THM0103canonicalv1Extensions Are Omega-Germ Transformers
Hartogs extensions from L to tau^3 are the same as omega-germ transformers: the extension of boundary data through the tower produces precisely the tower-coherent family of stage-k morphisms that defines an omega-germ transformer.
Payload
Extensions Are Omega-Germ Transformers
Hartogs extensions from L to tau^3 are the same as omega-germ transformers: the extension of boundary data through the tower produces precisely the tower-coherent family of stage-k morphisms that defines an omega-germ transformer.
Extensions Are Omega-Germ Transformers
Summary
Hartogs extensions from L to tau^3 are the same as omega-germ transformers: the extension of boundary data through the tower produces precisely the tower-coherent family of stage-k morphisms that defines an omega-germ transformer.
Statement
%
\label{thm:extensions-omega-germs}
There is a canonical bijection
\[
\boxed{%
\left\{\;
\parbox{0.4\linewidth}{\centering
Hartogs extensions $f_\chi$\\
of boundary characters $\chi$\\
{\small(II.T37)}
}
\;\right\}
\;\;\xleftrightarrow{\;\;\sim\;\;}\;\;
\left\{\;
\parbox{0.4\linewidth}{\centering
$\omega$-germ transformers $G$\\
regular at the boundary\\
{\small(I.D45 + regularity)}
}
\;\right\}}
\]
given by:
\begin{enumerate}
\item[\textup{(i)}]
\textbf{Forward.}
$f_\chi \;\longmapsto\; G_{f_\chi}
:= \varprojlim_k f_{\chi,k}$.
Stagewise naturality \textup{(II.L13)}
ensures tower coherence;
bipolar splitting ensures sector independence;
the limit exists and gives a $\mathrm{HolFun}$
\textup{(I.D47)}.
\item[\textup{(ii)}]
\textbf{Converse.}
$G \;\longmapsto\; f_{\chi_G}$,
where $\chi_G = \varprojlim_k (G_k\big|_{R_\tau})$
is the boundary restriction.
Regularity ensures $\chi_G$ is idempotent-supported;
\textup{II.T37} produces the unique extension.
\item[\textup{(iii)}]
\textbf{Inverse property.}
The two maps are mutually inverse:
$G_{f_{\chi_G}} = G$
\textup{(Proposition~\ref{prop:ch49-converse})}
and $f_{\chi_{G_{f_\chi}}} = f_\chi$
\textup{(by uniqueness of the Hartogs extension,
II.T37)}.
\end{enumerate}
\noindent
Moreover, the bijection respects the bipolar decomposition:
\[
G_{f_\chi}
\;=\;
e_+ \cdot G_{f_\chi}^+
\;+\;
e_- \cdot G_{f_\chi}^-,
\]
where $G_{f_\chi}^\pm$
depends only on $\chi_\pm$.
Proof / Justification
The forward direction is
Proposition~\ref{prop:ch49-g-is-holfun}:
$G_{f_\chi}$ is a $\tau$-holomorphic function
(sector-independent and tower-coherent),
hence an $\omega$-germ transformer.
It is regular at the boundary
because its boundary restriction
recovers~$\chi$
(by construction:
$G_{f_\chi}\big|_{R_\tau}
= \varprojlim_k f_{\chi,k}\big|_{R_\tau}
= \chi$,
since $f_\chi$ is the extension of~$\chi$).
The converse direction is
Proposition~\ref{prop:ch49-converse}:
regularity gives $\chi_G$,
II.T37 gives $f_{\chi_G}$,
and II.T27 gives $G_{f_{\chi_G}} = G$.
The inverse property in direction (iii):
starting from $f_\chi$,
we construct $G_{f_\chi}$,
restrict to the boundary to get $\chi_{G_{f_\chi}}$,
and extend again.
The boundary restriction of $G_{f_\chi}$
is~$\chi$ (shown above),
so $\chi_{G_{f_\chi}} = \chi$,
and the extension of~$\chi$ is $f_\chi$ (II.T37 uniqueness).
Hence $f_{\chi_{G_{f_\chi}}} = f_\chi$.
The bipolar decomposition
follows from
Proposition~\ref{prop:ch49-bipolar-stage}
and the fact that the inverse limit
commutes with the idempotent projection
(projections preserve limits).
Source Context
- Registry source:
book-02.jsonlline 144 - Manuscript source:
2nd-edition/book-ii-categorical-holomorphy/02_mainmatter/part09/ch49-extensions-omega-germs.texlines 662-725
Lean / Formalization Notes
- Formalization:
formalized - Module:
TauLib.BookII.CentralTheorem.ExtensionsOmegaGerms - Name:
Tau.BookII.CentralTheorem.omega_germ_transformer_check
Dependencies
- Canonical: II.T37, II.L13, II.T27, II.D37
Related Results
Generated by later projection phases.
Related Publications
Generated by later projection phases.
Revision Notes
- 2026-04-24: Initial pilot migration.
Identifiers
Aliases & legacy IDs
II.T38extensions-are-omega-germ-transformersthm:extensions-omega-germsRelease lines
corpus_v3_workingcorpus_v2Relations
Formalized by (5)
Appears in (1)
Downstream uses (computed) (10)
Items in the corpus that reference this one via load-bearing relations. Computed from the full corpus-v3 graph at build time.
FTH0142formal theorem
FTH0142formal theorem
FTH0143formal theorem
FTH0143formal theorem
FTH0146formal theorem
FTH0146formal theorem
FTH0147formal theorem
FTH0147formal theorem
FTH0148formal theorem
FTH0148formal theoremSources
Version & History
Status disclaimer
A Corpus Item page reports the program's current internal record for this item. It does not imply external verification, scientific consensus, or final proof unless explicitly stated. Read it together with its dependencies, formalization status, and the program's overall stance.