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Core decision problems for two-relator groups

Decide the word problem, conjugacy problem, and isomorphism problem for the class of finitely presented groups with two defining relations.

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Background

While Magnus’s methods provide solutions for one-relator groups, analogous algorithms for two-relator groups have proved elusive. Even the finiteness problem and structural classification of finite two-relator groups remain largely unknown.

References

The word problem, conjugacy problem, and isomorphism problem are all open for two-relator groups.

The theory of one-relator groups: history and recent progress (2501.18306 - Linton et al., 30 Jan 2025) in Subsection 8.3 (Two-relator groups)