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A comment on A Non-Constructive Proof of the Four Colour Theorem. Parent comment

Re:A Non-Constructive Proof of the Four Colour Theorem by Phemist on Wednesday December 21, 2022 @02:48PM (#34085490)
so in essence there is an additional constraint, that each touching edge has to be of a given minimal size. Each contiguous "blob" with a given circumference of N * this minimal size, can only connect to at most N other blobs.
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Re:A Non-Constructive Proof of the Four Colour Theorem by ColinWright on Thursday December 22, 2022 @06:09AM (#34092194)
No, there is no minimal size, just that we only consider two regions as being "in contact" and therefore requiring different colours) if they have a shared boundary, and that boundary is of non-zero length.

There is no limit to how many regions can surround and be in contact with a given region, it's just that the shared border that defines "in contact with" must be of non-zero length.

Note also: we are dealing with finite maps. That means that for any given map there will be a shortest boundary for that map, but it doesn't mean there is a minimum constraint.

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