposition 11.47.14 applies.
$\square$
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