didericis
464c524fa1
Paper: - Lemmas 3.4 (exactly one match) and 3.5 (all-distinct exists for 4-colourable G) replace the earlier conjecture; both have proofs. - Add Conjecture 3.6: every proper 3-edge-colouring of a counterexample's reduced dual has a face with two same-colour edges that share a Kempe cycle with the merged edge, neither of them being the merged edge. Experiments (all under experiments/): - search_conj_3_6_counterexample.py: finds n=14 tri#1 i_red=0 where the algorithm's phi_t* sits in a Kempe class with no all-distinct colouring (disproves an earlier formulation). - check_kempe_class.py / check_kempe_class_invariance.py / check_kempe_class_monotone.py: Kempe-class counts on H_1 and H_t* for small triangulations; neither monotonicity direction holds. - check_all_distinct_exists.py: even in the conj-3.6 disproof case, H_t* itself admits all-distinct colourings in the *other* Kempe class. - check_constrained_feasibility.py: literal H_t*-interpretation of C1 + K0 + K1 is empirically unsatisfiable (gap in proof strategy noted). - check_conj_face_kempe.py / check_conj_face_kempe_n15.py: test Conj 3.6 on chord-apex+Kempe colourings of reduced duals at n=12, 14, 15; 216/216 colourings on n=14 satisfy the conjecture, others vacuous. - draw_step1_conj36.py: figure showing a Conj 3.6 witness on H_1 with two new vertices on the witness edges and a new red bridge between them. - draw_step1_conj36_recolored.py: same but with the Kempe cycle recoloured alternately from merged so propriety holds. - draw_lift_to_Gprime.py: lifts the modified+recoloured H_1 back to a proper 3-edge-colouring of the modified G' (24+2 vertices, 39 edges, same Tutte layout as figure 3's first graphic so positions line up). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
math-research
Personal mathematics research repository by Eric Bauerfeld. Papers are written in AMS-LaTeX using the amsart document class.
Papers
kempe_style_search_for_smaller_contradiction
Humans Suffice: A Novel Proof of the Four Color Theorem
An in-progress proof of the Four Color Theorem via a minimal counterexample argument. The paper builds on Kempe's 1879 strategy — establishing valid cases for vertices of degree ≤ 4, then extending the argument to the degree-5 case using properties of non-adjacent degree-5 vertices, merged subgraphs, and locked colorings.
plane_depth_labelling
Plane Depth Labelling
Early-stage paper. Title and author information set; content in progress.
Creating a New Paper
Use run.sh to scaffold a new paper from the AMS-LaTeX template:
./run.sh init_paper "Your Paper Title"
This creates a new directory (name derived from the title) containing a paper.tex pre-filled with the title and author.
Setup
The Python library code in lib/ requires SageMath. Run setup once per machine:
./run.sh setup <sage_python_path> <sage_site_packages> [system_name]
sage_python_path— path to the SageMath Python interpreter (e.g./opt/sage/local/bin/python3)sage_site_packages— path to SageMath's site-packages directorysystem_name— optional label for this machine (defaults tohostname -s); used to store per-machine env files as.env.<system_name>
On subsequent runs the paths default to whatever was saved in .env, so ./run.sh setup alone re-runs setup with the existing configuration.
Setup also compiles the plantri submodule via make.
Running Sage
To run a Sage script with plantri available on PATH:
./run.sh sage <script.py> [args...]
Or to open an interactive Sage session:
./run.sh sage
Linting
./run.sh lint
Runs pyright and pylint on lib/ using the SageMath Python interpreter.
Shell Completion
To enable tab-completion for run.sh in zsh, add this to your .zshrc:
eval "$(path/to/run.sh completion)"
Or source it once in the current shell session:
eval "$(./run.sh completion)"
Building
Papers are compiled with LaTeX. From within a paper directory:
latexmk -pdf paper.tex