Abstract
The commutator subgroup SL(2, Z)' plays a particular role in the Markoff theory since every Markoff number is 1/3 of the trace of same elements of SL(2, Z)'. The latter is a free group with two generators. We give an exhaustive description of the possible pairs of generators of SL(2, Z)', including important new results.
REFERENCES
A. Markoff, “Sur les formes quadratiques binaires indéfinies,” Math. Ann. 15, 381–406 (1879). https://doi.org/10.1007/BF02086269
A. Markoff, “Sur les formes quadratiques binaires indéfinies (séecond mémoire),” Math. Ann. 17, 379–399 (1879). https://doi.org/10.1007/BF01446234
P. Bachmann, Die Arithmetik der quadratischen Formen (B. G. Teubner, Leipzig, 1923).
L. E. Dickson, Studies in hte Theory of Numbers (Chicago Univ. Press, Chicago, 1930).
T. W. Cusick and M. E. Flahive, The Markoff and Lagrange Spectra, AMS Math. Surveys Monographs, Vol. 30 (AMS, Providence, R.I., 1989).
S. Perrine, La théorie de Markoff et ses développement (Tessier & Ashpool, 2002).
M. Aigner, Markov’s Theorem and 100 Years of the Uniqueness Conjecture: A Mathematical Journey from Irrational Numbers to Perfect Matchings (Springer, Cham, 2013). https://doi.org/10.1007/978-3-319-00888-2
Ch. Reutenauer, From Christoffel Words to Markoff Numbers (Oxford Univ. Press, Oxford, 2018). https://doi.org/10.1093/oso/9780198827542.001.0001
P. Schmutz Schaller, Markoff Theory and Hyperbolic Torus Groups, in preparation.
H. Cohn, “Approach to Markoff’s minimal forms through modular functions,” Ann. Math. 61 (1), 1–12 (1955). https://doi.org/10.2307/1969618
D. S. Gorshkov, “Geometry of Lobachevskii in connection with certain questions of arithmetic,” J. Sov. Math. 16, 788–820 (1981). https://doi.org/10.1007/BF01213890
R. Fricke, “Ueber die Theorie der automorphen Modulgruppen,” Nachr. Ges. Wiss. Göttingen, Math.-Phys. Kl. 1896, 91–101 (1896).
J. Nielsen, Collected Mathematical Papers (Birkhäuser, Boston, 1986).
S. Perrine, “L’interprétation matricielle de la théorie de Markoff classique,” Int. J. Math. Math. Sci. 32, 854739 (2002). https://doi.org/10.1155/S0161171202012875
M. Newman, “The structure of some subgroups of the modular group,” Illinois J. Math. 6, 480–487 (1962). https://doi.org/10.1215/ijm/1255632506
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Paul Schmutz Schaller The Markoff Theory and the Commutator Subgroup SL(2, Z)'. Russ Math. 66, 91–101 (2022). https://doi.org/10.3103/S1066369X22120106
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DOI: https://doi.org/10.3103/S1066369X22120106