Add the freedom-positive counting balance to the constraint floor

Remark: a disk with k interior vertices has 2k+n-2 faces (Euler) but only
k interior constraints, so each interior vertex adds two degrees of
freedom against one constraint -- depth is freedom-positive and Phi can
only retain or enlarge below the interior-free floor 2^(n-2). Motivates
the lower bound and replaces the prior TODO sketch.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
2026-06-17 02:24:04 -04:00
parent b70ea2c087
commit 1d981b4d01
4 changed files with 56 additions and 43 deletions
@@ -35,6 +35,12 @@
\newlabel{conj:heawood-chain-pigeonhole}{{3.8}{5}} \newlabel{conj:heawood-chain-pigeonhole}{{3.8}{5}}
\newlabel{conj:heawood-route-fct}{{3.9}{5}} \newlabel{conj:heawood-route-fct}{{3.9}{5}}
\bibcite{Heawood1898}{1} \bibcite{Heawood1898}{1}
\@writefile{toc}{\contentsline {section}{\tocsection {}{4}{The constraint floor}}{6}{}\protected@file@percent }
\newlabel{sec:constraint-floor}{{4}{6}}
\newlabel{def:achievable-boundary-set}{{4.1}{6}}
\newlabel{prop:constraint-floor}{{4.2}{6}}
\newlabel{rem:freedom-positive}{{4.3}{6}}
\newlabel{rem:floor-consequences}{{4.4}{6}}
\bibcite{bauerfeld-depth}{2} \bibcite{bauerfeld-depth}{2}
\bibcite{bauerfeld-nested-tires}{3} \bibcite{bauerfeld-nested-tires}{3}
\bibcite{bauerfeld-medial-tires}{4} \bibcite{bauerfeld-medial-tires}{4}
@@ -44,10 +50,5 @@
\newlabel{tocindent1}{17.77782pt} \newlabel{tocindent1}{17.77782pt}
\newlabel{tocindent2}{0pt} \newlabel{tocindent2}{0pt}
\newlabel{tocindent3}{0pt} \newlabel{tocindent3}{0pt}
\@writefile{toc}{\contentsline {section}{\tocsection {}{4}{The constraint floor}}{6}{}\protected@file@percent } \@writefile{toc}{\contentsline {section}{\tocsection {}{}{References}}{7}{}\protected@file@percent }
\newlabel{sec:constraint-floor}{{4}{6}} \gdef \@abspage@last{7}
\newlabel{def:achievable-boundary-set}{{4.1}{6}}
\newlabel{prop:constraint-floor}{{4.2}{6}}
\newlabel{rem:floor-consequences}{{4.3}{6}}
\@writefile{toc}{\contentsline {section}{\tocsection {}{}{References}}{6}{}\protected@file@percent }
\gdef \@abspage@last{6}
@@ -1,4 +1,4 @@
This is pdfTeX, Version 3.141592653-2.6-1.40.24 (TeX Live 2022) (preloaded format=pdflatex 2022.10.5) 17 JUN 2026 02:14 This is pdfTeX, Version 3.141592653-2.6-1.40.24 (TeX Live 2022) (preloaded format=pdflatex 2022.10.5) 17 JUN 2026 02:23
entering extended mode entering extended mode
restricted \write18 enabled. restricted \write18 enabled.
%&-line parsing enabled. %&-line parsing enabled.
@@ -203,39 +203,40 @@ ML/cmm/m/it/10 ; ^^U[]\OT1/cmr/m/n/10 (\OML/cmm/m/it/10 v[]\OT1/cmr/m/n/10 ) =
n/10 ) = [][] \OML/cmm/m/it/10 ^^U[]: n/10 ) = [][] \OML/cmm/m/it/10 ^^U[]:
[] []
[6] (./paper.aux) ) [6] [7] (./paper.aux) )
Here is how much of TeX's memory you used: Here is how much of TeX's memory you used:
3021 strings out of 478268 3022 strings out of 478268
42259 string characters out of 5846347 42281 string characters out of 5846347
342330 words of memory out of 5000000 342340 words of memory out of 5000000
21067 multiletter control sequences out of 15000+600000 21068 multiletter control sequences out of 15000+600000
477578 words of font info for 59 fonts, out of 8000000 for 9000 477578 words of font info for 59 fonts, out of 8000000 for 9000
1302 hyphenation exceptions out of 8191 1302 hyphenation exceptions out of 8191
69i,7n,76p,242b,290s stack positions out of 10000i,1000n,20000p,200000b,200000s 69i,7n,76p,242b,362s stack positions out of 10000i,1000n,20000p,200000b,200000s
</usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfo </usr/local/texlive/2022/texmf-dist/fonts/type1/public/a
nts/cm/cmbx10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfon msfonts/cm/cmbx10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/am
ts/cm/cmbx8.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts sfonts/cm/cmbx8.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsf
/cm/cmcsc10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts onts/cm/cmcsc10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsf
/cm/cmex10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/ onts/cm/cmex10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfo
cm/cmmi10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/c nts/cm/cmmi10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfon
m/cmmi5.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/ ts/cm/cmmi5.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts
cmmi7.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cm /cm/cmmi7.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/c
r10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmr5 m/cmr10.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/
.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmr7.pf cmr5.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmr
b></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmr8.pfb>< 7.pfb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmr8.p
/usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmss10.pfb></ fb></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmss10.pf
usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmss8.pfb></us b></usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmss8.pfb>
r/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy10.pfb></usr </usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy10.pfb><
/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy5.pfb></usr/l /usr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy5.pfb></u
ocal/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy7.pfb></usr/loc sr/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmsy7.pfb></usr
al/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmti10.pfb></usr/loca /local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmti10.pfb></usr/
l/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmti8.pfb></usr/local/ local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/cm/cmti8.pfb></usr/lo
texlive/2022/texmf-dist/fonts/type1/public/amsfonts/symbols/msam10.pfb></usr/lo cal/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/symbols/msam10.pfb></us
cal/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/symbols/msbm10.pfb> r/local/texlive/2022/texmf-dist/fonts/type1/public/amsfonts/symbols/msbm10.pfb>
Output written on paper.pdf (6 pages, 266448 bytes).
Output written on paper.pdf (7 pages, 267867 bytes).
PDF statistics: PDF statistics:
123 PDF objects out of 1000 (max. 8388607) 128 PDF objects out of 1000 (max. 8388607)
74 compressed objects within 1 object stream 78 compressed objects within 1 object stream
0 named destinations out of 1000 (max. 500000) 0 named destinations out of 1000 (max. 500000)
1 words of extra memory for PDF output out of 10000 (max. 10000000) 1 words of extra memory for PDF output out of 10000 (max. 10000000)
@@ -499,12 +499,23 @@ the boundary sequence, so the map $\lambda \mapsto \lambda^{*}|_C$ is
injective and $|\Phi(D)| = 2^{\,n-2}$. injective and $|\Phi(D)| = 2^{\,n-2}$.
\end{proof} \end{proof}
%% TODO (lower bound): show |Phi(D)| >= 2^{n-2} for EVERY triangulated \begin{remark}[Depth is freedom-positive]
%% disk D. Strategy: the n boundary-incident faces (one per boundary edge) \label{rem:freedom-positive}
%% carry n-2 independent binary degrees of freedom after the interior The lower bound is plausible from a counting balance. A triangulated
%% Heawood constraints are imposed; those constraints relate only disk with $k$ interior vertices has $2k + n - 2$ faces (Euler) and
%% interior-incident faces and cannot collapse the boundary freedom below imposes exactly $k$ interior Heawood constraints, one per interior
%% 2^{n-2}. (See notes/boundary_restriction_structure.tex.) vertex. So each interior vertex contributes \emph{two} faces --- two new
$\{+1,-1\}$ degrees of freedom --- against only \emph{one} constraint,
and the free dimension $(2k + n - 2) - k = k + n - 2$ \emph{grows} with
depth. Going deeper is freedom-positive on balance: the boundary
projection $\Phi(D)$ can only retain or enlarge its options, never drop
below the interior-free value $2^{\,n-2}$. (Empirically $|\Phi(D)|$ does
grow with $k$; e.g.\ on the $4$-cycle the central-apex wheel realises $5$
sequences against the fan's $4$.) The constraints relate only
interior-incident faces and cannot collapse the $n-2$ degrees of freedom
carried by the boundary-incident faces --- which is the content the lower
bound must make precise.
\end{remark}
\begin{remark} \begin{remark}
\label{rem:floor-consequences} \label{rem:floor-consequences}