% !TEX program = pdflatex
%=====================================================================
% X-G.tex
%
% Standalone source for pdfLaTeX.
%
% Build twice:
%   pdflatex -interaction=nonstopmode -halt-on-error X-G.tex
%   pdflatex -interaction=nonstopmode -halt-on-error X-G.tex
%
% Honest scope:
%   The normalized free BRST multiplet is constructed.
%   The switched-matter breaking is evaluated.
%   An exact source-preserving variational upgrade of X-F is
%   obstructed by an explicit pairing on free metric solutions.
%   The one-loop graph inventory is proved under stated conventions.
%   The local fish extension is constructed by the finite-scaling-
%   degree theorem.
%   A scalar model of the nonlocal mixed contraction is audited
%   microlocally. Failure of the sufficient product criterion is
%   NOT called nonexistence.
%   The requested one-loop background identity is conditional on
%   construction of its remaining operations.
%
% Corrections and distinctions:
%   - Retain P_gr=-(1/4) P Box and Delta_R=-4 P E_0^R.
%   - With s bar c=b, the fermion bar c(C-b) gives b=C/2.
%   - Independent b gives off-shell nilpotence. Eliminated b does not.
%   - Source switching is not density switching.
%   - A failed wavefront product criterion is not a no-go theorem.
%   - Bare and scalar-completed observable coefficients must not both
%     be fed through the scalar Moller map.
%   - The two mixed contraction graphs exhaust the non-tadpole
%     kappa^2 hbar sector only in the declared graph convention.
%   - Background-dependent one-point graphs require another vertex
%     and first feed the relational scalar at kappa^3 in that convention.
%   - General finite quantum counterterms are not classified by leg
%     counting alone.
%   - The first scalar slot of the completed D_1 kernel is not confined
%     to supp f. Its correct compact bound is supplied below.
%   - A constraint commutator proportional to hbar does not imply
%     1 belongs to an ideal over C[[hbar]] without inverting hbar.
%
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%   No pdflatex execution, proof-assistant check, independent referee
%   review, or journal acceptance is asserted.
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\documentclass[11pt,a4paper]{article}

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\DeclareMathOperator{\tr}{tr}
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\newcommand{\R}{\mathbb R}
\newcommand{\C}{\mathbb C}
\newcommand{\dd}{\,\mathrm d}
\newcommand{\eps}{\varepsilon}
\newcommand{\Lie}{\mathcal L}
\newcommand{\sig}{\sigma_\eps}
\newcommand{\PP}{\mathcal P}
\newcommand{\Pm}{P_m}
\newcommand{\Pgr}{P_{\mathrm{gr}}}
\newcommand{\Glin}{G_{\mathrm{lin}}}
\newcommand{\Gtwo}{\mathcal G_2}
\newcommand{\Qop}{\mathcal Q}
\newcommand{\Fop}{\mathcal F}
\newcommand{\ER}{\mathsf E_0^{\mathrm R}}
\newcommand{\EA}{\mathsf E_0^{\mathrm A}}
\newcommand{\ERm}{\mathsf E_m^{\mathrm R}}
\newcommand{\EAm}{\mathsf E_m^{\mathrm A}}
\newcommand{\DR}{\Delta_{\mathrm R}^{\mathrm{gr}}}
\newcommand{\DA}{\Delta_{\mathrm A}^{\mathrm{gr}}}
\newcommand{\ga}{\mathfrak g_U}
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\newcommand{\scopebox}[2]{%
  \par\medskip\noindent
  \fbox{\begin{minipage}{%
    \dimexpr\linewidth-2\fboxsep-2\fboxrule\relax}
    \textbf{#1}\par\smallskip #2
  \end{minipage}}
  \par\medskip
}

\title{\textbf{Landmark X-G}\\[0.4em]
The normalized BRST multiplet and the one-loop background gate:\\
proved compatibility conditions, an exact-upgrade obstruction,\\
and the remaining nonlocal extension problem}
\author{Ngo Cheung}
\date{}

\usepackage{tikz}
\begin{document}
\maketitle

\begin{abstract}
We examine the proposed one-loop continuation of the fixed-regulator
relational scalar of Landmarks X-E and X-F. The graviton normalization
is retained:
$P_{\mathrm{gr}}=-\frac14\mathcal P\Box$ and
$\Delta_{\mathrm R}^{\mathrm{gr}}
=-4\mathcal P\mathsf E_0^{\mathrm R}$.
The fermion $\int\bar c(C-b)$ constructs the corresponding free
auxiliary--ghost multiplet. It gives $b=C[h]/2$, the required
Feynman-weight gauge fixing, and the ghost term $-\bar c\Box c$.
The independent auxiliary field makes the free differential
nilpotent off shell. Its Green matrix and compatibility with the
causal field algebra are proved.

Two obstacles must be distinguished. The switched scalar action
has an explicitly evaluated gauge-breaking coefficient. Separately,
X-F multiplies gravitational sources by the ramp after variation.
An exact variational upgrade retaining that field response on all
allowed backgrounds is impossible: a compact pure-gauge background
in the ramp yields a nonzero reciprocity pairing on genuine free
metric solutions. This obstruction is classical and cannot be
cancelled by a positive-quantum-order counterterm.

Under a stated Wick graph convention, two non-tadpole contraction
graphs exhaust the $\kappa^2\hbar$ sector. Their coefficients contain
no classical background. This proves a conditional background-identity
statement, not existence of the complete observable. The local
scalar--graviton fish admits finite-scaling-degree extensions.
A scalar model of the nonlocal coordinate contraction has a
null-collinear exceptional set for the sufficient wavefront product
criterion. Failure of that criterion is not called nonexistence.
The required full retarded product is not supplied by local covariance
alone.

The free BRST construction and the exact-upgrade obstruction are
released. An unconditional renormalized one-loop background identity
for the unchanged X-F prescription is not claimed.
\end{abstract}

\begin{figure}[ht]
\centering
\begin{tikzpicture}[x=1cm,y=1cm]
\node[draw,rounded corners,align=center,text width=3.15cm,font=\small,inner sep=3pt] (a) at (0,0) {Free graded multiplet};
\node[draw,rounded corners,align=center,text width=3.15cm,font=\small,inner sep=3pt] (b) at (5,0) {Gauge fermion and Green operators};
\node[draw,rounded corners,align=center,text width=3.15cm,font=\small,inner sep=3pt] (c) at (10,0) {Interacting quantum theory};
\node[draw,dashed,rounded corners,align=center,text width=9.6cm,font=\small,inner sep=3pt] (s) at (5,-2.35) {Free-shell data are not an interacting completion.};
\draw[->] (a) -- (b);
\draw[->] (b) -- (c);
\draw[->] (b) -- (s);
\end{tikzpicture}
\caption{The free multiplet is not the interacting theory. The three boxes name objects this manuscript keeps separate. The dashed box is the stated stop. Not a proof, and not an admission of a quantum coefficient.}
\label{fig:scope-X-G}
\end{figure}

\begin{figure}[ht]
\centering
\begin{tikzpicture}[x=1cm,y=1cm]
\node[draw,rounded corners,align=center,text width=4.3cm,font=\small,inner sep=3pt] (a) at (0,0) {Free graded multiplet};
\node[draw,rounded corners,align=center,text width=4.3cm,font=\small,inner sep=3pt] (b) at (6.4,0) {Interacting quantum theory};
\node[draw,dashed,rounded corners,align=center,text width=9.6cm,font=\small,inner sep=3pt] (s) at (3.2,-2.35) {Free-shell data are not an interacting completion.};
\draw[->] (a) -- (s);
\draw[->] (b) -- (s);
\end{tikzpicture}
\caption{The free multiplet is not the interacting theory. The boxes name objects this manuscript keeps separate. The dashed box is the stated stop. Not a proof, and not an admission of a quantum coefficient.}
\label{fig:split-X-G}
\end{figure}

\begin{figure}[ht]
\centering
\begin{tikzpicture}[x=1cm,y=1cm]
\node[draw,rounded corners,align=center,text width=7.2cm,font=\small,inner sep=3pt] (a) at (0,0) {Free graded multiplet};
\node[draw,rounded corners,align=center,text width=7.2cm,font=\small,inner sep=3pt] (b) at (0,-1.7) {Gauge fermion and Green operators};
\node[draw,rounded corners,align=center,text width=7.2cm,font=\small,inner sep=3pt] (c) at (0,-3.4) {Interacting quantum theory};
\node[draw,dashed,rounded corners,align=center,text width=7.2cm,font=\small,inner sep=3pt] (s) at (0,-5.2) {Free-shell data are not an interacting completion.};
\draw[->] (a) -- (b);
\draw[->] (b) -- (c);
\draw[->] (c) -- (s);
\end{tikzpicture}
\caption{Reading downward is not a transfer. The boxes name objects this manuscript keeps separate. The dashed box is the stated stop. Not a proof, and not an admission of a quantum coefficient.}
\label{fig:chain-X-G}
\end{figure}

\begin{figure}[ht]
\centering
\begin{tikzpicture}[x=1cm,y=1cm]
\node[draw,rounded corners,align=center,text width=4.2cm,font=\small,inner sep=3pt] (a) at (0,0) {Free graded multiplet};
\node[align=center,font=\small] (m) at (5.2,0) {not the same object};
\node[draw,rounded corners,align=center,text width=4.2cm,font=\small,inner sep=3pt] (b) at (10.4,0) {Interacting quantum theory};
\node[draw,dashed,rounded corners,align=center,text width=9.6cm,font=\small,inner sep=3pt] (s) at (5.2,-2.35) {Gauge fermion and Green operators. Free-shell data are not an interacting completion.};
\draw (a) -- (m);
\draw (m) -- (b);
\draw[->] (m) -- (s);
\end{tikzpicture}
\caption{Free graded multiplet is not Interacting quantum theory. The boxes name objects this manuscript keeps separate. The dashed box is the stated stop. Not a proof, and not an admission of a quantum coefficient.}
\label{fig:pair-X-G}
\end{figure}

\begin{figure}[ht]
\centering
\begin{tikzpicture}[x=1cm,y=1cm]
\node[draw,rounded corners,align=center,text width=3.15cm,font=\small,inner sep=3pt] (a) at (0,0) {Named: Free graded multiplet};
\node[draw,rounded corners,align=center,text width=3.15cm,font=\small,inner sep=3pt] (b) at (5,0) {Used here: Gauge fermion and Green operators};
\node[draw,rounded corners,align=center,text width=3.15cm,font=\small,inner sep=3pt] (c) at (10,0) {Not claimed: Interacting quantum theory};
\node[draw,dashed,rounded corners,align=center,text width=9.6cm,font=\small,inner sep=3pt] (s) at (5,-2.5) {Free-shell data are not an interacting completion.};
\draw[->] (a) -- (b);
\draw[->] (b) -- (c);
\draw[->] (b) -- (s);
\end{tikzpicture}
\caption{Three statuses stay separate. The boxes name objects this manuscript keeps separate. The dashed box is the stated stop. Not a proof, and not an admission of a quantum coefficient.}
\label{fig:gate-X-G}
\end{figure}

Figure~\ref{fig:split-X-G} records one view of the same separation. Figure~\ref{fig:chain-X-G} records one view of the same separation. Figure~\ref{fig:pair-X-G} records one view of the same separation. Figure~\ref{fig:gate-X-G} records one view of the same separation. The drawings add no hypothesis.


Figure~\ref{fig:scope-X-G} records that separation.
The drawing adds no hypothesis.



\scopebox{Release and quantifiers}{%
\textbf{Constructed:} the free graded multiplet, one gauge fermion,
its Green operators, the free differential, the natural background
ghost operator, the switched-matter breaking, and the conditional
graph inventory.

\smallskip
\textbf{Proved obstructed:} a variational/Bogoliubov upgrade whose
classical metric field map agrees exactly with X-F's source-switched
mixed map for every allowed background and free metric input.

\smallskip
\textbf{Unresolved:} the complete nonlocal one-loop retarded product
and an unconditional one-loop background-identity theorem for the
requested prescription.

\smallskip
These statements have different quantifiers. The obstruction is
not a universal no-go for perturbative gravity, nor a disproof of
X-F's direct polynomial plateau identity.}

\tableofcontents

%=====================================================================
\section{Scope and the inference that needs justification}
\label{sec:scope}
%=====================================================================

X-F constructs three fixed-width tree symbols and proves their
direct background identity through $\kappa^2$ at classical order
\cite{XF}. It also states that its gravitational switch acts on
sources, not on action densities. The latter distinction matters
when a quantum retarded map is requested.

The proposed continuation contains three logically separate tasks:
\[
 \begin{gathered}
 \text{construct a free graded carrier},\\
 \text{specify a variational interacting retarded map},\\
 \text{construct and normalize its nonlocal one-loop insertion}.
 \end{gathered}
\]
A tree kernel's admission proves none of the later tasks by itself.

Local covariance of renormalized products is also different from
comparison of two interacting splittings with the free input fields
held fixed. The latter comparison requires an explicit quantum
transport or perturbative-agreement statement. The additional
normalization conditions in \cite{HW}, and the separate background
transport analysis in \cite{TTZ}, illustrate this distinction.
Neither paper is used as an automatic completion theorem for the
present switched nonlocal observable.

We give complete proofs of the finite algebraic and classical
compatibility statements below. Conditional quantum statements
are labelled as such.

\begin{definition}[Exact source-preserving variational upgrade]
\label{def:upgrade}
An exact source-preserving upgrade of X-F consists of:
\begin{enumerate}[label=\textup{(\alph*)}]
\item its frozen free metric operator and causal relations;
\item an even interaction functional with symmetric bosonic
second variation, after elimination of the algebraic auxiliary field;
\item a classical retarded metric field map agreeing with X-F's
mixed response on every smooth free metric solution and every
allowed smooth classical background;
\item quantum corrections containing only nonnegative powers
of $\hbar$.
\end{enumerate}
Agreement in (c) is equality of the field map, equivalently equality
after every compact smooth linear metric smearing. It is stronger
than agreement of one selected relational observable.
\end{definition}

This definition makes precise one natural meaning of a
``Bogoliubov completion of X-F''. Its failure does not exclude
a weaker prescription assigning selected polynomial symbols
to an algebra, or a new density-switched theory.

%=====================================================================
\section{Frozen conventions and a support correction}
\label{sec:frozen}
%=====================================================================

\subsection{Geometry, switches, and tensor types}

Retain
\[
 M=\R^4,\qquad
 \eta=\operatorname{diag}(1,-1,-1,-1),\qquad
 \Box=\partial_t^2-\Delta,\qquad
 \Pm=\Box+m^2,\quad m\geq0.
\]
Fix the X-E/X-F observation and scalar switch
\[
 f\in C_c^\infty((0,T)\times\R^3;\R),\qquad
 g\in C_c^\infty((0,T)\times\R^3;[0,1]).
\]
Let $U$ be relatively compact with
\[
 \overline U\subset P_g:=\Int\{g=1\},\qquad
 \ga=C_c^\infty(U;TM).
\]
Write $\Kf=\supp f$. The separation condition is
\begin{equation}
 \Kf\cup\supp g\cup\overline U
 \subset\{2\delta<t<T\},\qquad 0<\eps<\delta.
 \label{eq:separation}
\end{equation}
The ramp $\sig(t)$ is smooth, zero for $t\leq0$, and one
for $t\geq\eps$. Monotonicity is not needed for the obstruction.

The backgrounds $\hcl,\kcl$ remain arbitrary smooth off-shell
tensors. In particular, \eqref{eq:separation} does not require
them to vanish in $0<t<\eps$.

Metrics and metric fluctuations are covariant symmetric tensors.
Their Euler derivatives are contravariant tensor densities.
The Lie derivative on either side of an operator acts in the
appropriate type.

For a vector field $\xi$ define
\[
 (K\xi)_{\mu\nu}
 =(\Lie_\xi\eta)_{\mu\nu}
 =\partial_\mu\xi_\nu+\partial_\nu\xi_\mu.
\]
The plateau transformation is the inherited two-jet rule
\begin{equation}
 \hcl'=\hcl+K\xi,\qquad
 \kcl'=\kcl+\Lie_\xi\hcl+K\zeta+\tfrac12\Lie_\xi K\xi,
 \qquad \xi,\zeta\in\ga.
 \label{eq:twojet}
\end{equation}

\subsection{The signed free operators}

Put
\[
 \PP u=u-\tfrac12\eta\tr_\eta u,\qquad
 C^\mu[u]=\partial_\nu(\PP u)^{\nu\mu}.
\]
Then
\[
 \PP^2=\id,\qquad CK=\Box.
\]
The formal adjoint of $C$ is
\begin{equation}
 (C^*v)_{\mu\nu}
 =-\partial_{(\mu}v_{\nu)}
       +\tfrac12\eta_{\mu\nu}\partial_\rho v^\rho
 =-\tfrac12(\PP Kv)_{\mu\nu}.
 \label{eq:Cstar}
\end{equation}
Parentheses include the factor $1/2$.

Let $A=\frac12\Glin$. The identities copied from X-E are
\begin{equation}
 A+\tfrac12C^*C=\Pgr=-\tfrac14\PP\Box,\qquad AK=0.
 \label{eq:P}
\end{equation}
The metric Green operators are
\begin{equation}
 \DR=-4\PP\ER,\qquad \DA=-4\PP\EA.
 \label{eq:DR}
\end{equation}
Thus the metric equation is equivalent, through a constant
invertible fibre map, to a normally hyperbolic equation.
We do not change its coefficient to $+4$.

The scalar action Hessian is $-\Pm$, with retarded inverse
$-\ERm$. Its equation inverse is $\ERm$. These two uses
must not be conflated.

\subsection{The mixed operator retained from X-F}

For the background de Donder gauge,
\[
 \Qop[\eta+\kappa w]
 =\Pgr+\kappa Q_w+O(\kappa^2),
 \qquad Q_w:=\Qop^{(1)}[w].
\]
The unswitched $Q_w$ is the second variation of a quadratic
background action and is formally self-adjoint.

Naturality supplies
\begin{equation}
 Q_{K\xi}u
 =\Lie_\xi(\Pgr u)-\Pgr(\Lie_\xi u).
 \label{eq:commutator}
\end{equation}
This local identity holds for all smooth $\xi$, not only
$\xi\in\ga$.

X-F's mixed source prescription is
\begin{equation}
 k_{\mathrm{mix}}[w;u]
 =-\DR(\sig Q_wu).
 \label{eq:mixed}
\end{equation}
It is \eqref{eq:mixed}, rather than a silently density-switched
replacement, that is tested in Section~\ref{sec:obstruction}.

\subsection{The first scalar slot of the completed kernel}

The support assertion for $D_1$ in X-F requires correction.
Its scalar completion contains
$-\mathsf L_{1,g}[u]\EAm f$, whose support need not be
contained in $\Kf$.

Define the compact sets
\begin{equation}
 \Of=\Kf\cup\bigl(\supp g\cap J^-(\Kf)\bigr),\qquad
 \Cf=J^-(\Kf)\cap\{t\geq0\}.
 \label{eq:correctsets}
\end{equation}

\begin{lemma}[Corrected completed-kernel support]
\label{lem:Dsupport}
The first completed test
\[
 d_1[u]=\partial_\mu(fX_1^\mu[u])
                  -\mathsf L_{1,g}[u]\EAm f
\]
has a compact kernel $D_1(x,z)$ satisfying
\begin{equation}
 \supp D_1\subset\Of\times\Cf.
 \label{eq:Dsupport}
\end{equation}
Its local completion terms are supported on $x=z$.
Its coordinate term has $x\in\Kf$ and $z\in\Cf$.
\end{lemma}

\begin{proof}
The coordinate term has the factor $f(x)$ and a retarded
coordinate kernel with $z\in J^-(x)$ and $t_z\geq0$.
The local terms have factors $g(x)$, derivatives of the smooth
$\EAm f(x)$, and derivatives of $\delta(x-z)$.
Since $\supp\EAm f\subset J^-(\Kf)$, their first slot lies
in $\supp g\cap J^-(\Kf)$ and their second slot equals it.
All these sets are compact.
\end{proof}

Consequently, the first scalar slot of a completed tree is
bounded by $\Of$, not necessarily by $\Kf$. Replacing the
too-small bound by \eqref{eq:Dsupport} preserves the relevant
compactness arguments. It does not change the affine-slot
or direct plateau identities.

In this paper X-F's direct polynomial background identity
is used as a prior premise, with this support correction.
The unavailable earlier manuscripts are not presented as
independently verified proofs.

%=====================================================================
\section{The normalized free BRST multiplet}
\label{sec:free}
%=====================================================================

\subsection{Independent fields and the fermion}

Introduce independent fields
\[
 (h,\phi,c^\mu,\bar c_\mu,b_\mu)
\]
with parities $(0,0,1,1,0)$ and ghost numbers
$(0,0,1,-1,0)$.

Define an odd derivation commuting with spacetime derivatives:
\begin{equation}
 \sfree h=Kc,\qquad
 \sfree\phi=0,\qquad
 \sfree c=0,\qquad
 \sfree\bar c=b,\qquad
 \sfree b=0.
 \label{eq:s0}
\end{equation}

\begin{lemma}[Off-shell free nilpotence]
\label{lem:s0nil}
The differential \eqref{eq:s0} is nilpotent on the independent
fields and their graded polynomial differential algebra.
\end{lemma}

\begin{proof}
Its square vanishes on each generator. The square of an odd
derivation is an even derivation, so it vanishes on the
algebra generated by them.
\end{proof}

Choose
\begin{equation}
 \Psi_0=\int\bar c_\mu(C^\mu[h]-b^\mu)\dd^4x.
 \label{eq:Psi0}
\end{equation}
The graded Leibniz rule and $CK=\Box$ give
\begin{equation}
 \sfree\Psi_0
 =\int\bigl(b_\mu C^\mu[h]-b_\mu b^\mu
                         -\bar c_\mu\Box c^\mu\bigr)\dd^4x.
 \label{eq:sPsi}
\end{equation}

\begin{proposition}[Gauge-fixing normalization]
\label{prop:gfnorm}
The auxiliary equation is $b=C[h]/2$. Eliminating it gives
\[
 bC-b^2=\tfrac14C^2-(b-C/2)^2,
\]
and therefore reproduces the frozen gauge-fixing action
$\frac14\int C_\mu C^\mu$.
In the notation $\Psi=\int\bar c(C+\alpha b)$, the required
value is $\alpha=-1$.
\end{proposition}

\begin{proof}
Variation in $b$ gives $C-2b=0$. Completing the square
proves the result.
\end{proof}

The signs are fixed by the chosen action and by
$\sfree\bar c=b$, not by an assumed positive auxiliary measure.
After eliminating $b$,
$\sfree^2\bar c=\frac12\Box c$ is only an on-shell identity.
For off-shell nilpotence, the independent auxiliary field
is retained.

\subsection{The metric--auxiliary Green matrix}

The bosonic Hessian is
\begin{equation}
 L_{hb}=
 \begin{pmatrix}
 A&C^*\\
 C&-2\id
 \end{pmatrix}.
 \label{eq:Lhb}
\end{equation}
For sources $(J,j)$ its equations are
\[
 Ah+C^*b=J,\qquad Ch-2b=j.
\]

\begin{proposition}[Auxiliary Green operators]
\label{prop:Ghb}
The retarded and advanced inverses are
\begin{equation}
 G_{hb}^{\pm}=
 \begin{pmatrix}
 \Delta_\pm^{\mathrm{gr}}&
       \frac12\Delta_\pm^{\mathrm{gr}}C^*\\
 \frac12C\Delta_\pm^{\mathrm{gr}}&
       \frac14C\Delta_\pm^{\mathrm{gr}}C^*-\frac12\id
 \end{pmatrix}
 =
 \begin{pmatrix}
 -4\PP\mathsf E_0^\pm&K\mathsf E_0^\pm\\
 -2C\PP\mathsf E_0^\pm&0
 \end{pmatrix}.
 \label{eq:Ghb}
\end{equation}
\end{proposition}

\begin{proof}
The auxiliary equation gives $b=(Ch-j)/2$, hence
\[
 \Pgr h=J+\tfrac12C^*j.
\]
Apply its Green operator and substitute back.
The identities
\[
 \Delta_\pm^{\mathrm{gr}}C^*=2K\mathsf E_0^\pm,\qquad
 C\Delta_\pm^{\mathrm{gr}}C^*=2\id
\]
follow from \eqref{eq:Cstar}, $\PP^2=\id$, and
$CK=\Box$. They give the second matrix.
Source elimination proves both inverse identities on compact tests.
All blocks have the stated causal support.
\end{proof}

The algebraic $b$ equation does not require imposing zero
Cauchy data on every free field. Retarded inverses select
responses, not a single free configuration.

\subsection{The ghost Green operators}

Use left Grassmann variations. In the order $(c,\bar c)$,
the ghost kinetic matrix and its inverses are
\begin{equation}
 L_{\mathrm{gh}}=
 \begin{pmatrix}0&\Box\\-\Box&0\end{pmatrix},
 \qquad
 G_{\mathrm{gh}}^\pm=
 \begin{pmatrix}0&-\mathsf E_0^\pm\\
                    \mathsf E_0^\pm&0\end{pmatrix}.
 \label{eq:ghostGreen}
\end{equation}
The flat vector--covector fibre pairing is implicit.
Matrix multiplication verifies both inverse identities.

Let
\[
 \delta_\mu=\mathsf E_\mu^{\mathrm R}
                         -\mathsf E_\mu^{\mathrm A}.
\]
The nonzero causal blocks are
\begin{align}
 \Delta_{hh}&=-4\PP\delta_0,
 &\Delta_{\phi\phi}&=-\delta_m,
 \nonumber\\
 \Delta_{hb}&=K\delta_0,
 &\Delta_{bh}&=-2C\PP\delta_0,
 \label{eq:causal}\\
 \Delta_{c\bar c}&=-\delta_0,
 &\Delta_{\bar c c}&=\delta_0.
 \nonumber
\end{align}
The ghost block has the required graded symmetry because
$\delta_0^{\mathsf T}=-\delta_0$.

\subsection{The causal algebra and its differential}

Define $\Afree$ by compactly smeared linear fields, the equations
\begin{equation}
 Ah+C^*b=0,\qquad Ch-2b=0,\qquad
 \Pm\phi=0,\qquad \Box c=\Box\bar c=0,
 \label{eq:freeeq}
\end{equation}
and
\[
 [\Phi_A(f),\Phi_B(k)]_{\mathrm{gr}}
       =i\hbar\pair{f}{\Delta_{AB}k}\mathbf1.
\]
The graded causal form descends to the equation quotient.
Its central graded Lie algebra has an enveloping algebra,
providing the corresponding associative polynomial carrier.

\begin{theorem}[Free causal BRST differential]
\label{thm:freeBRST}
The differential \eqref{eq:s0} preserves the free equations
and causal relations. It induces a nilpotent graded derivation
of $\Afree$.
\end{theorem}

\begin{proof}
The variation of the first metric equation is $AKc=0$.
The variation of $Ch-2b$ is $\Box c$.
The antighost equation varies into $\Box b$.

The latter is a consequence of the bosonic equations:
the linearized Bianchi identity and
\[
 \partial_\mu(C^*b)^{\mu\nu}=-\tfrac12\Box b^\nu
\]
give $\Box b=0$.
The remaining equations are stable.

For the causal relations, the nontrivial cancellation is
the initially zero $h$--$\bar c$ relation:
\[
 \sfree[h,\bar c]_{\mathrm{gr}}
 =\{Kc,\bar c\}+[h,b]
 =-i\hbar K\delta_0+i\hbar K\delta_0=0.
\]
The reversed relation follows by graded symmetry.
All other variations use zero cross-blocks or the zero
$cc$ and $bb$ blocks.
Nilpotence descends from Lemma~\ref{lem:s0nil}.
\end{proof}

\subsection{Compatible Hadamard product data}

For a concrete normal-ordering presentation, choose flat
scalar product kernels $H_\mu$ of a common Hadamard orientation,
normalized by
\[
 H_\mu-H_\mu^{\mathsf T}=i\delta_\mu.
\]
No positivity is required. A compatible translation-invariant
multiplet is
\begin{align}
 H_{hh}&=-4\PP H_0,
 &H_{\phi\phi}&=-H_m,
 \nonumber\\
 H_{hb}&=\tfrac12C_yH_{hh}=K_xH_0,
 &H_{bh}&=\tfrac12C_xH_{hh},
 \label{eq:Hadamard}\\
 H_{bb}&=0,
 &H_{c\bar c}&=-H_0,\qquad H_{\bar c c}=H_0.
 \nonumber
\end{align}
All unspecified blocks vanish.

The blocks are bisolutions, their graded antisymmetric parts
are $i\Delta$, and
\[
 K_xH_{c\bar c}+H_{hb}=0.
\]
The reversed identity follows by slot interchange.
Thus the free differential is also a derivation of the
compatible polynomial Hadamard product.

For compact microcausal polynomial kernels this product is
the finite graded contraction expansion; the wavefront
criterion is unchanged by the finite field matrix and
Koszul signs \cite{FR}.

The notation in \eqref{eq:Hadamard} distinguishes the
scalar equation kernel from the scalar action-Hessian kernel.
A prefactor alone does not reverse a wavefront orientation.
Consequently no sign change from $-4$ to $+4$ is justified
merely by comparing two differently normalized scalar symbols.

If inherited Hadamard data are not translation invariant,
the auxiliary blocks must be defined by their actual slot
derivatives and the compatible presentation transported by
the smooth ordering isomorphism. An unchanged component
formula is not silently asserted in a different ordering
coordinate.

%=====================================================================
\section{The nonlinear kinematics and background ghost operator}
\label{sec:nonlinear}
%=====================================================================

Write
\[
 q=\qb+\kappa h.
\]
The complete formal background may include $\kappa^2\kcl$;
it is held fixed under the quantum-gauge differential.

Define
\begin{equation}
 \begin{aligned}
 sh&=\Lie_c\qb+\kappa\Lie_c h,
 &s\phi&=\kappa c^\mu\partial_\mu\phi,\\
 sc^\mu&=\kappa c^\nu\partial_\nu c^\mu,
 &s\bar c&=b,\qquad sb=0.
 \end{aligned}
 \label{eq:nonlinear}
\end{equation}
Odd coefficients are placed on the left in the component
Lie-derivative formulas.

\begin{lemma}[Kinematical nilpotence]
\label{lem:nonlinear}
The rule \eqref{eq:nonlinear} is nilpotent on the off-shell
graded field algebra.
\end{lemma}

\begin{proof}
Let $w^\mu=c^\nu\partial_\nu c^\mu$.
The graded Lie-derivative identity is
$\Lie_c^2=\Lie_w$.
It follows directly for scalars and covectors by expansion;
the symmetric second-derivative term vanishes by
anticommutativity of the ghosts. The identity extends to
tensor products by the graded Leibniz rule.

Since $sq=\kappa\Lie_cq$,
\[
 s^2q=\kappa\Lie_{sc}q-\kappa\Lie_c(sq)
      =\kappa^2(\Lie_w-\Lie_c^2)q=0.
\]
The scalar calculation is identical.
Direct expansion of $s(c^\nu\partial_\nu c^\mu)$ gives zero
after substitution of $sc$ and antisymmetrization.
The nonminimal pair is nilpotent by definition.
\end{proof}

This is a kinematical differential, not yet an interacting
quantum BRST operator.

\subsection{The natural background fermion}

For the background de Donder vector of X-F, set
\begin{equation}
 \Psi_{\qb}
 =\int\sqrt{-\qb}\,
       \bar c_\mu\bigl(C^\mu_{\qb}[h]-b^\mu_{\qb}\bigr)\dd^4x.
 \label{eq:PsiB}
\end{equation}
The background is $s$-inert, so
\begin{equation}
 s\Psi_{\qb}
 =\int\sqrt{-\qb}\left[
 b_\mu C^\mu_{\qb}[h]-b_\mu b^\mu_{\qb}
 -\bar c_\mu C^\mu_{\qb}[\Lie_c(\qb+\kappa h)]
 \right]\dd^4x.
 \label{eq:sPsiB}
\end{equation}
Eliminating $b$ gives exactly the bosonic gauge fixing of X-F.

Define the background ghost kinetic operator, with its Euler type,
by
\begin{equation}
 (P_{\mathrm{gh}}[\qb]c)^\mu
 =-\sqrt{-\qb}\,C^\mu_{\qb}[\Lie_c\qb].
 \label{eq:Pgh}
\end{equation}

\begin{proposition}[Ghost operator and naturality]
\label{prop:ghost}
With X-E's curvature conventions,
\begin{equation}
 C^\mu_{\qb}[\Lie_c\qb]
 =\bar\Box c^\mu+\bar R^\mu{}_\nu c^\nu.
 \label{eq:ghostclosed}
\end{equation}
Moreover,
\[
 P_{\mathrm{gh}}[F^*\qb](F^*c)
       =F^*(P_{\mathrm{gh}}[\qb]c).
\]
If
\[
 P_{\mathrm{gh}}[\eta+\kappa w]
 =P_{\mathrm{gh}}^{(0)}
       +\kappa P_{\mathrm{gh}}^{(1)}[w]+O(\kappa^2),
 \qquad P_{\mathrm{gh}}^{(0)}=-\Box,
\]
then
\begin{equation}
 P_{\mathrm{gh}}^{(1)}[K\xi]
 =\Lie_\xi P_{\mathrm{gh}}^{(0)}
                 -P_{\mathrm{gh}}^{(0)}\Lie_\xi.
 \label{eq:ghostcomm}
\end{equation}
The left Lie derivative acts on vector densities and the
right one on vectors.
\end{proposition}

\begin{proof}
Trace reversal of $\Lie_c\qb$ gives
\[
 \bar\nabla^\nu c^\mu+\bar\nabla^\mu c^\nu
                      -\qb^{\nu\mu}\bar\nabla_\rho c^\rho.
\]
Take its divergence and commute the two derivatives on
the vector. The commutator contraction is
$\bar R^\mu{}_\nu c^\nu$, giving \eqref{eq:ghostclosed}.

The metric connection, Lie derivative, contractions, and
volume density are natural. This proves the finite identity.
Differentiate it along a compact flow through $\eta$ to
obtain \eqref{eq:ghostcomm}; locality removes the compactness
restriction from the resulting differential identity.
\end{proof}

For $\xi\in\ga$, the retarded inverse
$G_{\mathrm{gh}}^{\mathrm R}=-\ER$ gives the analogous
first-order response identity
\begin{equation}
 -G_{\mathrm{gh}}^{\mathrm R}
       P_{\mathrm{gh}}^{(1)}[K\xi]c
 =\Lie_\xi c
       -G_{\mathrm{gh}}^{\mathrm R}
                    \Lie_\xi P_{\mathrm{gh}}^{(0)}c.
 \label{eq:ghostjet}
\end{equation}
Indeed, $\Lie_\xi c$ is compactly supported and
$G_{\mathrm{gh}}^{\mathrm R}P_{\mathrm{gh}}^{(0)}
\Lie_\xi c=\Lie_\xi c$.
Equation \eqref{eq:ghostjet} is a retarded equation identity.
It does not establish a nonlinear interacting quantum
differential.

%=====================================================================
\section{The switched scalar action: an evaluated breaking}
\label{sec:matter}
%=====================================================================

Consider the natural reference action
\[
 S_{\mathrm{ref}}
 =S_{\mathrm{EH}}+S_g^{\mathrm{sc}}+s\Psi_{\qb},
\]
where
\[
 S_g^{\mathrm{sc}}
 =\int\bigl((1-g)\Lag_\eta[\phi]+g\Lag_q[q,\phi]\bigr)\dd^4x,
\]
\[
 \Lag_q=\tfrac12\sqrt{-q}
       \bigl(q^{\mu\nu}\partial_\mu\phi\partial_\nu\phi
                                      -m^2\phi^2\bigr).
\]
This action is used to evaluate its natural gauge variation.
Its Euler equation is not identified with X-F's
post-variation source-switching prescription.

Put
\[
 T_0^{\mu\nu}
 =\partial^\mu\phi\partial^\nu\phi-\eta^{\mu\nu}\Lag_\eta,
 \qquad
 \partial_\mu T_0^\mu{}_\nu
          =(\Pm\phi)\partial_\nu\phi.
\]

\begin{proposition}[Full switched-matter breaking]
\label{prop:breaking}
For compact ghost coefficient functions, modulo integrated
total derivatives,
\begin{align}
 sS_{\mathrm{ref}}
 =sS_g^{\mathrm{sc}}
 =\kappa\int\bigl[
 &(1-g)T_0^{\mu\nu}\partial_\mu c_\nu
 \nonumber\\
 &+(\partial_\mu g)c^\mu(\Lag_\eta-\Lag_q)
 \bigr]\dd^4x.
 \label{eq:sSfirst}
\end{align}
Equivalently,
\begin{equation}
 sS_g^{\mathrm{sc}}
 =\kappa\int c^\nu\mathfrak B_\nu\dd^4x,
 \label{eq:sS}
\end{equation}
where
\begin{equation}
 \mathfrak B_\nu
 =(\partial_\mu g)T_0^\mu{}_\nu
 -(1-g)(\Pm\phi)\partial_\nu\phi
 +(\partial_\nu g)(\Lag_\eta-\Lag_q).
 \label{eq:B}
\end{equation}
\end{proposition}

\begin{proof}
Naturality gives
$s\Lag_q=\kappa\partial_\mu(c^\mu\Lag_q)$.
The flat metric is held fixed, so its scalar density instead
has variation
\[
 s\Lag_\eta
 =\kappa\left[
 T_0^{\mu\nu}\partial_\mu c_\nu
                  +\partial_\mu(c^\mu\Lag_\eta)\right].
\]
Weight these identities by $g$ and $1-g$ and integrate
the divergence terms. This proves \eqref{eq:sSfirst}.
One more integration by parts and the displayed stress
divergence give \eqref{eq:B}.

The Einstein--Hilbert variation is a compact divergence.
The variation of $s\Psi_{\qb}$ is zero by
Lemma~\ref{lem:nonlinear}.
\end{proof}

The full off-shell breaking is not supported only in
$\supp\dd g$: its equation term with $1-g$ is also present.

\begin{theorem}[A nonzero leading coefficient]
\label{thm:matter}
Every nonzero compact scalar switch with a plateau admits
a free scalar and a compact odd ghost test for which the
coefficient of $\kappa$ in \eqref{eq:sS} is nonzero.
\end{theorem}

\begin{proof}
Use the spatially homogeneous free solution
\[
 \phi_m(t)=
 \begin{cases}
 \sin(mt)/m,&m>0,\\
 t,&m=0.
 \end{cases}
\]
It has $T_0^{00}=1/2$ and $T_0^{0i}=0$.
At the leading metric $q=\eta$, the density difference is zero.

Along a vertical line through a plateau point, $g$ rises
from zero to one. Therefore $\partial_tg>0$ on some open
interior region. Choose a nonnegative nonzero
$\zeta\in C_c^\infty$ there and an odd Grassmann generator
$\vartheta$. Set $c=\vartheta\zeta\partial_t$.
Then
\[
 [sS_g^{\mathrm{sc}}]_{\kappa}
   =\frac{\vartheta}{2}\int\zeta\,\partial_tg\dd^4x\neq0.
\]
\end{proof}

\begin{corollary}[Necessary master-action condition]
\label{cor:CME}
An ordinary canonical BV extension generating
\eqref{eq:nonlinear} and having $S_{\mathrm{ref}}$ as its
antifield-independent action cannot satisfy the classical
master equation with the scalar switch and transformations
unchanged.
A correction starting strictly at $\hbar$ cannot cancel
this classical breaking.
\end{corollary}

\begin{proof}
The antifield-independent coefficient of the classical
master equation requires $sS_{\mathrm{ref}}=0$.
Theorem~\ref{thm:matter} violates this necessary condition.
Coefficient extraction at $\hbar^0$ proves the final assertion.
\end{proof}

This is not a theorem that every observable quantum Ward
coefficient is nonzero. Nor does it exclude a modified
spurion rule, extra compensators, or a different local-coupling
construction. Those would change the sheet.

\subsection{Plateau invariance and the causal qualification}

For a ghost test supported inside $P_g$, the two terms
in \eqref{eq:sSfirst} vanish. The restricted symmetry
therefore survives.

Under a simultaneous background pullback supported in $U$,
the metric, fluctuation, scalar, ghost, antighost, and
auxiliary fields transform in their tensor types.
The fermion and ghost density are natural, $g\circ F^{-1}=g$,
and the flat scalar term is unchanged where its coefficient
$1-g$ is nonzero. Thus the integrated reference action
is exactly invariant under this simultaneous pullback.

This background covariance is different from quantum-gauge
invariance with $\qb$ held fixed.

If an observation point belongs to $P_g$, its vertical past
curve crosses a region where $g$ changes from zero.
Hence $\supp\dd g$ meets its causal past.
Without an observation-plateau or comparable causal
hypothesis, compactness alone does not prove the asserted
intersection.

Even a nonempty causal intersection does not prove a
nonzero ghost contraction with a particular observable.
Propagator support, index contractions, and smearings
still have to be evaluated.

%=====================================================================
\section{Source switching and an exact-upgrade obstruction}
\label{sec:obstruction}
%=====================================================================

\subsection{The necessary reciprocity identity}

For a fixed background $w$ define
\[
 \Nop_w=\sig Q_w.
\]
Since $Q_w$ is formally self-adjoint,
\begin{equation}
 \Nop_w^*=Q_w\sig,\qquad
 \Nop_w-\Nop_w^*=[\sig,Q_w].
 \label{eq:skew}
\end{equation}
Thus source multiplication generally destroys the
symmetry of the action Hessian.

The following on-shell test excludes an equation-zero
representative repair.

\begin{lemma}[Variational reciprocity on free inputs]
\label{lem:reciprocity}
Let an even variational interaction have reduced mixed
metric Hessian $L_w$, with compact coefficients.
If its classical response agrees with
$-\DR\Nop_wu$ on all free metric solutions, then
\begin{equation}
 \Drec_w(u,v)
 :=\int\bigl(u\cdot\Nop_wv-v\cdot\Nop_wu\bigr)\dd^4x=0
 \label{eq:D}
\end{equation}
for all such solution pairs.
\end{lemma}

\begin{proof}
Symmetry of second directional derivatives gives
\[
 \int u\cdot L_wv=\int v\cdot L_wu.
\]
Equality of the retarded responses, followed by application
of $\Pgr$, gives $L_wu=\Nop_wu$ on every free input.
Substitute into the symmetric pairing.
Compactness of the coefficients removes all boundary terms.
\end{proof}

\subsection{A pure-gauge background in the ramp}

A smooth ramp changing from zero to one has
$\sig''\not\equiv0$ on $(0,\eps)$.
Indeed, otherwise it would be affine there, and endpoint
smoothness would force zero slope and hence a constant.

Choose a nonnegative
$\zeta\in C_c^\infty((0,\eps))$ supported where
$\sig''\neq0$, with $\zeta\not\equiv0$, and put
\[
 \psi(t)=\zeta(t)\sig''(t).
\]
Choose
\[
 \chi_0\in C_c^\infty(\R^3),\qquad
 \chi_0\geq0,\qquad
 M_\chi:=\int\chi_0\dd^3x>0.
\]
Set
\begin{equation}
 \xi=\psi(t)\chi_0(\mathbf x)\partial_t,\qquad
 w=K\xi.
 \label{eq:rampgauge}
\end{equation}
This is a permitted classical background.
The vector field $\xi$ here is not asserted to belong
to the plateau algebra: it parametrizes the chosen background,
not an admitted plateau transformation.

Let $e_{00}$ be the tensor whose only nonzero covariant
component is $(e_{00})_{00}=1$, and take
\[
 u=e_{00},\qquad v=te_{00}.
\]
Both satisfy $\Pgr u=\Pgr v=0$.

\begin{proposition}[Evaluated free-solution defect]
\label{prop:Dsigned}
For the background \eqref{eq:rampgauge},
\begin{equation}
 \boxed{
 \Drec_w(u,v)
 =\frac{5M_\chi}{8}\int_0^\eps\sig''\psi\dd t
 =\frac{5M_\chi}{8}\int_0^\eps
                  \zeta(\sig'')^2\dd t>0.}
 \label{eq:Dnonzero}
\end{equation}
\end{proposition}

\begin{proof}
By \eqref{eq:commutator}, on a free input,
$Q_wu=-\Pgr\Lie_\xi u$.

Directly,
\[
 (\Lie_\xi u)_{00}=2\psi'\chi_0,\qquad
 (\Lie_\xi u)_{0i}=\psi\,\partial_i\chi_0,\qquad
 (\Lie_\xi u)_{ij}=0,
\]
and
\[
 (\Lie_\xi v)_{00}=(\psi+2t\psi')\chi_0,\qquad
 (\Lie_\xi v)_{0i}=t\psi\,\partial_i\chi_0,\qquad
 (\Lie_\xi v)_{ij}=0.
\]
For a tensor with no spatial--spatial components,
\[
 (\Pgr a)^{00}=-\tfrac18\Box a_{00}.
\]
It follows that
\[
 (Q_wu)^{00}=\tfrac18\Box(2\psi'\chi_0),\qquad
 (Q_wv)^{00}
       =\tfrac18\Box((\psi+2t\psi')\chi_0).
\]
After spatial integration, the Laplacian terms vanish.
Since
\[
 (\psi+2t\psi')''-t(2\psi')''=5\psi'',
\]
we obtain
\[
 \Drec_w(u,v)
       =\frac{5M_\chi}{8}\int\sig\psi''\dd t.
\]
Twice integrating by parts gives \eqref{eq:Dnonzero}.
\end{proof}

The homogeneous solutions can be replaced by free solutions
with compact Cauchy data. Choose their initial data equal
to those of $u,v$ on a ball containing the initial causal
shadow of $\supp w$, and multiply by a larger compact cutoff.
Finite propagation preserves equality on a neighbourhood
of $\supp w$. Since $Q_w$ is local and supported there,
the value \eqref{eq:Dnonzero} is unchanged.

Together with $b=C[u]/2$ or $C[v]/2$ and zero scalar and
ghost fields, these are configurations of the full free
multiplet.

\begin{theorem}[No exact source-preserving variational upgrade]
\label{thm:obstruction}
There is no upgrade satisfying Definition~\ref{def:upgrade}
on X-F's unrestricted background class.

The contradiction remains if off-shell representatives are
changed by terms vanishing on all free configurations.
It cannot be removed by the algebraic auxiliary field,
ghost loops, or counterterms beginning strictly at quantum order.
\end{theorem}

\begin{proof}
Linearize the claimed reduced action response at zero
fluctuation, zero scalar, and zero ghosts, in the background
\eqref{eq:rampgauge}. Its mixed metric Hessian must satisfy
Lemma~\ref{lem:reciprocity}.
Proposition~\ref{prop:Dsigned} contradicts that condition.

Terms vanishing on all free configurations do not change
the witness. Algebraic auxiliary elimination yields another
action, whose second variation is still symmetric.
Ghost loops and positive-$\hbar$ counterterms do not change
the classical coefficient used in the contradiction.
\end{proof}

\subsection{Relation to density switching}

The quadratic functional
\[
 V_{\mathrm{sym}}[u]
       =\tfrac12\pair{u}{\sig Q_wu}
\]
has Hessian
\begin{equation}
 V_{\mathrm{sym}}''
       =\tfrac12(\sig Q_w+Q_w\sig),
 \label{eq:symmetrized}
\end{equation}
not $\sig Q_w$. Actual switching of a selected density before
variation similarly supplies ramp-derivative terms, with
details depending on the density representative.

These are classical corrections. They cannot be hidden
inside a finite renormalization that starts at $\hbar$.

For $w=K\xi$ with $\xi\in\ga$, the relevant support lies where
$\sig=1$. The witness of this section does not occur in
X-F's particular plateau variation. Therefore the direct
three-tree identity of X-F is not refuted.

What fails is the stronger identification of its entire
source-switched field map with the classical part of one
variational Bogoliubov map for all permitted backgrounds.

%=====================================================================
\section{The one-loop coefficient and its graph inventory}
\label{sec:inventory}
%=====================================================================

\subsection{Bare versus completed observables}

For an actual variational theory, write
\[
 V=\kappa V_1+\kappa^2V_2+O(\kappa^3),
\]
and let the \emph{bare} relational insertion be
\[
 O=F_f+\kappa O_1+\kappa^2O_2+O(\kappa^3),
 \qquad F_f=\int f\phi\dd^4x.
\]
At first order,
\[
 O_1=\phi(c_1[\hcl+h]),
 \qquad c_1[u]=\partial_\mu(fX_1^\mu[u]).
\]
The scalar completion
$-\phi(\mathsf L_{1,g}[u]\EAm f)$ is generated by the
scalar response. It must not also be inserted as an
independent bare term and then regenerated by the same
scalar retarded map.

With
\[
 R_V(O)=\sum_{n\geq0}\frac1{n!}
                     \Rprod_n(V^{\otimes n};O),
\]
the coefficient at order $\kappa^2$ is
\begin{equation}
 O_2+\Rprod_1(V_1;O_1)+\Rprod_1(V_2;F_f)
             +\tfrac12\Rprod_2(V_1,V_1;F_f).
 \label{eq:fullcoefficient}
\end{equation}
This identity is combinatorial. It does not identify a
density-switched tree coefficient with X-F's source-switched one.

\subsection{The precise graph convention}

\begin{assumption}[Graph convention for the inventory]
\label{ass:graphs}
For the inventory below:
\begin{enumerate}[label=\textup{(\alph*)}]
\item free cross-blocks join only matching field species,
apart from the ghost--antighost block;
\item the auxiliary field has been eliminated algebraically;
\item interaction vertices and insertion monomials use a
fixed normal-ordering convention with no self-contractions
at a single vertex;
\item connected contraction graphs are expanded coefficientwise
in the flat free carrier; backgrounds occur through the
explicit vertex coefficients;
\item no additional explicit quantum counterterm is included
in the inventory.
\end{enumerate}
\end{assumption}

At order $\kappa$, the relevant leg types are
\[
 \begin{array}{c|c}
 \text{vertex}&\text{quantum legs}\\ \hline
 V_{1,g}[h,\phi]&h\phi\phi\\
 V_{1,g}[\hcl,\phi]&\phi\phi\\
 \text{mixed metric quadratic vertex}&hh\\
 S_3[h]&hhh\\
 \text{background ghost quadratic vertex}&\bar c c\\
 \text{ghost--metric vertex}&h\bar c c
 \end{array}
\]
Only $h\phi\phi$ carries both a metric and a scalar leg
without a background coefficient.

\begin{proposition}[Two non-tadpole graph types]
\label{prop:inventory}
Under Assumption~\ref{ass:graphs}, the connected
$\kappa^2\hbar$ coefficient of \eqref{eq:fullcoefficient}
has exactly two contraction types:
\begin{enumerate}[label=\textup{(\alph*)}]
\item $\Lalpha$: two lines between the $h\phi$ part of $O_1$
and one $h\phi\phi$ vertex;
\item $\Lbeta$: the $F_f$ scalar line attaches to one
$h\phi\phi$ vertex, and two lines, one metric and one scalar,
join that vertex to a second $h\phi\phi$ vertex.
\end{enumerate}
Each type has one external scalar leg.
Its unextended flat contraction coefficient contains no
$\hcl,\kcl$, ghost field, gravitational cubic vertex,
or background gauge-fixing coefficient.

There are no connected contraction terms at
$\kappa^2\hbar^r$ with $r\geq2$ under these assumptions.
\end{proposition}

\begin{proof}
For $n$ interaction vertices and $E$ contraction lines,
the quantum power is $E-n$. Connectedness requires
$E\geq n$.

For $n=0$, the insertion is normal ordered, so no quantum
contraction occurs.

For $n=1$, the order-one insertion has either one scalar
leg or one scalar and one metric leg.
Quantum order one requires $E=2$.
Both lines must end on the two-leg insertion. The only
order-one vertex with the required species is $h\phi\phi$.
It leaves one scalar leg. A single $V_2$ attached to the
one-leg $F_f$ has at most one line and cannot contribute
at quantum order one.

For $n=2$, the insertion is $F_f$ and has degree one.
Quantum order one requires $E=3$.
One line attaches $F_f$ to a scalar-bearing vertex; the
other two lines must run between the two interaction vertices.
The vertex attached to $F_f$ must therefore have two
remaining legs. The background $\phi\phi$ vertex does not.
The $h\phi\phi$ vertex does, leaving $h\phi$; the only second
vertex matching both species is another $h\phi\phi$ vertex.
Again one scalar leg remains.

The same degree bounds give $E\leq2$ for $n=1$ and
$E\leq3$ for $n=2$. Thus $E-n\leq1$.
Orders $n\geq3$ require at least $\kappa^3$.
\end{proof}

\begin{remark}[What the proposition does not prove]
The proposition does not construct either required nonlocal
retarded operation. It also does not classify every allowed
finite renormalization. An explicitly added order-$\kappa^2\hbar$
counterterm is outside Assumption~\ref{ass:graphs} and must
be tested separately.

The absence of higher-loop contraction graphs is therefore
not an unconditional all-$\hbar$ theorem about every
possible normalized observable.
\end{remark}

\subsection{Tadpoles and the background-dependent boundary}

In the declared convention, a one-vertex tadpole is absent.
A background-dependent graviton, ghost, or scalar one-point
graph requires a second vertex. Feeding that order-$\kappa^2$
metric one-point response through the order-$\kappa$ relational
metric insertion first contributes at $\kappa^3$.

For example, the possible pairs are
\[
 (hhh,\;\hcl hh),\qquad
 (h\bar c c,\;\hcl\bar c c),\qquad
 (h\phi\phi,\;\hcl\phi\phi).
\]
The two legs between the vertices form the loop, while the
metric leg reaches the relational insertion.

A different normal-ordering convention can generate
one-vertex tadpole normalization terms.
Such terms must be included explicitly, rather than
declaring the two-graph inventory universal.
In particular, the word ``one-point function'' must not
silently mean an expectation value in an unspecified state.

The main lesson is narrower than the original plan:
ghosts are necessary for the BRST carrier, but the
non-tadpole scalar coefficient at $\kappa^2\hbar$ does
not contain a ghost loop.

%=====================================================================
\section{The local fish and the nonlocal product criterion}
\label{sec:kernels}
%=====================================================================

\subsection{The ordinary two-vertex fish}

Let $D_F^\mu$ denote flat scalar Feynman product data and
\[
 D_F^{\mathrm{gr}}=-4\PP D_F^0.
\]
The metric--scalar fish between two matter vertices has
finite sums of component kernels of the form
\begin{equation}
 t_{\alpha\beta}(r)
 =D_F^0(r)\,
       \partial^\alpha\partial^\beta D_F^m(r),
 \qquad |\alpha|+|\beta|\leq2,
 \qquad r\neq0.
 \label{eq:fish}
\end{equation}
Tensor coefficients and external scalar derivatives are
suppressed.

\begin{proposition}[Finite-scaling-degree fish extensions]
\label{prop:fish}
The kernels \eqref{eq:fish} are well defined away from
$r=0$ and have scaling degree at most six in four dimensions.
They admit extensions with that scaling-degree bound.
Two such extensions differ by
\begin{equation}
 \sum_{|\gamma|\leq2}a_\gamma\partial^\gamma\delta(r),
 \label{eq:fishambiguity}
\end{equation}
with the relevant tensor coefficients and lower-degree
restrictions for the less singular terms.
\end{proposition}

\begin{proof}
Away from coincidence, null-related Feynman singularities
in the two factors have the same first-slot orientation,
so their nonzero wavefront covectors cannot add to zero.
At spacelike separation both factors are smooth.

A scalar Feynman kernel has scaling degree two.
At most two derivatives occur on the contracted scalar
line, so the product has scaling degree at most
$2+2+2=6$.

The finite-scaling-degree extension theorem gives an
extension without increasing that bound \cite{BF}.
A difference is supported at $r=0$.
A point-supported distribution of scaling degree at most
six in four dimensions has the form \eqref{eq:fishambiguity}.
\end{proof}

The derivative order two in \eqref{eq:fishambiguity} is
the \emph{internal extension ambiguity}. The external
scalar factors may already carry derivatives.
It would be incorrect to infer that every resulting
local quadratic density has total derivative order at most two.

\begin{lemma}[Smoothness after compact kernel smearing]
\label{lem:smoothing}
Let $k(y,y')$ be a distribution with
$\WF(k)\subset\Sigma_2$, where
\[
 \Sigma_2=\{(y,\eta;y',\eta'):\eta+\eta'=0,\ 
                                      (\eta,\eta')\neq0\}.
\]
For a compact smooth $a(y)$, the properly supported
pairing $\int k(y,y')a(y)\dd y$ is smooth in $y'$.
\end{lemma}

\begin{proof}
The pushforward wavefront bound can only produce an output
covector $\eta'$ from a kernel covector with $\eta=0$.
The sum-zero condition then forces $\eta'=0$, which is
not a wavefront covector.
\end{proof}

A translation-invariant extension of \eqref{eq:fish}, lifted
as $k(y,y')=t(y-y')$, has wavefront set in $\Sigma_2$.
Applying Lemma~\ref{lem:smoothing} to the compact scalar
switch and the smoothly smeared insertion leg shows that
the isolated local two-vertex contribution has the form
\[
 \Lbeta=\field(\ell_\beta),\qquad
 \ell_\beta\in C_c^\infty(M),
\]
with compact support supplied by the remaining vertex switch.
This is a local graph construction with the stated finite
normalization freedom. It is not a construction of the
nonlocal mixed retarded product.

\subsection{A scalar model of the coordinate contraction}

The coordinate part of the bare insertion contains a
derivative of $\ER(x,z)$.
Consequently a representative time-ordered scalar contraction
has the underlying product
\begin{equation}
 k_T(x,z,y)
 =\ER(x,z)D_F^0(z,y)D_F^m(x,y).
 \label{eq:triangle}
\end{equation}
The actual insertion has derivatives, tensor contractions,
and smooth coefficient functions. Equation \eqref{eq:triangle}
is used only to audit the scalar product criterion, not to
assert the full loop coefficient equals this one term.

Choose the Hadamard orientation so that the first-slot
Feynman covector is future-pointing at the later endpoint
and past-pointing at the earlier endpoint.
Reversing the Fourier convention reverses all these signs
without changing the argument.

Define
\begin{equation}
 \Nnull=
 \left\{
 \begin{array}{l}
 (x,z,y):\
 y=x-\lambda\ell,\ z=x-\mu\ell,\\
 \ell\neq0\ \text{future null},\
 0\leq\lambda\leq\mu
 \end{array}
 \right\}.
 \label{eq:nullset}
\end{equation}
It includes the corresponding partial coincidences and
the total diagonal.

\begin{proposition}[The exceptional scalar wavefront configuration]
\label{prop:nullWF}
For the scalar kernels in \eqref{eq:triangle}, the sufficient
wavefront product criterion holds off $\Nnull$.
At a strictly ordered null-collinear triple
$z\prec y\prec x$ it fails.

This failure does not prove nonexistence of a distributional
extension, nor nonexistence of the fully contracted retarded
coefficient.
\end{proposition}

\begin{proof}
The three pulled-back wavefront covectors have the forms
\[
 (k,-k,0),\qquad
 (0,l,-l),\qquad
 (p,0,-p)
\]
in the slot order $(x,z,y)$.
Their sum vanishes precisely when
\[
 l=k=-p.
\]
No two nonzero factors alone can give a zero sum because
one endpoint would have an unpaired nonzero covector.

For distinct singular endpoints, all three differences
must be null. Pairwise null-separated points in Minkowski
space are collinear along a null line.
Retarded support puts $z$ before $x$.
The Feynman signs permit $l=-p$ only when $y$ lies
between $z$ and $x$.

At such a triple, choose $p$ future null along the common
line, $k=l=-p$, and use the two-sided null wavefront of the
retarded kernel. The sum is zero, so the criterion fails.
The partial-coincidence cases give the boundary parameters
in \eqref{eq:nullset}; $x=z\neq y$ does not allow cancellation
of the two equal-orientation Feynman covectors.

Thus the product theorem certifies the complement, but
not the exceptional configurations. A sufficient theorem's
failed hypothesis is not a nonexistence proof.
\end{proof}

The corresponding Hadamard product
\[
 k_H(x,z,y)=\ER(x,z)H_0(z,y)H_m(x,y)
\]
satisfies the product criterion everywhere:
$l$ and $p$ have the same fixed Hadamard orientation,
so $l=-p$ is impossible.
It also has a sum-zero wavefront bound in three slots.

This distinction explains why admission of a fixed-width
Wick monomial is not admission of its time-ordered product
with a local vertex.

The ordinary small-diagonal extension of the local fish
does not settle \eqref{eq:triangle}: $\Nnull$ has points
away from the total diagonal. Derivative and tensor
cancellations, or cancellations between terms in the
complete retarded product, may change the answer.
They have not been evaluated here.

Accordingly, the full nonlocal $\Lalpha$ is recorded as
unconstructed, not as proved impossible.

%=====================================================================
\section{What background covariance follows conditionally}
\label{sec:conditional}
%=====================================================================

\subsection{The restricted graph statement}

Suppose the remaining operations are constructed in a
fixed flat graph prescription, and their normalized
coefficients preserve the background independence of
Proposition~\ref{prop:inventory}. Suppose also that the
normal-ordering and finite insertion terms are specified.

Then the loop coefficient has the form
\[
 \field(\ell),\qquad
 \ell\in C_c^\infty(M),
\]
where $\ell$ depends on the observation, switches, mass,
ordering data, and normalization constants, but not
on $(\hcl,\kcl)$.

\begin{theorem}[Conditional fixed-background-input identity]
\label{thm:conditional}
Assume that such an admitted coefficient $\ell$ has been
constructed. Define
\begin{equation}
 \Phi^{\mathrm G}(f)
 =\PhiF(f)+\kappa^2\hbar\,\field(\ell)
       \pmod{\kappa^3,\hbar^2}.
 \label{eq:PhiG}
\end{equation}
If the inherited X-F polynomial identity holds in the
corrected carrier, then under \eqref{eq:twojet}, with the
free fields held fixed,
\[
 \Phi^{\mathrm G}(f)[\hcl',\kcl']
       -\Phi^{\mathrm G}(f)[\hcl,\kcl]
 =0\pmod{\Ideal,\kappa^3,\hbar^2}.
\]
\end{theorem}

\begin{proof}
The tree difference belongs to $\Ideal$ by the inherited
identity. The added coefficient has no dependence on
the two classical backgrounds, so its difference is
identically zero.
\end{proof}

The existence and admissibility hypothesis is substantive.
The theorem is not an unconditional completion of X-G.

It also does not identify \eqref{eq:PhiG} with the Bogoliubov
image of one unchanged interaction. Such an identification
would require the additional compatibility contradicted
by Theorem~\ref{thm:obstruction}.

\subsection{The general variational background gate}

For a new density-switched variational sheet, a more
general proof must construct:
\begin{enumerate}[label=\textup{(\alph*)}]
\item retarded products on all actual local vertices and
the nonlocal relational insertion, including every
coefficient in \eqref{eq:fullcoefficient};
\item quantum comparison maps for the changed background
splittings, with the required perturbative agreement;
\item transport of causal and Hadamard data, rather than
an unproved free pullback automorphism;
\item equation-ideal compatibility and the relevant
finite Ward normalization.
\end{enumerate}

If these data produce the finite intertwiner
\[
 R_{V_{B'}}(O_{B'})
       =R_{V_B}(O_B)\pmod{\Ideal},
\]
then extraction of its $\kappa^2\hbar$ coefficient gives
the requested background identity. Coefficient extraction
is immediate; construction of the intertwiner is not.

The distinction is precisely why general local covariance
and the classical structural argument cannot substitute
for the missing quantum operation \cite{HW,TTZ}.

\subsection{Renormalization freedom and anomalies}

Graph counting does not determine every admissible
finite quantum normalization. Additional local terms
can involve external coupling jets, observation-test
jets, scalar fields, and background curvature data.
The candidate defect is not exhausted by one schematic
expression $\int(\partial\xi)\mathcal R[\hcl]$.

A proof of anomaly removability must:
\begin{enumerate}
\item construct the actual defect;
\item derive its consistency condition;
\item classify the admissible finite normalization terms;
\item solve the cancellation equation within that class.
\end{enumerate}
None of these steps follows from a failed scalar product
criterion or from the absence of a particular unrenormalized
background graph.

The explicit reciprocity defect of
Section~\ref{sec:obstruction} is different.
It is a classical obstruction to an exact source-preserving
field-map identification, not an evaluated one-loop anomaly.

%=====================================================================
\section{Corrections to the proposed continuation}
\label{sec:debug}
%=====================================================================

\paragraph{The three readings of the X-E defect.}
X-F's exact identity
\[
 2\Gtwo(K\xi,u)
       =\Lie_\xi\Glin[u]-\Glin[\Lie_\xi u]
\]
must replace the on-shell shortcut everywhere.
A free gauge-fixed metric need not satisfy $\Glin[u]=0$.
The full background gauge correction packages both
terms into \eqref{eq:commutator}.

\paragraph{The strength of ``Moller response''.}
A retarded solution map for a prescribed equation and
a variational Moller map are not synonyms.
Theorem~\ref{thm:obstruction} separates them for the
frozen source law. The direct tree identity can remain
valid without the stronger variational identification.

\paragraph{The graph-order correction.}
In the declared non-tadpole normal convention,
background-dependent metric one-point loops first feed
the relational scalar at $\kappa^3$, not $\kappa^2$.
The order-$\kappa^2\hbar$ scalar sector contains the two
mixed contraction types of
Proposition~\ref{prop:inventory}.
This is a scheme-qualified statement.

\paragraph{The scalar completion must be counted once.}
Applying the full scalar Bogoliubov map to already
completed $d_1,d_2$ regenerates scalar corrections.
A complete calculation must begin from a bare insertion
or explicitly subtract the duplicated scalar response.

\paragraph{The completed support bound.}
The $g\EAm f$ local terms extend the scalar slot beyond
$\supp f$. The corrected compact set is $\Of$ in
\eqref{eq:correctsets}.

\paragraph{The Hadamard sign.}
No $+4$ replacement is made.
The action-Hessian, equation, causal, and product-kernel
conventions are distinguished in
Section~\ref{sec:free}.
A uniform joint Hadamard orientation must be checked,
not inferred from a coefficient's sign.

\paragraph{The wavefront logical direction.}
Failure of a sufficient product criterion neither
constructs a residue nor proves nonexistence.
No reflected light-ray residue is identified here.

\paragraph{The formal constraint-ideal qualification.}
Suppose a constraint commutator gives
$i\hbar a\mathbf1$ with $a\neq0$.
A two-sided ideal containing that constraint then
contains $\hbar\mathbf1$.
Over $\C[[\hbar]]$ this does not by itself imply it
contains $\mathbf1$.
At fixed nonzero $\hbar$, or after adjoining
$\hbar^{-1}$, the conclusion changes.
No extra de Donder constraint quotient is used here.

\paragraph{The matter support correction.}
The unrestricted off-shell breaking includes
$(1-g)(\Pm\phi)\partial\phi$.
Its leading free-shell coefficient is supported
where $g$ changes. This does not justify an unevaluated
observable Ward-defect claim.

\paragraph{The ordering data at quantum order.}
Unlike the classical tree coefficient, the loop
contractions use the frozen Hadamard/Feynman product
data. Such data are not a chosen state.
Their transport and finite-ordering changes must be
tracked, rather than declared irrelevant.

%=====================================================================
\section{Decision and final release}
\label{sec:decision}
%=====================================================================

\begin{center}
\small
\renewcommand{\arraystretch}{1.12}
\begin{tabularx}{\linewidth}{@{}p{.22\linewidth}X@{}}
\toprule
Gate & Result and scope\\
\midrule
Free BRST carrier &
Constructed: independent auxiliary field, normalized fermion,
ghost action, Green matrix, and causal differential.\\
Background ghost geometry &
Constructed: natural operator, curvature formula, and
pure-gauge commutator identity.\\
Unrestricted master action &
The usual unchanged canonical extension is obstructed by
the evaluated classical matter breaking. No full quantum
master operation is constructed.\\
Exact source-preserving upgrade &
Proved obstructed on the unrestricted X-F background class,
with a nonzero pairing on free metric solutions.\\
G1: local fish &
Finite-scaling-degree extensions constructed, with bounded
local ambiguity.\\
G1: nonlocal insertion &
Unresolved: the full mixed retarded product and its
exceptional-set cancellations or extension are not constructed.\\
G2: one-loop background identity &
Conditional on construction of the coefficient or quantum
transport. Not released unconditionally.\\
G3: finite normalization &
The required complete classification and anomaly-cancellation
equation are not constructed.\\
G4: physical representation &
Positivity, physical cohomology representation, and
Kugo--Ojima analysis are not opened.\\
G5: changed coupling prescription &
Whole-Lagrangian switching, spurions, compensators, and
an adiabatic construction are not opened.\\
\bottomrule
\end{tabularx}
\end{center}

\begin{theorem}[Qualified X-G release]
\label{thm:release}
For the frozen coefficients and background class:
\begin{enumerate}[label=\textup{(\roman*)}]
\item The free BRST multiplet and differential of
Section~\ref{sec:free} are constructed and normalized
to X-E/X-F's graviton operator.
\item The unrestricted scalar gauge variation is
\eqref{eq:B}; its leading coefficient has the nonzero
free-shell witness of Theorem~\ref{thm:matter}.
\item No exact source-preserving variational upgrade
satisfying Definition~\ref{def:upgrade} exists.
The explicit obstruction is
\[
 \frac{5M_\chi}{8}
       \int_0^\eps\zeta(\sig'')^2\dd t>0.
\]
\item Under Assumption~\ref{ass:graphs}, the two mixed
contraction types exhaust the non-tadpole
$\kappa^2\hbar$ inventory. The local fish admits the
extensions of Proposition~\ref{prop:fish}.
\item The scalar nonlocal product criterion has the
exceptional configuration of
Proposition~\ref{prop:nullWF}. Its failure is not a
nonexistence theorem.
\item Theorem~\ref{thm:conditional} is a conditional
background-identity result. The existence assumptions
needed for an unconditional one-loop completion have
not been replaced by an asserted covariance principle.
\end{enumerate}
\end{theorem}

\begin{proof}
Item (i) is Proposition~\ref{prop:gfnorm},
Proposition~\ref{prop:Ghb}, and
Theorem~\ref{thm:freeBRST}.
Item (ii) is Proposition~\ref{prop:breaking} and
Theorem~\ref{thm:matter}.
Item (iii) is Theorem~\ref{thm:obstruction}.
Item (iv) is Proposition~\ref{prop:inventory} and
Proposition~\ref{prop:fish}.
Item (v) is Proposition~\ref{prop:nullWF}.
Item (vi) is the coefficientwise proof of
Theorem~\ref{thm:conditional} and its stated hypotheses.
\end{proof}

\subsection*{The three endings}

The free algebraic construction reaches
\textbf{Constructed}.

The exact source-preserving variational interpretation
reaches \textbf{Proved obstructed}, with the quantifiers
of Definition~\ref{def:upgrade}.

The originally requested unconditional one-loop
background completion reaches \textbf{Unresolved}
on the supplied prescription. Calling it constructed
would require either:
\begin{enumerate}
\item a non-variational quantum prescription with all
its operations and identities proved; or
\item a newly declared variational sheet, including its
classical ramp corrections and the full nonlocal quantum
transport construction.
\end{enumerate}
Neither is silently inserted into X-G.

A missing operation is recorded as missing. An explicit
classical incompatibility is recorded as an obstruction.
A failed sufficient microlocal criterion is recorded as
neither.

%=====================================================================
\appendix
\section{Coefficient and logical audit}
\label{app:audit}
%=====================================================================

\subsection{The free coefficients}

The fixed chain is
\[
 \Psi_0=\int\bar c(C-b),\qquad
 b=C/2,\qquad S_{\mathrm{gf}}=\tfrac14\int C^2,
\]
\[
 \Pgr=-\tfrac14\PP\Box,\qquad
 \DR=-4\PP\ER,\qquad
 \Delta_{hb}=K\delta_0,\qquad
 \Delta_{c\bar c}=-\delta_0.
\]
It produces the free cancellation
\[
 \{Kc,\bar c\}+[h,b]=0.
\]
Changing $b=C/2$ to $b=C$ while leaving the other entries
unchanged breaks this chain.

\subsection{Why the obstruction is isolated}

For the witness in Section~\ref{sec:obstruction}, the
scalar and ghost fields are zero. Linearization is at
zero metric fluctuation.
The gravitational self source is quadratic in that
fluctuation and therefore does not contribute to the
linearized mixed response.
Thus neither an omitted matter tree nor an unevaluated
self-tree can cancel the pairing \eqref{eq:Dnonzero}.

\subsection{Why it does not contradict plateau covariance}

The vector field defining the witness is supported in
the ramp, not in $U$. It specifies an allowed background
$w=K\xi$. The no-go tests the response on all backgrounds;
it does not apply a forbidden parameter as a plateau
symmetry.

Conversely, X-F's direct identity uses parameters supported
in $U$, where $\sig=1$. These are distinct tests.

\subsection{Why conditional background independence is easy}

If a completed coefficient is literally
$\field(\ell)$ with $\ell$ independent of the backgrounds,
its held-fixed variation is zero.
This observation does not construct $\ell$, prove that
it is the intended retarded coefficient, or impose
perturbative agreement. These are the three missing
inferences avoided in Section~\ref{sec:conditional}.

\section*{Declarations}
\addcontentsline{toc}{section}{Declarations}

\paragraph{Dependencies.}
The signed quadratic action, scalar switch, completed
test formula, and tensor conventions are taken from
the supplied \texttt{X-E.tex}.
The background gauge operator, exact commutator, source
prescription, and direct tree identity are taken from
the supplied \texttt{X-F.tex}.
Earlier series results are premises where explicitly
identified, not independently verified here.

\paragraph{New proofs.}
The normalized auxiliary--ghost Green matrix and free
causal differential; the background ghost operator;
the evaluated switched-matter coefficient; the
free-solution reciprocity obstruction using a compact
pure-gauge ramp background; the qualified contraction
inventory; the corrected completed support bound; and
the scalar nonlocal product-criterion audit.

\paragraph{Quantum scope.}
No interacting quantum BRST differential, complete
master equation, full nonlocal loop value, anomaly
cancellation, state, positivity theorem, physical
representation, sharp-width limit, or adiabatic limit
is constructed.

\paragraph{VII-C.}
The word $B_f\star W_g\star B_{f'}$ and its extension
hypotheses are not constructed.
No residue identification or subtraction is made.
The present scalar exceptional-set audit does not
apply VII-C's theorem.

\paragraph{Einstein jet.}
The earlier switched-source conservation condition is
not changed. No claim is made that the generically
empty coupled Einstein jet has been filled.

\paragraph{Verification status.}
The source is standalone and requires no external
figures, bibliography database, or executable code.
The source has been organized to avoid unresolved
local labels and external cross-reference commands.
No successful \texttt{pdflatex} execution,
proof-assistant check, numerical verification,
independent referee review, or journal acceptance
is asserted.

%=====================================================================
\begin{thebibliography}{99}
\addcontentsline{toc}{section}{References}

\bibitem{XE}
N.~Cheung.
\newblock \emph{Landmark X-E: A specified gravitational action
for the ramp relational scalar, and the first graviton tree}.
\newblock Supplied manuscript \texttt{X-E.tex}.

\bibitem{XF}
N.~Cheung.
\newblock \emph{Landmark X-F: The second-order quantum metric
as the retarded Moller response, and the closure of the
$\kappa^2$ background identity}.
\newblock Supplied manuscript \texttt{X-F.tex}.

\bibitem{BF}
R.~Brunetti and K.~Fredenhagen.
\newblock Microlocal analysis and interacting quantum field
theories: renormalization on physical backgrounds.
\newblock \emph{Communications in Mathematical Physics}
208 (2000), 623--661.
\newblock arXiv:math-ph/9903028.
\newblock Used for the finite-scaling-degree extension theorem,
not as a construction of the nonlocal mixed retarded product.

\bibitem{FR}
K.~Fredenhagen and K.~Rejzner.
\newblock \emph{Perturbative algebraic quantum field theory}.
\newblock arXiv:1208.1428v2, 2013.
\newblock Background for polynomial Hadamard products,
retarded products, and ordering equivalences.

\bibitem{HW}
S.~Hollands and R.~M.~Wald.
\newblock Conservation of the stress tensor in perturbative
interacting quantum field theory in curved spacetimes.
\newblock \emph{Reviews in Mathematical Physics}
17 (2005), 227--312.
\newblock arXiv:gr-qc/0404074v2.
\newblock Used to distinguish perturbative agreement from
the preceding covariance and normalization conditions.
Its scalar-field theorem is not imported as a graded
gravitational completion.

\bibitem{TTZ}
M.~Taslimi Tehrani and J.~Zahn.
\newblock Background independence in gauge theories.
\newblock \emph{Annales Henri Poincare}
21 (2020), 1135.
\newblock arXiv:1804.07640v3.
\newblock Comparison for quantum background transport and
possible obstructions. No anomaly-removal theorem for the
present switched model is inferred.

\bibitem{BFR}
R.~Brunetti, K.~Fredenhagen, and K.~Rejzner.
\newblock Quantum gravity from the point of view of locally
covariant quantum field theory.
\newblock \emph{Communications in Mathematical Physics}
345 (2016), 741--779.
\newblock arXiv:1306.1058.
\newblock Comparison framework for locally covariant
perturbative gravity and renormalized BV constructions.
It does not identify source switching with density switching.

\bibitem{Hor}
L.~H\"ormander.
\newblock \emph{The Analysis of Linear Partial Differential
Operators I}, second edition.
\newblock Springer, 1990.
\newblock Used for the wavefront product and pushforward
criteria. A failed sufficient product criterion is not
used as a nonexistence theorem.

\end{thebibliography}

\end{document}