Proof of `Closure theorem for tuples`
groundedproofs/Lax185574Proofs/ClosureTheoremTuples.lean · lax-185574
What this proof establishes
Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.
In the paper
- page 28 of this submission's paper
Description
Apply the closure theorem at radius to obtain and the sets . For every of size at most , the partition-metric conversion applied to , which has at most parts, gives one flip whose radius- balls lie in the radius- balls of the flip metric of . For a tuple outside take . As refines , the flip metric of dominates that of , and the latter is at least the distance in the -flip from the closure theorem, which exceeds . So separates from at distance more than . There are at most sets .
The argument is carried out for the graph classes of the archive and their monadic dependence, and transferred to the graph classes used here.