nprofile1qy2hwumn8ghj7un9d3shjtnddaehgu3wwp6kyqpqknzsux7p6lzwzdedp3m8c3c92z0swzc0xyy5glvse58txj5e9ztqaufa4k (nprofile…fa4k) nprofile1qy2hwumn8ghj7un9d3shjtnddaehgu3wwp6kyqpqt76as6gjr7pzg0taz40e55smjjegmj89ud7g056aqed90hs7cynsacyu7x (nprofile…yu7x) it's a "combinatorial embedding", i.e. collection of distinguished cycles in the graph, so that every edge appears in exactly two of these cycles.
I am not sure how to pick up a basis for the homology group of the 2-holed donut (the join of 2 tori), which is isomorphic to \(\mathbb{Z}^4\). It seems there is still something to specify - these is a number of topologically inequivalent ways each cycle can be embedded. The distinguished cycles are embedded in the contractible way, but you can't freely move them around the surface, as there are the remaining simple cycles.
Dima Pasechnik 🇺🇦 🇳🇱 /
npub1cc…9rjyc
2025-03-17 01:59:40
in reply to nevent1q…r5pt
Author Public Key
npub1ccsatp4j3q6ajf3z3xcqe34ale74g4jaszrlfkqkp523kgu3n9usf9rjycPublished at
2025-03-17 01:59:40Event JSON
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