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\title{\textbf{Hawk07-B}\\[4pt]
Operational Functions and Conditional Predictions\\
for Finite Wormhole Certificates\\[3pt]
\large Payload scaling, private recovery, hybrid communication,
and resource-priced composition in the Enter framework}
\author{Ngo Cheung}
\date{15 October 2026}

\begin{document}
\maketitle

\begin{abstract}
We extrapolate the finite model of Hawk07-A by proving
dimension-dependent recovery, operational-function, and composition
theorems. The word ``wormhole'' denotes a declared quantum-return
certificate, not a spacetime tunnel.

For a logical payload of dimension \(d\), an independent maximally
entangled early resource, one known Haar-sampled vault unitary, and
nested release, we rederive the complete complementary moment and
obtain a sufficient full-diamond recovery threshold
\[
 r_*\ge \frac{4d^2\sqrt f}{\varepsilon^2\sqrt p}.
\]
Here \(r_*\) is the released quantum dimension, not the entire
receiver dimension; \(f\) is the blank-factor dimension; and
\(p\) is the allowed measure of uncertified devices.
A positive-residual, multi-cut design is given explicitly.
The proposed inverse-linear error scaling is corrected to the
inverse-square scaling actually supplied by this certificate.
No optimality claim is made.

The certified operational functions include referenced state return,
entanglement transfer, classical message transmission, logical
postprocessing, and privacy against the declared complete residual.
For square-power payload dimensions, a new calculation proves
coexistence of recovery and coherent entropy turnover on a family
of Haar measure at least \(1/(4d)\), with one physical residual qubit
at the final cutoff. This extends, rather than silently reuses,
Hawk07-A's dimension-\(16\) calculation.

A finite convoy is constructed using separately prepared resources.
Its joint error is bounded even for mutually entangled payloads.
A different theorem states a sufficient complete memory-reset contract
for reuse; small previous leakage alone does not supply that contract.
Noise, batch workspace, classical communication, terminal discard,
and the distinction between a quantum payload and a classical log
are accounted for separately.

These are conditional predictions of finite quantum-information
models. They predict neither transport of a material spacecraft
through spacetime nor a metric, travel time, energy condition,
fuel cost, gravitational Page curve, or geometric wormhole.
\end{abstract}

\paragraph{Scope of ``prediction.''}
A prediction below is a consequence of explicitly stated preparation,
channel, access, and implementation hypotheses.
It is not an observation, an empirical forecast of gravitational
wormholes, or a claim that those hypotheses have been implemented.

\tableofcontents

%=====================================================================
\section{Enter philosophy, the analogy, and necessary corrections}
\label{sec:background}
%=====================================================================

\subsection{Background}

The Philosophy of Enter separates destructive readout from quantum
return, and channel descriptions from thermodynamic or geometric
identifications. An interface must specify its input, accessible
systems, returned output, retained references, and permitted
continuations \cite{CheungPhilosophy}.

In the Enter calculus, a runtime qubit name grants access to a tensor
factor. Destructive Enter consumes the measured name and returns a
classical record. The Born instrument is a declared semantics;
the operational characterization of that semantics is a separate
result within a specified strategy class \cite{CheungEnter,CheungI}.
This manuscript does not rederive measurement probabilities from
wormhole terminology.

The mathematical setting here is ordinary finite-dimensional quantum
theory. Enter contributes the discipline of stating access and return
types explicitly. Entanglement, scrambling, release, decoding, and
communication are additional resources, not consequences of naming
an operation.

The geometric ER \(=\) EPR proposal and gravitational traversability
constructions concern additional geometric and dynamical data
\cite{MaldacenaSusskind,GaoJafferisWall,MaldacenaStanfordYang}.
They motivate comparisons, but provide no automatic dictionary
for the finite factors used here.

\subsection{The spaceship analogy}

A ``ship'' will mean a finite logical factor \(L\), possibly entangled
with an untouched reference. It does not mean a specified mass
distribution, material body, world tube, or gravitational source.

The receiver \(R\) and complete residual \(B\) are the two
\emph{operational mouths}. The complete complementary channel is
the object called a \emph{throat} in the overlay. It is a channel,
not a third register or a tunnel.

``Travel'' means returning the logical payload through a specified
receiver with a quantified error. The model does not assert motion
of its laboratory qubits through a spacetime bridge.

\subsection{Debugging the extrapolation}

\begingroup
\small
\renewcommand{\arraystretch}{1.13}
\begin{longtable}{@{}p{.35\linewidth}p{.60\linewidth}@{}}
\caption{Corrections required for the extrapolated claims.}
\label{tab:corrections}\\
\toprule
Proposed inference & Corrected statement\\
\midrule
\endfirsthead
\toprule
Proposed inference & Corrected statement\\
\midrule
\endhead
\bottomrule
\endfoot

The accessible dimension is
\(O(d^2\sqrt f/\varepsilon)\).
&
The supplied diamond certificate gives a sufficient
\emph{released} dimension
\(r_*=O(d^2\sqrt f/(\varepsilon^2\sqrt p))\).
The complete receiver has dimension \(r_*h\), with early-memory
dimension \(h\).
\\[5pt]

The \(d^2\) threshold is a universal necessary cost.
&
It is a sufficient bound from the particular
Choi-to-diamond argument. Its dimension factor cannot be omitted
from that argument, but a different encoding can recover exactly
with smaller released dimension.
\\[5pt]

Before the sufficient threshold, recovery must be poor.
&
At cut zero the accessible channel is exactly replacement.
At other cuts, failure of a sufficient estimate is inconclusive;
it is not a lower recovery bound.
\\[5pt]

Hawk07-A's measure \(1/64\) applies unchanged as \(d\) grows.
&
That constant was proved for its dimension-\(16\) construction.
The scaled turnover calculation below has its own dimensions,
hypotheses, and measure.
\\[5pt]

A receiver certified at every later cut returns the same input
repeatedly.
&
These are alternative stopping interfaces before decoding.
One actual quantum return consumes or transforms its receiver input.
The statement is not repeated copying of one payload.
\\[5pt]

Nested access licenses a convoy through one reused vault.
&
A convoy needs new injection and memory contracts.
Independent stock-prepared sessions and a uniformly certified
memory-reset device are different constructions.
\\[5pt]

Previous residual leakage is small, so the next resource is fresh.
&
Logical input independence does not imply the required resource
state, independence from old systems, or workspace restoration.
\\[5pt]

A beacon works, so the whole ship works.
&
An effect can be reconstructed while full-code recovery fails.
Conversely, full-code recovery implies accurate measurement of
every specified effect.
\\[5pt]

Residual Enter yields an album containing the recovered quantum
payload.
&
It yields an appended residual record. Its Shannon entropy is
nondecreasing, but the record need not encode the payload.
Quantum return remains a different interface.
\\[5pt]

The ideal error already uses all of \(\varepsilon\), so small
implementation errors preserve the same allowance.
&
Channel and decoder errors require reserved headroom.
Their half-diamond allowances add to the ideal error.
\\[5pt]

An energy condition must be assumed in every geometric successor.
&
A successor must state and justify its stress and energy-condition
properties. They may be assumptions or derived consequences of
a specified gravitational model.
\\
\end{longtable}
\endgroup

All companion sheets are comparisons with their own models.
The calculations below are stated and proved locally.
In particular, the attached Hawk07-A is a predecessor
\cite{CheungHawk07A}, not permission to change its model without
rechecking the hypotheses.

%=====================================================================
\section{Complete interfaces and their information tasks}
\label{sec:interfaces}
%=====================================================================

All Hilbert spaces in the main model are finite dimensional.
Channels act on matrix algebras in the Schr\"odinger picture.
For states and channels set
\[
 \dtr(\rho,\sigma)=\frac12\norm{\rho-\sigma}_1,\qquad
 \ddiam(\Phi,\Psi)=\frac12\norm{\Phi-\Psi}_\diamond.
\]
The diamond norm includes arbitrary untouched references
\cite{WatrousBook}.

\begin{definition}[Complete interface and diagnostics]
\label{def:interface}
A complete interface is an isometry
\[
 V:L\longrightarrow R\otimes B,\qquad \dim L=d\ge2.
\]
Its accessible and complementary channels are
\[
 \Nchan(X)=\Tr_B(VXV^\dagger),\qquad
 \Cchan(X)=\Tr_R(VXV^\dagger).
\]
Every unreturned purifier, lost mode, apparatus environment, and
record store required by the declared realization belongs to the
complete residual. An untouched external reference is not granted
to the decoder.

For a state \(\tau\), define
\[
 \rep{\tau}(X)=\Tr(X)\tau,
\]
\[
 \erec(\Nchan)=
 \inf_{\Dchan\ {\rm CPTP}}
 \ddiam(\Dchan\Nchan,\id_L),\qquad
 \dleak(\Cchan)=
 \inf_{\tau_B}\ddiam(\Cchan,\rep{\tau_B}).
\]
Write \(a_d=1-d^{-2}\) and \(b_d=1-d^{-1}\).
\end{definition}

\begin{definition}[Operational wormhole certificate]
\label{def:certificate}
A tuple \((V,R,B,\Dchan,\varepsilon)\) is an operational wormhole
certificate when:
\begin{enumerate}[label=\textup{(\roman*)}]
\item \(V\) is a complete isometry and the receiver accesses only \(R\);
\item \(\Dchan:\BB(R)\to\BB(L_{\rm out})\) is a specified deterministic
CPTP quantum-return map;
\item \(\norm{\Dchan\Nchan-\id_L}_\diamond\le\varepsilon\);
\item physical \(B\) remains a declared output factor;
\item no two commuting code-preserving star representations both
implement the same logical algebra through \(V\).
\end{enumerate}
The terms ``mouth'' and ``throat'' add no geometric hypothesis.
\end{definition}

\begin{theorem}[Exact recovery, dimension, and approximate correction]
\label{thm:correction}
For a complete interface:
\begin{enumerate}[label=\textup{(\roman*)}]
\item exact full-code recovery from \(R\) is equivalent to
\(\Cchan=\rep{\tau_B}\);
\item if exact recovery holds and \(s=\rank\tau_B\), then
\(\dim R\ge ds\);
\item
\begin{equation}
 \erec(\Nchan)\le
 \min\{a_d,\sqrt{2\dleak(\Cchan)}\};
 \label{eq:correction}
\end{equation}
\item if \(\ddiam(\Nchan,\rep{\omega_R})\le\eta\), then
\begin{equation}
 \erec(\Nchan)\ge\max\{0,a_d-\eta\}.
 \label{eq:replacementlower}
\end{equation}
\end{enumerate}
\end{theorem}

\begin{proof}
For exact recovery, dilate a decoder by \(W:R\to L_{\rm out}G\).
The composite \((W\otimes I_B)V\) dilates identity. The rank-one
Choi operator of identity implies
\[
 (W\otimes I_B)V\ket{\psi}
 =\ket{\psi}\ket{\chi}_{GB}
\]
for fixed \(\chi\), proving complement constancy.

Conversely, diagonalize
\(\tau_B=\sum_{\alpha=1}^s\lambda_\alpha\kb{\alpha}{\alpha}\)
on its nonzero support. Write
\[
 V\ket{i}=\sum_\alpha\sqrt{\lambda_\alpha}
                  \ket{u_{i\alpha}}_R\ket{\alpha}_B.
\]
Constancy on matrix units gives
\(\langle u_{j\beta}\mid u_{i\alpha}\rangle
=\delta_{ij}\delta_{\alpha\beta}\).
The resulting \(ds\) orthonormal vectors define an isometry
\(T:L\mathbb C^s\to R\) and
\[
 \Nchan(X)=T(X\otimes\sigma)T^\dagger.
\]
The map
\[
 \Dchan(Y)=
 \Tr_{\mathbb C^s}(T^\dagger YT)
 +\Tr((I-TT^\dagger)Y)\omega_L
\]
is CPTP and exactly recovers the code. This is the
Knill--Laflamme structure \cite{KnillLaflamme}.

The information--disturbance estimate gives
\[
 \frac14
 \left(\inf_{\Dchan}
       \norm{\Dchan\Nchan-\id_L}_\diamond\right)^2
 \le \inf_\tau\norm{\Cchan-\rep{\tau}}_\diamond
 \cite{KSW}.
\]
Changing normalization gives the square-root bound.

A decoded replacement has Bell overlap \(d^{-2}\), hence
half-diamond error at least \(a_d\). Preparing \(I_L/d\)
attains this value: depolarization is a uniform average of
\(d^2\) Weyl conjugations, including identity.
It also supplies the universal constant-decoder cap.
Contraction and the triangle inequality prove
\eqref{eq:replacementlower}.
\end{proof}

The criterion is for the entire declared input, not a single effect
or an unspecified subsystem
\cite{CheungOai290280,CheungHawk04B,CheungEn07B}.

\begin{proposition}[No commuting duplicate]
\label{prop:noduplicate}
For \(d\ge2\), two commuting star representations
\(\pi_1,\pi_2\) cannot both satisfy
\[
 \pi_j(X)V=VX\qquad(X\in\BB(L)).
\]
\end{proposition}

\begin{proof}
Commutation would give
\[
 VXY=\pi_1(X)\pi_2(Y)V
 =\pi_2(Y)\pi_1(X)V=VYX.
\]
Injectivity of \(V\) would make \(\BB(L)\) commutative.
\end{proof}

This excludes duplicate actions on the same code, not commuting
algebras of independent degrees of freedom
\cite{CheungHawk03A}.

%=====================================================================
\section{Scaled preparation and a rederived recovery threshold}
\label{sec:scaling}
%=====================================================================

\subsection{One payload, one sampled device}

Declare
\[
 L\simeq\mathbb C^d,\quad
 H\simeq\mathbb C^h,\quad
 E\simeq\mathbb C^h,\quad
 F\simeq\mathbb C^f.
\]
Before the unknown payload is used, prepare the independent resource
\[
 \ket{\Phi_h}_{HE}
 =h^{-1/2}\sum_{a=1}^h\ket{a}_H\ket{a}_E,
 \qquad \ket{0}_F.
\]
The vault \(LHF\) has dimension \(D=dhf\).
Sample one Haar unitary \(U\in U(D)\), retain its device description,
and use that same \(U\) at every cut.

At cut \(k\), regroup the vault as \(P_kB_k\), with
\[
 r_k=\dim P_k,\qquad b_k=\dim B_k,\qquad r_kb_k=D.
\]
The receiver is the entire factor
\[
 R_k=P_kE,\qquad \dim R_k=r_kh.
\]
The reference \(Q\), possibly entangled with \(L\), is untouched.
The complete isometry is
\begin{equation}
 V_k^U\ket{\psi}
 =
 (U\otimes I_E)
 (\ket{\psi}_L\ket{\Phi_h}_{HE}\ket{0}_F),
 \label{eq:model}
\end{equation}
with the indicated output regrouping.
Later release does not act on already released cells.

This is a finite entanglement-assisted recovery task, comparable in
structure to Hayden--Preskill retrieval \cite{HaydenPreskill}.
It is not a model of its gravitational dynamics.

\subsection{The dimension-dependent moment}

For the normalized Bell input on \(QL\), put
\[
 \omega_{QB}^U=(\id_Q\otimes\Cchan^U)
                  (\kb{\Phi_d}{\Phi_d}),\quad
 \sigma_B^U=\Cchan^U(I_L/d),
\]
\[
 X_{QB}^U=\omega_{QB}^U-I_Q/d\otimes\sigma_B^U,\qquad
 z(U)=\ddiam(\Cchan^U,\rep{\sigma_B^U}).
\]

\begin{theorem}[Complementary moment at arbitrary payload dimension]
\label{thm:moment}
At a cut \(D=rb\),
\begin{align}
 \Expect_U\norm{X_{QB}^U}_2^2
 &=
 \frac{r(b^2-1)(d^2-1)}
      {d^2h(D^2-1)}, \label{eq:moment}\\
 \Expect_U z(U)^2
 &\le
 \mathsf K(r,b):=
 \frac{dD(b^2-1)(d^2-1)}
      {4h(D^2-1)}
 \le\frac{d^4f}{4r^2}.
 \label{eq:momentbound}
\end{align}
\end{theorem}

\begin{proof}
The two-copy Haar twirl of
\(I_{PP'}\otimes\Swap_{BB'}\) is \(\alpha I+\beta\Swap\), where
\[
 \alpha=\frac{b(r^2-1)}{D^2-1},\qquad
 \beta=\frac{r(b^2-1)}{D^2-1}.
\]
Indeed, the twirl commutes with all \(U\otimes U\), and its
identity and swap coefficients are fixed by the traces
\(r^2b\) and \(rb^2\).

After tracing \(E\), the initial reference--vault state is
\[
 \kb{\Phi_d}{\Phi_d}_{QL}\otimes I_H/h\otimes\kb{0}{0}_F.
\]
Its purity is \(1/h\), its vault marginal has purity \(1/(dh)\),
and its reference marginal has purity \(1/d\).
The swap identity therefore gives
\[
 \Expect\Tr[(\omega_{QB}^U)^2]=\alpha/d+\beta/h,\qquad
 \Expect\Tr[(\sigma_B^U)^2]=\alpha+\beta/(dh).
\]
Subtracting the second expression divided by \(d\) proves
\eqref{eq:moment}.

For an input dimension \(d\), normalized Choi operators obey
\[
 \norm{\Phi-\Psi}_\diamond
 \le d\,\norm{\Jn(\Phi)-\Jn(\Psi)}_1.
\]
To see the factor, write any pure referenced input as
\((T\otimes I)\ket{\Phi_d}\), with
\(\Tr(T^\dagger T)=d\) and \(\norm{T}_\infty^2\le d\).
Apply trace-norm multiplication bounds and then convexity
\cite{WatrousBook}.
Since \(X_{QB}^U\) acts on dimension \(db\),
\[
 z(U)^2\le\frac{d^2}{4}\norm{X_{QB}^U}_1^2
 \le\frac{d^3b}{4}\norm{X_{QB}^U}_2^2.
\]
Taking expectations gives \(\mathsf K\).
Finally use
\[
 \frac{b^2-1}{D^2-1}\le\frac{b^2}{D^2},\qquad
 d^2-1\le d^2,\qquad D=dhf,\qquad b=D/r.
\]
\end{proof}

This repeats the general calculation on the newly declared dimensions;
it does not infer dimension scaling from Hawk07-A's special
turnover theorem.

\subsection{Nested access and the threshold}

\begin{proposition}[Monotonicity under release]
\label{prop:nested}
For the specified nested schedule,
\[
 \erec(\Nchan_{k+1}^U)\le\erec(\Nchan_k^U),\qquad
 \dleak(\Cchan_{k+1}^U)\le\dleak(\Cchan_k^U),\qquad
 z_{k+1}(U)\le z_k(U).
\]
\end{proposition}

\begin{proof}
Discarding the additional received cells takes \(\Nchan_{k+1}^U\)
to \(\Nchan_k^U\), so an earlier decoder remains an available policy.
The later complement is a partial trace of the earlier complement.
That partial trace maps replacement channels to replacement channels
and maps the named center \(\sigma_{B_k}^U\) to
\(\sigma_{B_{k+1}}^U\). Use diamond contraction.
\end{proof}

\begin{theorem}[Scaled, all-later-cut certificate]
\label{thm:threshold}
Fix \(0<p<1\), \(\zeta>0\), a positive-residual cutoff \(K\),
and a retained cut \(k_*\le K\).
If
\[
 \mathsf K(r_{k_*},b_{k_*})\le p\zeta^2,
\]
then, with Haar probability at least \(1-p\), the same sampled device
has
\[
 z_k(U)\le\zeta,\qquad
 \erec(\Nchan_k^U)\le\min\{a_d,\sqrt{2\zeta}\}
 \quad(k_*\le k\le K).
\]
A sufficient condition is
\[
 r_{k_*}\ge\frac{d^2\sqrt f}{2\zeta\sqrt p}.
\]
For full-diamond target \(0<\varepsilon<1\), the choice
\(\zeta=\varepsilon^2/8\) gives the sufficient condition
\begin{equation}
 \boxed{
 r_{k_*}\ge\frac{4d^2\sqrt f}{\varepsilon^2\sqrt p}.
 }
 \label{eq:fullthreshold}
\end{equation}
\end{theorem}

\begin{proof}
Markov's inequality bounds
\[
 \Prob\{z_{k_*}(U)>\zeta\}
 \le\mathsf K(r_{k_*},b_{k_*})/\zeta^2.
\]
Proposition~\ref{prop:nested} propagates this one event to every
later retained cut. Apply Theorem~\ref{thm:correction}.
The full-diamond error is at most \(2\sqrt{2\zeta}\).
\end{proof}

The probability concerns the selection of a device \(U\).
It is not a decoder success flag or the probability that a
particular input survives one use.

\begin{proposition}[What the initial phase does and does not imply]
\label{prop:initial}
At cut zero, for every \(U\),
\[
 \Nchan_0^U=\rep{I_E/h},\qquad
 \erec(\Nchan_0^U)=\dleak(\Cchan_0^U)=a_d.
\]
No comparable lower bound at an arbitrary nonzero cut follows
merely because \eqref{eq:fullthreshold} has not been met.
\end{proposition}

\begin{proof}
A unitary confined to the vault leaves its inaccessible reference
marginal \(E\) unchanged. The complement is
\[
 X\longmapsto
 U(X\otimes I_H/h\otimes\kb{0}{0}_F)U^\dagger.
\]
Undoing \(U\) and tracing \(HF\) recovers \(X\).
Contraction through this inverse gives a leakage lower bound \(a_d\);
comparison with the output on \(I_L/d\) gives the matching upper bound.
Theorem~\ref{thm:threshold} is sufficient, not necessary, so its
failure supplies no converse.
\end{proof}

%=====================================================================
\section{Payload-resource tradeoffs before a positive cutoff}
\label{sec:resources}
%=====================================================================

\subsection{Fixed residual dimension}

At a cut with specified residual dimension \(b\),
\eqref{eq:momentbound} becomes
\[
 \mathsf K=
 \frac{d^2f(b^2-1)(d^2-1)}
      {4(d^2h^2f^2-1)}.
\]
Thus its exact second-moment sufficient condition is
\begin{equation}
 h^2\ge
 \frac1{d^2f^2}
 +\frac{(b^2-1)(d^2-1)}{4p\zeta^2f}.
 \label{eq:exacth}
\end{equation}
With \(\zeta=\varepsilon^2/8\), this reads
\[
 h^2\ge
 \frac1{d^2f^2}
 +\frac{16(b^2-1)(d^2-1)}{p\varepsilon^4f}.
\]
These are design allowances, not a converse capacity theorem.

\begin{theorem}[Explicit multi-cut design for any qubit payload]
\label{thm:design}
Let \(d=2^\ell\), \(\ell\ge1\), take \(f=1\), choose
\(0<\varepsilon<1\), \(0<p<1\), and integers \(q\ge1\), \(w\ge0\).
Set
\[
 b_*=2^{q+w},\qquad
 H_*=\frac{4b_*d}{\varepsilon^2\sqrt p},
 \qquad
 h=2^m,\quad m=\ceil{\log_2H_*}.
\]
Let the vault have \(n=\ell+m\) qubits and declare
\[
 k_*=n-(q+w),\qquad K=n-q.
\]
Then \(0\le k_*\le K<n\), there are \(w+1\) retained cuts,
and with Haar probability at least \(1-p\) all those cuts have
full-code recovery error at most \(\varepsilon\).
The cutoff retains \(q\) physical vault qubits.

At the first retained cut,
\begin{align}
 \frac{4d^2}{\varepsilon^2\sqrt p}
 &\le r_*<
 \frac{8d^2}{\varepsilon^2\sqrt p},
 \label{eq:rwindow}\\
 \dim R_*=\frac{dh^2}{b_*}
 &<
 \frac{64b_*d^3}{\varepsilon^4p}.
 \label{eq:receivercost}
\end{align}
\end{theorem}

\begin{proof}
The choice of \(h\) gives \(H_*\le h<2H_*\).
In particular \(dh/b_*\ge4d^2/(\varepsilon^2\sqrt p)\);
hence \(k_*\) is a valid nonnegative integer and
Theorem~\ref{thm:threshold} applies.
Nested release reaches residual dimension \(2^q\) at \(K\).
Substitution proves \eqref{eq:rwindow}--\eqref{eq:receivercost}.
\end{proof}

For fixed \(b_*\) and \(p\), this construction uses
\[
 h=O(d/\varepsilon^2),\quad
 r_*=O(d^2/\varepsilon^2),\quad
 \dim R_*=O(d^3/\varepsilon^4).
\]
The logarithms of these dimensions count qubits.
A polynomial Hilbert-space dimension does not imply a polynomial
algorithm in the payload qubit count \(\ell=\log_2d\).

\subsection{A sufficient certified payload allowance}

For a declared released dimension \(r_*\), rearranging
\eqref{eq:fullthreshold} gives the sufficient range
\begin{equation}
 d\le
 \frac{\varepsilon\,p^{1/4}\sqrt{r_*}}{2f^{1/4}}.
 \label{eq:allowance}
\end{equation}
For qubit payloads, one may choose \(\ell\) with
\(2^\ell\) below this allowance.

Changing \(d\) changes the model or requires an explicitly fixed
larger code. For a single device intended to accept every state
of a smaller subcode, certify the largest declared code once,
then use a fixed isometric subcode embedding and its CPTP
left inverse. Contractivity transfers the same error allowance.
This is not repeated independent certification of arbitrary
unannounced code spaces.

\begin{example}[The threshold is not universally necessary]
With \(U=I\), release the diary \(L\), retain \(H\), and take \(h\ge2\).
Then
\[
 V\ket{\psi}=\ket{\psi}_P\ket{\Phi_h}_{HE},\qquad
 R=PE,\qquad B=H.
\]
Tracing \(E\) is an exact decoder even though \(r=d\).
Consequently the \(d^2\varepsilon^{-2}\) law is not a lower bound
on every operational certificate.
It is the sufficient scaling established for the Haar estimate.
\end{example}

No equation here relates \(d\) to kilograms, physical volume, or
a spacecraft's mechanical complexity.

%=====================================================================
\section{A specified receiver and two storage ledgers}
\label{sec:decoder}
%=====================================================================

\subsection{The decoder program}

Let \(A_*=\dim R_*\).
Use the unnormalized input-first Choi convention
\[
 J(\Phi)=\sum_{i,j}\kb{i}{j}\otimes\Phi(\kb{i}{j}).
\]
A candidate decoder Choi matrix \(C\) on \(R_*'\otimes L_{\rm out}\)
defines
\[
 \Dchan_C(Y)=\Tr_{R_*'}[(Y^{\mathsf T}\otimes I_L)C].
\]
Let
\[
 J_\Delta(C)=J(\Dchan_C\Nchan_*^U-\id_L).
\]
Specify the receiver by
\begin{equation}
 \begin{array}{ll}
 \text{minimize}&t/2\\
 \text{subject to}
 &C\ge0,\quad\Tr_LC=I_{R_*'},\\
 &Z\ge J_\Delta(C),\quad Z\ge-J_\Delta(C),\\
 &\Tr_LZ\le tI_{L'},\quad t\ge0.
 \end{array}
 \label{eq:sdp}
\end{equation}
Among minimizing decoder matrices choose the one of least
squared Frobenius norm, and denote its channel by \(\Dchan_*\).

\begin{proposition}[Deterministic receiver and fixed later policy]
\label{prop:decoder}
Program~\eqref{eq:sdp} defines a unique selected CPTP receiver.
Its objective value is \(\erec(\Nchan_*^U)\).
For \(k\ge k_*\), define
\[
 \Dchan_k=\Dchan_*\Pi_{k\to k_*},
\]
where \(\Pi_{k\to k_*}\) discards the subsequently received cells.
Then
\[
 \Dchan_k\Nchan_k^U=\Dchan_*\Nchan_*^U.
\]
Thus one decoder core supplies all later retained certificates.
\end{proposition}

\begin{proof}
For a Hermiticity-preserving map \(\Delta\), diamond-norm duality
gives
\[
 \norm{\Delta}_\diamond
 =\min\{t: Z\ge\pm J(\Delta),\
             \Tr_{\rm out}Z\le tI_{\rm in}\}
 \cite{WatrousSDP}.
\]
The Choi constraints on \(C\) are exactly CPTP, and composition
is linear in \(C\), proving the objective assertion.

Decoder Choi matrices form a compact convex set; the continuous
error attains its minimum. The minimizing decoder set is convex,
and the strictly convex secondary norm selects a unique matrix.
Finally
\(\Pi_{k\to k_*}\Nchan_k^U=\Nchan_*^U\)
by the stipulated schedule.
\end{proof}

The decoder is selected from the known device matrix, not from
a favorable unknown-input record. The optimization is not reported
as executed.

\subsection{Batch occupancy}

Write
\[
 q_k=\log_2\dim R_k,\qquad q_*=\log_2A_*,
 \qquad \ell=\log_2d.
\]
For qubit dimensions, a decoder of Choi rank \(g\le dA_*\)
has a Stinespring realization with at most
\[
 q_G=\ceil{\log_2g}\le\ell+q_*
\]
environment qubits.

Allocate a fresh output and environment, extend the Stinespring
isometry on its prepared subspace to a unitary, and discard
unused factors. This gives
\begin{equation}
 Q_{\rm lab,peak}\le q_k+\ell+q_G\le q_k+q_*+2\ell.
 \label{eq:workspace}
\end{equation}
The inaccessible active supplier register contains \(n-k\) qubits.
Keeping it separate, the corresponding upper bound on
\emph{live named processing qubits} is
\[
 Q_{\rm named,peak}\le n+m+\ell+q_G.
\]
Neither count includes an untouched test reference, retired physical
record stores, or an unspecified thermal bath.

A useful ledger is therefore
\[
 \mathcal R=
 (Q_{\rm lab,peak},Q_{\rm supplier,active},
 A_{\rm fresh},G_{\rm gates},D_{\rm circuit},
 C_{\rm log},C_{\rm comm},\varepsilon),
\]
with
\[
 A_{\rm fresh}=\ell+q_G,\qquad
 Q_{\rm supplier,active}=n-k.
\]
If discarded decoder factors are implemented by Enter and their
outcomes are retained, an elementary realization records at most
\(q_k+q_G\) such local bits. Its recovery need not send those bits
between sites. Preparation distribution and quantum-cell transport
are separate communication resources.

Arbitrary finite unitaries admit finite decompositions using
continuous one-qubit gates and CNOT \cite{Barenco}.
We do not supply numerical values for \(G_{\rm gates}\) or
\(D_{\rm circuit}\), nor an efficient synthesis algorithm.
The matrix variable \(C\) alone has \((dA_*)^2\) real Hermitian
parameters.

\subsection{Sequential occupancy is a different question}

Reordering operations on disjoint factors can preserve a channel
without preserving the maximum storage occupied during execution.
A finite sequential program must price every arrival, allocation,
retained early register, and workspace factor on every branch.
Branch Kraus maps \(K_\gamma\) must satisfy
\[
 \sum_\gamma K_\gamma^\dagger K_\gamma=I,
\]
and its complete returned channel, not one normalized branch,
must meet the error target.

This is the distinction illustrated in Cheung's batch and streaming
benchmarks \cite{CheungEn02BC}. The batch construction above is
not a streaming optimum.

A Yoshida--Kitaev-type decoder requires its own oracle access,
reflections, success handling, and complexity hypotheses
\cite{YoshidaKitaev}. Neither Haar typicality nor
\eqref{eq:sdp} automatically installs that algorithm.

%=====================================================================
\section{Potential operational functions}
\label{sec:functions}
%=====================================================================

\begin{theorem}[Functions supplied by a recovery certificate]
\label{thm:functions}
Suppose
\[
 \ddiam(\Lambda,\id_L)\le e,\qquad
 \Lambda=\Dchan\Nchan.
\]
Then:
\begin{enumerate}[label=\textup{(\roman*)}]
\item \textbf{Referenced payload return.}
For every state \(\rho_{QL}\),
\[
 \dtr((\id_Q\otimes\Lambda)(\rho_{QL}),\rho_{QL})\le e.
\]

\item \textbf{Entanglement transfer.}
For a Bell input, the decoded Bell overlap satisfies
\[
 \bra{\Phi_d}(\id_Q\otimes\Lambda)
 (\kb{\Phi_d}{\Phi_d})\ket{\Phi_d}\ge1-e.
\]

\item \textbf{Classical message transmission.}
Encoding the \(d\) orthonormal basis messages and measuring the
decoded output in that basis has error at most \(e\) for every
message.

\item \textbf{Logical processing after return.}
For every declared CPTP task \(\mathcal A:L\to T\),
\[
 \ddiam(\mathcal A\Lambda,\mathcal A)\le e.
\]
In particular, any specified logical unitary may be applied after
return without increasing this allowance.

\item \textbf{Measurement-task transfer.}
Every effect \(0\le F\le I\), including a joint
reference--output effect, changes probability by at most \(e\).
A bounded Hermitian observable \(O\) changes expectation by at most
\(2e\norm{O}_\infty\).
\end{enumerate}
\end{theorem}

\begin{proof}
The first assertion is the definition of diamond control.
The Bell projector and each correct-message projector are effects,
which proves the next two assertions.
CPTP postprocessing contracts the diamond norm.
The final claims follow from the operational characterization
of trace distance and trace/operator-norm duality.
\end{proof}

Thus possible functions of the operational construction are a
quantum communication interface, a decoder for stored referenced
information, an entanglement-distribution interface, and an input
wire for subsequent logical processing.
These functions do not require a geometric throat.

\begin{theorem}[Privacy against the complete declared residual]
\label{thm:privacy}
If
\(\ddiam(\Cchan,\rep{\tau_B})\le\zeta\), then
\[
 \dtr((\id_Q\otimes\Cchan)(\rho_{QL}),
                 \rho_Q\otimes\tau_B)\le\zeta
\]
for every referenced input.
For any two unreferenced inputs,
\[
 \dtr(\Cchan(\rho),\Cchan(\sigma))\le2\zeta.
\]
An observer restricted to \(B\), with equal prior probabilities
for these inputs, has discrimination success probability at most
\(1/2+\zeta\).
Arbitrary processing of \(B\) cannot increase these bounds.
\end{theorem}

\begin{proof}
Apply the diamond comparison to \(\rho_{QL}\).
Use the triangle inequality through \(\tau_B\) for the second claim.
For equally likely states, the best success probability is
\((1+\dtr)/2\), giving the third claim.
CPTP contraction proves the last assertion.
\end{proof}

This is privacy against the named complete complement.
It is not a cryptographic security theorem against an adversary
also granted unmodelled receiver data or public transcripts.
Those systems would have to be included in the adversary interface.

\subsection{A beacon is weaker than the payload}

\begin{example}[Readable beacon, unrecoverable code]
The qubit isometry
\[
 V\ket{i}=\ket{i}_R\ket{i}_B
\]
preserves the computational-basis beacon exactly at \(R\),
but both marginal channels dephase.
Their nonconstant complements exclude exact whole-qubit recovery.
\end{example}

\begin{example}[High Bell fidelity need not give uniform accuracy]
\label{ex:phase}
Let
\[
 W=I-2\kb{0}{0},\qquad d\ge2.
\]
The Choi overlap of \(\Ad_W\) with identity is
\[
 \left|\frac{\Tr W}{d}\right|^2=(1-2/d)^2,
\]
which approaches one as \(d\) grows.
Nevertheless
\[
 \norm{\Ad_W-\id}_\diamond=2.
\]
Indeed, \(W\) maps
\((\ket{0}+\ket{1})/\sqrt2\) to an orthogonal state.
Every computational-basis beacon is unchanged.
A decoder applying \(W^\dagger\) repairs the channel, but the
uncorrected receiver has maximal worst-case error.
\end{example}

The distinction is between a specified decoder, an optimal decoder,
a selected test, and a full-code claim
\cite{CheungOai290280}.

A deterministic a posteriori route to full-code certification is a
complete Choi comparison. If a calibrated reconstructed Choi matrix
\(\widehat J\) satisfies
\[
 \norm{\widehat J-\Jn(\Lambda)}_1\le t,
\]
then
\[
 \norm{\Lambda-\id_L}_\diamond
 \le d\bigl(\norm{\widehat J-\kb{\Phi_d}{\Phi_d}}_1+t\bigr).
\]
This follows from the Choi conversion already proved.
Obtaining the calibration allowance \(t\) is an additional
experimental-statistical task, not the observation of one beacon.

%=====================================================================
\section{Entropy predictions and a genuinely scaled turnover theorem}
\label{sec:entropy}
%=====================================================================

Fix a pure payload input \(\ket{\psi}\) independently of \(U\).
After tracing \(E\), the vault state is
\[
 \rho_{\rm vault}^U=h^{-1}UP_\psi U^\dagger,\qquad
 \rank P_\psi=h.
\]
This is generally a mixed random-projector ensemble.
The entropy below is that of late radiation \(P_k\), not
automatically that of the full receiver \(P_kE\).

\begin{lemma}[Late-radiation purity and rank]
\label{lem:entropy}
At a cut \(D=rb\),
\begin{equation}
 \Expect_U\Tr[(\rho_P^U)^2]
 =
 p_{\rm q}(r,b,h)
 :=
 \frac{r(b^2-1)+b(r^2-1)/h}{D^2-1}.
 \label{eq:purity}
\end{equation}
Moreover,
\[
 S(P)\le\log_2\min(r,bh),\qquad
 \Expect_U S(P)\ge-\log_2p_{\rm q}.
\]
\end{lemma}

\begin{proof}
Twirl \(\Swap_{PP'}\otimes I_{BB'}\).
Its identity and full-swap coefficients are
\(r(b^2-1)/(D^2-1)\) and \(b(r^2-1)/(D^2-1)\).
The vault purity is \(1/h\), giving \eqref{eq:purity}.
The global \(PBE\) state is pure, so the \(P\) marginal has
rank at most \(\min(r,bh)\).
Finally \(S(\rho)\ge-\log_2\Tr\rho^2\); Jensen's inequality
gives the mean lower bound.
\end{proof}

The coherent rank envelope balances \(r\) against \(bh\), not
against a classical record alphabet. The pure Page--Sen ensemble
is the specialization \(h=1\), not the general \(h>1\) preparation
\cite{CheungHawk05ABC,CheungHawk07A}.

\begin{theorem}[Scaled turnover with recovery and a one-qubit cutoff]
\label{thm:turnover}
Let
\[
 d=4^s,\qquad s\ge2,\qquad f=1,\qquad h=2^m,\qquad D=dh.
\]
Choose \(\zeta>0\) and
\begin{equation}
 h\ge\frac{2d^2}{\zeta}.
 \label{eq:scaledturnover}
\end{equation}
Declare
\[
 k_*=m+s-1,\quad
 k_{\rm peak}=m+s,\quad
 k_+=m+s+1,\quad
 K=m+2s-1.
\]
A set of Haar devices of measure at least \(1/(4d)\) satisfies:
\begin{enumerate}[label=\textup{(\roman*)}]
\item \(z_k(U)\le\zeta\) for every \(k_*\le k\le K\);
\item one fixed decoder core has half-diamond error at most
\(\min\{a_d,\sqrt{2\zeta}\}\) at every retained cut;
\item for the fixed pure input,
\[
 S(P_{k_{\rm peak}}^U)>
 \log_2(h\sqrt d/2)
 \ge
 \max\{S(P_{k_*}^U),S(P_{k_+}^U),S(P_K^U)\};
\]
\item \(B_K\) is one physical qubit.
\end{enumerate}
The ensemble mean has the same strict peak relative to
\(k_*\) and \(k_+\).
\end{theorem}

\begin{proof}
Write \(t=\sqrt d=2^s\).
The first three cuts have dimensions
\[
 (r_*,b_*)=(ht/2,2t),\quad
 (r_{\rm peak},b_{\rm peak})=(ht,t),\quad
 (r_+,b_+)=(2ht,t/2).
\]
The cutoff has \(b_K=2\).

At the first cut, \eqref{eq:momentbound} gives
\[
 \Expect z_*^2\le d^3/h^2.
\]
Therefore
\[
 \Prob\{z_*>\zeta\}\le\frac{d^3}{h^2\zeta^2}
 \le\frac1{4d}.
\]

At the peak, put \(\mu=ht/2\).
Equation~\eqref{eq:purity} yields
\[
 \mu\,p_{\rm q}(ht,t,h)
 =
 \frac{dh^2(2d-1)-d}{2(d^2h^2-1)}.
\]
Hence
\[
 1-\mu p_{\rm q}
 =
 \frac{dh^2+d-2}{2(d^2h^2-1)}
 >
 \frac1{2d}.
\]
Markov's inequality implies
\[
 \Prob\{\Tr[(\rho_{P_{\rm peak}}^U)^2]<1/\mu\}
 >\frac1{2d}.
\]
On this event, \(S(P_{\rm peak}^U)>\log_2\mu\).
The rank bound at \(k_*\) and \(k_+\) is \(\mu\);
at \(K\) it is \(2h\le\mu\).
Subtracting the possible leakage-failure set leaves measure
greater than \(1/(4d)\).

Nested monotonicity propagates leakage, and
Proposition~\ref{prop:decoder} supplies the common receiver policy.
Also \(p_{\rm q}<1/\mu\), so the mean entropy lower bound is
strictly above \(\log_2\mu\) at the peak.
\end{proof}

\begin{corollary}[Full-diamond version]
\label{cor:scaledturnover}
For \(d=4^s\), \(s\ge2\), and \(0<\varepsilon<1\), it suffices to choose
\[
 \zeta=\varepsilon^2/8,\qquad
 h=2^m\ge\frac{16d^2}{\varepsilon^2}.
\]
Then the family in Theorem~\ref{thm:turnover} has full-diamond
error at most \(\varepsilon\) on all retained cuts.
For \(d=16\), its measure allowance is \(1/64\).
For larger \(d\), the proved allowance is \(1/(4d)\), not a
dimension-independent \(1/64\).
\end{corollary}

This new theorem does not assert turnover for every payload dimension
or every Haar sample. Arbitrary qubit dimensions have the separate
recovery theorem of Section~\ref{sec:scaling}.

\subsection{The album prediction}

For destructive readout in a prescribed basis,
\[
 (\Enter_A\otimes\id_T)(X)
 =
 \sum_y\kb{y}{y}_Y\otimes
       (\bra{y}_A\otimes I_T)X(\ket{y}_A\otimes I_T).
\]
The measured name is consumed; \(T\) survives.

For every fixed process with an append-only record,
\begin{equation}
 H(Y_{\le k+1})=
 H(Y_{\le k})+H(Y_{k+1}\mid Y_{\le k})
 \ge H(Y_{\le k}).
 \label{eq:album}
\end{equation}
This is the classical chain rule, including adaptive readout.
It concerns the unedited record of one process, not a selected
subsequence or a reset memory.

Thus coherent entropy may rise and fall while the album cannot.
Neither curve determines recovery by itself
\cite{CheungHawk05ABC}.
In the nested model, leakage and optimal recovery error remain
nonincreasing through the coherent peak.

%=====================================================================
\section{Convoys, relays, and the reset condition}
\label{sec:convoy}
%=====================================================================

\subsection{Independent stock-prepared sessions}

A finite convoy is a new model with payloads
\(L_1,\ldots,L_N\), independent resource factors
\(H_iE_iF_i\), specified unitary devices, declared release interfaces,
and fresh decoder workspaces. The payloads themselves need not
be independent: they may be mutually entangled and entangled with
one external reference.

\begin{theorem}[Finite convoy with arbitrary joint input]
\label{thm:convoy}
For session \(i\), suppose the complete preparation is independent
of all payloads and other session resources, and its decoded
channel satisfies
\[
 \ddiam(\Lambda_i,\id_{L_i})\le e_i.
\]
Suppose the actual independent-session output channel is
\(\bigotimes_i\Lambda_i\). Then
\begin{equation}
 \ddiam\left(\bigotimes_{i=1}^N\Lambda_i,
                  \id_{\bigotimes_iL_i}\right)
 \le\min\left\{1,\sum_{i=1}^Ne_i\right\}.
 \label{eq:convoy}
\end{equation}
The bound preserves every joint payload--reference correlation.

If session \(i\)'s device event has probability at least \(1-p_i\),
all session certificates hold jointly with probability at least
\(1-\sum_i p_i\), when this lower bound is positive.
Device-event independence is unnecessary for this assertion.
\end{theorem}

\begin{proof}
Replace the tensor factors by identity one at a time.
Each difference has diamond norm at most \(2e_i\), since the
remaining tensor factors are channels of diamond norm one.
The triangle inequality proves \eqref{eq:convoy}.
Its diamond formulation already includes mutually entangled inputs.
The probability statement is the union bound.
\end{proof}

The tensor-product hypothesis is supplied by the newly declared
independent resources and noninteracting session operations.
It is not inferred from good marginal tests.

\begin{corollary}[One selected design used on fresh copies]
\label{cor:identicalconvoy}
Fix \(N\), payload dimension \(d=2^\ell\), total full-diamond
allowance \(0<\varepsilon<1\), and \(0<p<1\).
Use \(N\) fresh copies of the same resource and port design.
Select one device matrix \(U\) certified to per-session
full-diamond error \(\varepsilon/N\).
Then the same decoder core can be used separately in all sessions,
and the convoy's joint full-diamond error is at most \(\varepsilon\).

A sufficient per-session released dimension is
\[
 r_*\ge\frac{4d^2N^2}{\varepsilon^2\sqrt p}.
\]
At first retained residual dimension \(b_*\), \(f=1\), it suffices to take
\[
 h\ge\frac{4b_*dN^2}{\varepsilon^2\sqrt p},
\]
rounded upward to a power of two.
The device-selection probability is at least \(1-p\), not a
fresh input-outcome probability for each ship.
\end{corollary}

\begin{proof}
Apply Theorem~\ref{thm:threshold} with per-session target
\(\varepsilon/N\), and Theorem~\ref{thm:convoy} with
\(e_i=\varepsilon/(2N)\).
The same device property applies to every identically prepared
copy; it need not be resampled.
\end{proof}

This construction consumes \(N\log_2h\) Bell pairs in total.
It does not show that one Bell resource or one unreset vault
serves \(N\) payloads. Its \(N^2\) allowance is a sufficient
finite joint-error budget, not an asymptotic capacity or throughput
optimum.

Laboratory occupancy depends on whether the sessions run in
parallel or sequentially. The total stock of resource halves,
retained outputs, supplier holdings, and workspaces must remain
in the separate storage ledger.

\subsection{A sufficient memory-reuse theorem}

Memory channels require a stronger contract than an isolated
single-use channel \cite{KretschmannWernerMemory}.

\begin{theorem}[Complete session-and-reset composition]
\label{thm:resetcomposition}
Let \(M\) be a reusable device memory, and fix its specified reset
state \(\omega_M\).
For session \(i\), let
\[
 \Fchan_i:\BB(L_iM)\to\BB(L_i'M)
\]
be the complete returned session map, including its receiver and
reset action. Suppose, on the entire joint input space,
\begin{equation}
 \ddiam(\Fchan_i,\id_{L_i}\otimes\rep{\omega_M})\le u_i.
 \label{eq:memorycontract}
\end{equation}
Previous returned payloads are isolated from later device operations.
Then, for any initial memory and any joint payload--reference state,
the final returned payloads and memory differ from ideal identity
return with fixed \(\omega_M\) by half-diamond error at most
\[
 \min\left\{1,\sum_i u_i\right\}.
\]
\end{theorem}

\begin{proof}
Insert untouched identity wires for prior outputs and future inputs.
Replace each actual session by
\(\id_{L_i}\otimes\rep{\omega_M}\), one at a time.
All maps before and after a replacement are channels, so
diamond contraction bounds the replacement by \(u_i\).
The ideal sequence returns each payload unchanged and resets
the memory. Sum the bounds.
\end{proof}

Condition~\eqref{eq:memorycontract} includes memory correlations
with all untouched systems. It is stronger than testing the device
only when \(M=\omega_M\).

One explicit realization is to discard the old processing memory
into an accounted-for environment, prepare a fresh independent
resource, perform a certified session, and prepare the designated
output memory state. That is resource replacement, not a free
cyclic reset. No physical thermal cost follows until an
implementation is specified \cite{CheungEn07A}.

\begin{example}[Why low leakage is not a freshness theorem]
Consider an exact first-session interface
\[
 V\ket{\psi}=\ket{\psi}_A\ket{\Phi_h}_{SM},
 \qquad R=AS,\quad B=M.
\]
The logical complement is replacement and has zero leakage.
Nevertheless \(M\) is correlated with \(S\).

If \(S\) is discarded after returning \(A\), then the accessible
resource \(\Phi_{SM}\) is gone. The remaining marginal \(I_M/h\)
does not restore it. A proposed second teleportation session cannot
replace a missing receiver half by the fact that this marginal
is unchanged.

More generally, a Bell state on \(QM\) and the product state
\(I_Q/h\otimes I_M/h\) have identical \(M\) marginals but trace
distance \(1-h^{-2}\).
Marginal equality does not establish a reference-preserving reset.
\end{example}

\subsection{Serial relays}

If a single payload is sent through successive specified decoded
links \(\Lambda_j:L\to L\), then
\[
 \ddiam(\Lambda_J\cdots\Lambda_1,\id_L)
 \le\min\{1,\sum_j\ddiam(\Lambda_j,\id_L)\}.
\]
The proof is the same telescoping argument.
Every link still needs its own resource, access, and delay ledger.
This licenses a declared quantum network, not a geometric shortcut.

%=====================================================================
\section{Hybrid communication and causal limitations}
\label{sec:hybrid}
%=====================================================================

\begin{proposition}[Purely classical return has a permanent floor]
\label{prop:classical}
If the entire returned interface is classical, every deterministic
decoder has
\[
 \ddiam(\Dchan\Mchan,\id_L)\ge1-\frac1d.
\]
The full-diamond floor is \(2(1-1/d)\).
\end{proposition}

\begin{proof}
A decoder of a classical channel is measure-and-prepare and hence
entanglement breaking \cite{EntanglementBreaking}.
The Bell-input output is separable.
A product vector has Bell squared overlap at most \(1/d\);
convexity gives the same bound for a separable state.
Testing the Bell projector proves the claim.
\end{proof}

This is an obstruction for an album-only interface.
It cannot be applied to a record plus a surviving quantum receiver
without checking that combined channel
\cite{CheungHawk05ABC,CheungEm03AF}.

\begin{theorem}[An exact hybrid function: teleportation]
\label{thm:teleport}
For \(d=2^\ell\), prepare \(\ell\) Bell pairs \(HE\) before the unknown
payload. A Bell transform on \(LH\), followed by Enter, implements
\[
 \Mchan(X)=
 \frac1{d^2}\sum_{z=1}^{d^2}
       \kb{z}{z}_Y\otimes W_zXW_z^\dagger,
\]
where \(W_z\) are Pauli corrections.
The receiver
\[
 \Dchan(Z)=\sum_zW_z^\dagger
    (\bra{z}_Y\otimes I_E)Z(\ket{z}_Y\otimes I_E)W_z
\]
satisfies \(\Dchan\Mchan=\id_L\), including every reference.
Before \(Y\) arrives, the receiver's channel is
\[
 X\longmapsto\Tr(X)I_E/d.
\]
The communicated label has \(2\ell\) classical bits.
\end{theorem}

\begin{proof}
The coherent Bell expansion is
\[
 \ket{\psi}\longmapsto
 \frac1d\sum_z\ket{z}\,W_z\ket{\psi}.
\]
Destructive readout gives the displayed hybrid channel.
Conditional correction returns every matrix unit.
Forgetting the label averages the \(d^2\) Pauli conjugations,
which is depolarization.
\end{proof}

This is the standard entanglement-assisted protocol
\cite{Teleportation}, not transmission of an unknown state
by classical records alone.
A complete readout dilation retains a copy of the label in
the unreturned environment. A fixed spectator qubit may be
included in that complete residual without changing recovery.

\begin{proposition}[Entanglement alone cannot signal]
\label{prop:nosignal}
For every bipartite state and every CPTP local operation,
\[
 \Tr_A[(\Lambda_A\otimes\id_B)(\rho_{AB})]=\Tr_A\rho_{AB}.
\]
\end{proposition}

\begin{proof}
For a \(B\)-observable \(Z\), the adjoint pullback is
\(\Lambda_A^*(I_A)\otimes Z=I_A\otimes Z\).
Thus all receiver expectations agree.
\end{proof}

The early Bell resource does not communicate a later input choice.
In the hybrid protocol the label, and in the coherent Haar model
the released quantum cells, are the required communication.

\subsection{A supplied schedule bounds influence}

Let a finite site system have, at each tick \(j\), a partition
\(\mathcal P_j\) and a product of block channels.
For terminal region \(Y\), define
\[
 N_{t,t}(Y)=Y,\qquad
 N_{s,t}(Y)=
 \bigcup\{B\in\mathcal P_{s+1}:B\cap N_{s+1,t}(Y)\ne\varnothing\}.
\]
An adjoint channel on a disjoint block preserves the identity.
Backward induction therefore proves
\[
 (\Phi_{s+1}^*\circ\cdots\circ\Phi_t^*)(\mathcal A(Y))
 \subseteq\mathcal A(N_{s,t}(Y)).
\]
If a supplied metric gives every block diameter at most \(\Delta\),
the triangle inequality gives
\[
 N_{s,t}(Y)\subseteq
 \{x:\operatorname{dist}(x,Y)\le(t-s)\Delta\}.
\]
These statements require no initially unentangled state
\cite{CheungEn05}.

A supplied tick duration \(\tau\) gives an envelope
\(c_{\rm sched}=\Delta/\tau\).
The value is an input to the architecture, not a speed derived
from entanglement. A payload-independent routed circuit can preserve
complete instruments while retaining this independently declared
schedule \cite{CheungEn06B}.

Even with fixed block sizes, a larger payload can require more
packets, more parallel wires, or longer serialization.
``The schedule speed is unchanged'' is not a theorem that total
latency or throughput is independent of payload size.

Rescaling the supplied distances and tick durations leaves the
channel diagram unchanged. Scheduler consistency consequently
does not select a Lorentz metric or a proper travel time
\cite{CheungEn08A}.

%=====================================================================
\section{Noise, approximation, and reserved error headroom}
\label{sec:noise}
%=====================================================================

\begin{theorem}[Transfer of the same specified receiver]
\label{thm:noise}
Suppose, after access-preserving identifications,
\[
 \ddiam(\Vchan_{\rm act},\Vchan_{\rm ideal})\le\eta,\qquad
 \ddiam(\Dchan_{\rm imp},\Dchan_{\rm ideal})\le\iota,
\]
and the ideal decoded error is at most \(e\).
Then
\begin{equation}
 \ddiam(\Dchan_{\rm imp}\Nchan_{\rm act},\id_L)
 \le\min\{1,e+\eta+\iota\}.
 \label{eq:noise}
\end{equation}
If the complete ideal complement is within \(\zeta\) of replacement,
the actual complete complement has leakage at most
\(\min\{1,\zeta+\eta\}\), provided the comparison includes its
full residual.
\end{theorem}

\begin{proof}
Partial trace contracts the complete-channel comparison.
Insert the ideal accessible channel and ideal decoder in the
triangle inequality, and apply CPTP contraction.
Apply the same argument to the complete complementary output and
the specified ideal replacement state.
\end{proof}

A noisy returned channel need not itself be an isometry.
Its operational report should therefore retain the ideal certificate
and its comparison allowance, or supply a complete dilation including
the noise environment. Omitting that environment does not establish
actual complete-residual privacy.

\begin{corollary}[Noise-budgeted threshold]
\label{cor:noisethreshold}
Fix full target \(0<\varepsilon<1\), and reserve
\(\eta+\iota<\varepsilon/2\).
Put
\[
 u=\varepsilon/2-\eta-\iota>0,\qquad
 \zeta=u^2/2.
\]
A sufficient Haar threshold for the same receiver to meet the
implemented full-diamond target is
\begin{equation}
 r_*\ge\frac{d^2\sqrt f}{u^2\sqrt p}.
 \label{eq:noisethreshold}
\end{equation}
\end{corollary}

\begin{proof}
The threshold gives ideal half-diamond error
\(\sqrt{2\zeta}=u\). Equation~\eqref{eq:noise} then gives
implemented half-diamond error at most \(\varepsilon/2\).
\end{proof}

For a finite circuit, replacing individual complete gates or
instruments with half-diamond errors \(\gamma_v\) gives a total
allowance at most \(\sum_v\gamma_v\), by replacing them one at a time.
One must include preparation, controls, stored memory, propagation,
and readout where they are actually approximated.

Finite-dimensional entropy and the channel diagnostics are continuous
in the device matrix. In particular,
\[
 \ddiam(\Ad_U,\Ad_{U'})\le\norm{U-U'}_\infty.
\]
The bound follows by expanding
\(U\rho U^\dagger-U'\rho(U')^\dagger\) into two differences,
also with references.
A successful device chosen with strict leakage headroom and a
strict entropy gap therefore has sufficiently accurate finite
approximations preserving those inequalities.

This is an existence and stability statement.
No Haar circuit, decoder matrix, gate approximation, or successful
compiler execution is supplied.

%=====================================================================
\section{Terminal discard, reset, and nongeometric costs}
\label{sec:discard}
%=====================================================================

\begin{proposition}[Residual readout does not retract the return]
\label{prop:discard}
For the declared residual factor,
\[
 \Drop\circ\Enter_B=\Tr_B,
\]
including all surviving receiver factors and references.
Thus unreported residual readout followed by forgetting leaves the
already returned accessible channel unchanged.
The same holds for every unreported local CPTP residual operation.
\end{proposition}

\begin{proof}
For
\(X=\sum_{i,j}X_{ij}\otimes\kb{i}{j}_B\),
both operations return \(\sum_iX_{ii}\).
The general statement follows because the local adjoint preserves
\(I_B\).
\end{proof}

An appended residual album obeys \eqref{eq:album}, but need not
describe the payload. Nothing in this proposition moves the payload
back out of the receiver or turns a classical album into its decoder.

If the complete terminal operation is an isometry \(W_B:B\to B'\),
then
\[
 \Cchan'=\Ad_{W_B}\Cchan,\qquad
 \dleak(\Cchan')=\dleak(\Cchan).
\]
The forward inequality is contraction. A CPTP left inverse of the
isometric channel gives the reverse inequality.
The residual may leave the returned address space while remaining
in the complete physical output \cite{CheungEn07A,CheungHawk07A}.

\subsection{There is no fuel bill in the channel alone}

A SWAP with an independent blank implements a reset channel for
every common excitation gap \(\epsilon_{\rm gap}>0\).
For input excitation probability \(p_{\rm ex}\), the energy transfer
is \(\epsilon_{\rm gap}p_{\rm ex}\).
The same observed channel therefore permits different energy ledgers.
The blank is consumed; restoring it is another task
\cite{CheungEn07A,CheungEn07B}.

Accordingly:
\[
 \text{complete reversible encoding},\quad
 \text{residual information leakage},\quad
 \text{heat/work/reset cost}
\]
are different kinds of data.
No \(k_{\rm B}T\ln2\) cost or evasion of a thermal erasure bound is
derived here.

An externally declared law
\[
 \dot M=-\lambda/M^2,\qquad M_{\rm cut}>0,
\]
would give
\[
 t_{\rm cut}-t_0=
 \frac{M_0^3-M_{\rm cut}^3}{3\lambda}.
\]
This is an additional clock, not a relation between \(M\) and
the register dimensions. A supplied temperature is likewise not a
temperature derived for a wormhole
\cite{CheungHawk05ABC,CheungEn07C}.

%=====================================================================
\section{Prediction register and the Hawk07-B theorem}
\label{sec:predictions}
%=====================================================================

\begingroup
\small
\renewcommand{\arraystretch}{1.12}
\begin{longtable}{@{}p{.24\linewidth}p{.39\linewidth}p{.30\linewidth}@{}}
\caption{Operational predictions and their domains.}\\
\toprule
Potential function & Proved conditional prediction & Not supplied\\
\midrule
\endfirsthead
\toprule
Potential function & Proved conditional prediction & Not supplied\\
\midrule
\endhead
\bottomrule
\endfoot

Quantum payload return &
A specified receiver returns all code states and their references
within the diamond allowance after a certified cut. &
A material spacecraft trajectory.
\\[5pt]

Entanglement distribution &
A Bell payload has decoded overlap at least \(1-e\);
arbitrary reference correlations have trace-distance error at most \(e\). &
Entanglement generated by gravity.
\\[5pt]

Private recovery &
The declared complete residual is within \(\zeta\) of an
input-independent channel on every reference extension. &
Security against additional unmodelled access.
\\[5pt]

Logical processing &
Any declared CPTP task after return inherits the same
half-diamond allowance. &
An efficient universal receiver or fault-tolerance theorem.
\\[5pt]

Delayed return &
One decoder core remains available at every later retained cut,
if coherent access is preserved. &
Automatic protection against unbudgeted storage noise.
\\[5pt]

Hybrid communication &
Bell-label Enter plus surviving quantum memory returns the payload
after classical correction. &
Signaling before the label or free resource reuse.
\\[5pt]

Convoys and relays &
Independently prepared sessions or uniformly certified reset
sessions compose with additive diamond allowances. &
Composition inferred from previous small leakage alone.
\\[5pt]

Monitoring and logs &
Every append-only cumulative record has nondecreasing Shannon
entropy. &
An album-only reconstruction of an unknown quantum payload.
\\[5pt]

Termination &
Residual readout-and-forgetting leaves the established accessible
channel unchanged. &
Annihilation, a remnant-free endpoint, or geometric pinch-off.
\\
\end{longtable}
\endgroup

\begin{theorem}[Hawk07-B operational extrapolation and function theorem]
\label{thm:main}
Within the finite preparation, complete-output, and access declarations
of Section~\ref{sec:scaling}, the following conclusions hold.
\begin{enumerate}[label=\textup{(\roman*)}]
\item For any declared qubit payload dimension \(d\), any
\(0<\varepsilon<1\), and any \(0<p<1\), the design in
Theorem~\ref{thm:design} supplies a positive-residual retained window
and a family of Haar devices of measure at least \(1-p\) with one
fixed receiver core and full-diamond error at most \(\varepsilon\).

\item Such a receiver supplies referenced quantum return,
entanglement transfer, classical basis-message transmission,
and post-return logical tasks with the errors in
Theorem~\ref{thm:functions}.
The residual privacy allowance is the separate statement of
Theorem~\ref{thm:privacy}.

\item The sufficient released-dimension law is
\(d^2\varepsilon^{-2}\sqrt{f/p}\), up to the displayed constant,
not the proposed \(d^2\varepsilon^{-1}\sqrt f\).
The complete receiver dimension and batch workspace must additionally
price \(h\).

\item For the square-power family \(d=4^s\), \(s\ge2\), the newly proved
turnover family has measure at least \(1/(4d)\), accurate return
through every retained cut, strict coherent rise-and-fall, and a
final residual consisting of one physical qubit.

\item Finite convoys and serial links are certified under the
independent-resource or complete memory-reset contracts of
Section~\ref{sec:convoy}, including entanglement among payloads.

\item Actual channel and receiver approximations preserve the stated
return target only within the reserved error budget of
Section~\ref{sec:noise}.

\item Purely classical return obeys the entanglement-breaking floor;
hybrid return can avoid it only by retaining its quantum resource.
Append-only records do not turn over.
Terminal residual discard neither retracts a completed return nor
deletes the complete physical complement.

\item No second commuting code-preserving action of the same logical
matrix algebra is produced.
\end{enumerate}
These are operational predictions, not predictions of a spacetime
wormhole, gravitational travel, a quantum extremal surface, a
replica wormhole, a gravitational Page curve, or spacetime emergence.
\end{theorem}

\begin{proof}
The arbitrary-dimension recovery statement follows from the rederived
moment, the threshold theorem, the explicit dimension design, and the
selected receiver program.
The operational functions and residual privacy are proved in
Section~\ref{sec:functions}.
Equation~\eqref{eq:fullthreshold} and the distinction
\(\dim R_*=r_*h\) establish the corrected resource statement.

Theorem~\ref{thm:turnover} proves the new scaled entropy claim.
The tensor-product, memory-reset, and serial telescoping arguments
prove the composition statements.
The noise theorem and its budgeted corollary prove transfer to a
compatible actual receiver.
The classical, teleportation, record-chain-rule, and residual-discard
arguments prove the return-type and endpoint assertions.
Proposition~\ref{prop:noduplicate} proves the algebraic exclusion.

No metric, gravitational stress equation, geometric throat, or
signal-crossing experiment is among the model's declarations.
The excluded physical conclusions are therefore not established
by this theorem.
\end{proof}

\subsection{What a geometric successor must add}

A gravitational use of the word ``wormhole'' would require, in one
identified model:
\begin{enumerate}
\item a metric or justified effective geometry, with the proposed
mouths and throat identified;
\item gravitational equations and justified stress assumptions,
including the relevant energy-condition properties;
\item causal structure and boundary conditions;
\item an injection, propagation, and extraction experiment supporting
a geometric signal-crossing claim;
\item all inaccessible outputs and a physical receiver;
\item quantitative comparisons from the microscopic processes to
the finite channel certificate.
\end{enumerate}

The gravitational constructions in the external literature add
specific couplings and backreaction; an entangled resource alone
does not reproduce them
\cite{GaoJafferisWall,MaldacenaStanfordYang}.
Em03-A's prescribed Schwarzschild emission calculation is a
different fixed-background construction
\cite{CheungEm03AF}.
Neither it nor ER \(=\) EPR identifies the present interface
with a material transport path.

\paragraph{Corrected spacecraft reading.}
If a future model genuinely encoded the relevant spacecraft state,
preserved the required reference correlations, supplied the
communication resources, and implemented the declared receiver,
then the theorem would bound the error of that \emph{logical state
return}. The present paper supplies none of the missing physical
identifications. It cannot predict passenger survival, displacement,
proper time, propulsion energy, or the fate of a gravitational remnant.

\paragraph{Conclusion.}
The extrapolation makes quantitative predictions about information
tasks and their resources. It does not turn the analogy into a
geometry. The ship is a declared code, the passage is a receiver
contract, and the convoy is a separately declared composition.

%=====================================================================
\appendix
\section{Endpoint and documentary separation}
\label{app:separation}
%=====================================================================

The four endpoint obligations remain useful:
complete preparation, complete evolution, declared outgoing access
with access-preserving comparison, and a specified endpoint map
\cite{CheungEn07B}.
They are supplied for the ideal finite sessions here.
A laboratory or gravitational interpretation must supply its own
same-model versions; source vocabulary does not fill those slots.

The supplied XIV-I and XIV-J passages concern a different
characteristic-distribution problem.
Their internal constructions do not establish the complete joint
characteristic map or admit the inherited quantum coefficient.
The supplied XV-B version 2 exists as a technical manuscript with
abstract lifting and extension results; its downstream admission
exit is not thereby opened.
The supplied XVI-N special-family result is not discharged by a
finite decoder \cite{CheungAnalytic}.

The standing documentary scope is unchanged:
\[
 \boxed{
 \begin{gathered}
 O.1=\texttt{NOT\_CLOSED},\\
 \text{XV-B admission exit not opened},\\
 \text{XVI-N not discharged},\\
 \text{no inherited characteristic quantum coefficient admitted}.
 \end{gathered}}
\]
These are scoped status records, not new universal impossibility
theorems.

The supplied OpenAI catalogue and its Families 272, 276, 211, 069,
280, and 265 are documentary comparisons, not mathematical premises
or verified gravitational dictionaries.
A static area-law record does not determine a temporal channel,
a recovery map, or throat area \cite{CheungOai265}.
No catalogue count, current-result status, or formalization claim
is needed for any theorem above.

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

\paragraph{Relation to Hawk07-A.}
The supplied Hawk07-A is the immediate finite-model predecessor.
Its dimension-\(16\) special measure is not silently generalized.
The arbitrary-dimension moment is rederived, and the scaled
turnover and composition statements are proved with new explicit
hypotheses.

\paragraph{Mathematical contribution.}
The manuscript gives corrected sufficient resource scaling, explicit
positive-cutoff designs, a dimension-dependent turnover extension,
operational function bounds, and two different finite composition
contracts. The underlying correction, teleportation, and
diamond-norm tools are established quantum-information theory;
no priority claim is made for them.

\paragraph{Prediction scope.}
All predictions are conditional finite-model statements.
A failed sufficient certificate is not a recovery no-go result.
A successful selected effect is not an unrestricted channel certificate.
A Haar device-selection event is not a heralded transmission event.

\paragraph{Resources and implementation.}
The paper prices dimension and batch occupancy under declared ideal
controls. Gate counts, duration, fuel, thermal reset cost, device
calibration, and efficient decoding remain separately specified
implementation questions.

\paragraph{Sources.}
The philosophy essay and the publisher record for Cheung's Enter
article are distinct from the supplied internal manuscript records.
Internal identifiers and versions do not establish journal
publication, acceptance, or independent proof checking.
All companion-model references are scoped comparisons.

\paragraph{Physical limits.}
No geometric wormhole, metric emergence, exotic-matter requirement,
energy-condition violation, material spacecraft transport,
gravitational endpoint, or quantum-gravity coefficient is constructed.

\paragraph{Verification.}
This source is intended for standalone \texttt{pdflatex}.
No successful compilation, numerical optimization, sampled Haar
experiment, proof-assistant check, independently executed decoder,
referee approval, or acceptance of Hawk07-B is asserted.

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

\bibitem{CheungPhilosophy}
N.~Cheung,
\emph{The Philosophy of Enter: Destructive Readout, Quantum Recovery,
and the Refusal of Identification}.
EntPhil, version 2, introductory essay,
Enter Calculus Companion.
\url{https://enter.grok.me/enter}.
An interpretive map, not a theorem premise.

\bibitem{CheungEnter}
N.~Cheung,
``The Enter Calculus: A Linear Quantum Lambda Calculus with an
Operational Characterization of Measurement.''
\emph{Frontiers in Physics} \textbf{14} (2026).
DOI: \url{https://doi.org/10.3389/fphy.2026.1954943}.
Publisher author name: Ngo Cheung.
The publisher record reports acceptance on 28 September 2026;
no independent verification of its proofs is claimed here.

\bibitem{CheungI}
N.~Cheung,
\emph{Manuscript I}, version 2.
Enter Calculus Companion.
Supplied operational measurement-characterization and
semantic no-cloning passages.

\bibitem{CheungHawk07A}
N.~Cheung,
\emph{Hawk07-A: Existence of Operational Wormhole Certificates:
A finite Enter model with a fixed receiver, nested access,
and a positive-residual cutoff}.
Supplied manuscript \texttt{Hawk07-A.tex},
15 October 2026.
Immediate predecessor; no publication or compilation status is inferred.

\bibitem{CheungHawk04B}
N.~Cheung,
\emph{Hawk04-B}, version 2.
Enter Calculus Companion.
Supplied complete-output restoration, full-code correction,
classical-return, and discard comparisons.

\bibitem{CheungHawk03A}
N.~Cheung,
\emph{Hawk03-A}, version 1.
Enter Calculus Companion.
Supplied encoded-partner and commuting-duplicate logical-algebra
comparisons.

\bibitem{CheungOai290280}
N.~Cheung,
\emph{Oai290-A}, version 1, and
\emph{Oai280-C}, version 1.
Enter Calculus Companion.
Supplied distinctions among full-code, subsystem,
finite-algebra, named-effect, and implemented-decoder targets.

\bibitem{CheungHawk05ABC}
N.~Cheung,
\emph{Hawk05-A}, \emph{Hawk05-B}, and \emph{Hawk05-C},
versions 1 as specified in the supplied records.
Enter Calculus Companion.
Supplied classical-return obstruction, coherent and destructive
entropy comparisons, and conditional capacity-clock extrapolation.
No model-specific result is imported without its hypotheses.

\bibitem{CheungEn02BC}
N.~Cheung,
\emph{En02-B}, version 1, and
\emph{En02-C}, version 1.
Enter Calculus Companion.
Supplied batch decoder and resource vector,
reference-preserving sequential soundness, streaming-memory
distinctions, and postselected decoder interfaces.

\bibitem{CheungEn05}
N.~Cheung,
\emph{En05-A}, version 1, and
\emph{En05-C}, version 1.
Enter Calculus Companion.
Supplied schedule locality, teleportation communication,
and snapshot--adjoint comparison passages.

\bibitem{CheungEn06B}
N.~Cheung,
\emph{En06-B}, version 1.
Enter Calculus Companion.
Supplied payload-independent routing and complete-instrument
preservation on declared schedules.

\bibitem{CheungEn08A}
N.~Cheung,
\emph{En08-A}, version 1.
Enter Calculus Companion.
Supplied distinction between scheduler consistency and
additional Lorentz-cone representation hypotheses.

\bibitem{CheungEn07A}
N.~Cheung,
\emph{En07-A}, version 1.
Enter Calculus Companion.
Supplied complete residual bookkeeping,
readout-and-forgetting identity, and thermodynamic
underdetermination.

\bibitem{CheungEn07B}
N.~Cheung,
\emph{En07-B}, version 1.
Enter Calculus Companion.
Supplied four same-model endpoint obligations,
oppositely directed recovery inequalities, and
separate thermodynamic ledgers.

\bibitem{CheungEn07C}
N.~Cheung,
\emph{En07-C}, version 1.
Enter Calculus Companion.
Supplied thermal-spectrum and complete-interface distinctions.
Not a wormhole-temperature derivation.

\bibitem{CheungEm03AF}
N.~Cheung,
\emph{Em03-A}, version 1, and
\emph{Em03-F}, version 1.
Enter Calculus Companion.
Supplied fixed-background scalar emission law and
separately specified entanglement-breaking packet obstruction.
Not a microscopic spacetime-wormhole model.

\bibitem{CheungOai265}
N.~Cheung,
\emph{Oai265-A}, version 2.
Enter Calculus Companion.
Supplied separation of static area-law records from recovery,
temporal radiation histories, and geometric identifications.

\bibitem{CheungAnalytic}
N.~Cheung,
\emph{XIV-I}, version 1; \emph{XIV-J}, version 1;
\emph{XV-B}, version 2; and \emph{XVI-N}, version r12.
Enter Calculus Companion.
Supplied internal-amplitude, characteristic-map, lifting-interface,
quantum-admission, and conditional-obstruction status records.
These analytic programmes are not inputs to the finite channel proofs.

\bibitem{KnillLaflamme}
E.~Knill and R.~Laflamme,
``Theory of quantum error-correcting codes.''
\emph{Physical Review A} \textbf{55} (1997), 900--911.
DOI: \url{https://doi.org/10.1103/PhysRevA.55.900}.
Preprint: \url{https://arxiv.org/abs/quant-ph/9604034}.

\bibitem{KSW}
D.~Kretschmann, D.~Schlingemann, and R.~F.~Werner,
``The information-disturbance tradeoff and the continuity of
Stinespring's representation.''
\emph{IEEE Transactions on Information Theory}
\textbf{54} (2008), 1708--1717.
DOI: \url{https://doi.org/10.1109/TIT.2008.917696}.
\url{https://arxiv.org/abs/quant-ph/0605009}.

\bibitem{WatrousBook}
J.~Watrous,
\emph{The Theory of Quantum Information}.
Cambridge University Press, 2018.
Author's manuscript:
\url{https://cs.uwaterloo.ca/~watrous/TQI/TQI.pdf}.

\bibitem{WatrousSDP}
J.~Watrous,
``Simpler semidefinite programs for completely bounded norms.''
\emph{Chicago Journal of Theoretical Computer Science}
\textbf{2013}, article 8.
\url{https://arxiv.org/abs/1207.5726}.

\bibitem{Barenco}
A.~Barenco, C.~H.~Bennett, R.~Cleve, D.~P.~DiVincenzo,
N.~Margolus, P.~Shor, T.~Sleator, J.~A.~Smolin, and H.~Weinfurter,
``Elementary gates for quantum computation.''
\emph{Physical Review A} \textbf{52} (1995), 3457--3467.
DOI: \url{https://doi.org/10.1103/PhysRevA.52.3457}.
\url{https://arxiv.org/abs/quant-ph/9503016}.

\bibitem{HaydenPreskill}
P.~Hayden and J.~Preskill,
``Black holes as mirrors: quantum information in random subsystems.''
\emph{Journal of High Energy Physics}
\textbf{2007}(09), 120.
DOI: \url{https://doi.org/10.1088/1126-6708/2007/09/120}.
\url{https://arxiv.org/abs/0708.4025}.

\bibitem{YoshidaKitaev}
B.~Yoshida and A.~Kitaev,
\emph{Efficient decoding for the Hayden--Preskill protocol}.
arXiv:1710.03363.
\url{https://arxiv.org/abs/1710.03363}.
External decoder construction with its own access and algorithmic
hypotheses.

\bibitem{KretschmannWernerMemory}
D.~Kretschmann and R.~F.~Werner,
``Quantum channels with memory.''
\emph{Physical Review A} \textbf{72} (2005), 062323.
DOI: \url{https://doi.org/10.1103/PhysRevA.72.062323}.
\url{https://arxiv.org/abs/quant-ph/0502106}.

\bibitem{EntanglementBreaking}
M.~Horodecki, P.~W.~Shor, and M.~B.~Ruskai,
``Entanglement breaking channels.''
\emph{Reviews in Mathematical Physics}
\textbf{15} (2003), 629--641.
DOI: \url{https://doi.org/10.1142/S0129055X03001709}.
\url{https://arxiv.org/abs/quant-ph/0302031}.

\bibitem{Teleportation}
C.~H.~Bennett, G.~Brassard, C.~Cr\'epeau, R.~Jozsa,
A.~Peres, and W.~K.~Wootters,
``Teleporting an unknown quantum state via dual classical and
Einstein--Podolsky--Rosen channels.''
\emph{Physical Review Letters} \textbf{70} (1993), 1895--1899.
DOI: \url{https://doi.org/10.1103/PhysRevLett.70.1895}.

\bibitem{MaldacenaSusskind}
J.~Maldacena and L.~Susskind,
``Cool horizons for entangled black holes.''
\emph{Fortschritte der Physik} \textbf{61} (2013), 781--811.
DOI: \url{https://doi.org/10.1002/prop.201300020}.
\url{https://arxiv.org/abs/1306.0533}.

\bibitem{GaoJafferisWall}
P.~Gao, D.~L.~Jafferis, and A.~C.~Wall,
``Traversable wormholes via a double trace deformation.''
\emph{Journal of High Energy Physics}
\textbf{2017}(12), 151.
DOI: \url{https://doi.org/10.1007/JHEP12(2017)151}.
\url{https://arxiv.org/abs/1608.05687}.

\bibitem{MaldacenaStanfordYang}
J.~Maldacena, D.~Stanford, and Z.~Yang,
``Diving into traversable wormholes.''
\emph{Fortschritte der Physik} \textbf{65} (2017), 1700034.
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\url{https://arxiv.org/abs/1704.05333}.

\end{thebibliography}

\end{document}