Abstract
In this paper we study decidability and complexity of decision problems on matrices from the special linear group SL\((2,\mathbb {Z})\). In particular, we study the freeness problem: given a finite set of matrices G generating a multiplicative semigroup S, decide whether each element of S has at most one factorization over G. In other words, is G a code? We show that the problem of deciding whether a matrix semigroup in SL\((2,\mathbb {Z})\) is non-free is NP-hard. Then, we study questions about the number of factorizations of matrices in the matrix semigroup such as the finite freeness problem, the recurrent matrix problem, the unique factorizability problem, etc. Finally, we show that some factorization problems could be even harder in SL\((2,\mathbb {Z})\), for example we show that to decide whether every prime matrix has at most k factorizations is PSPACE-hard.
This research was supported by EPSRC grant EP/M00077X/1.
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Bell, P.C., Hirvensalo, M., Potapov, I.: Mortality for \(2\times 2\) matrices is NP-hard. In: Proceedings of the 37th International Symposium on Mathematical Foundations of Computer Science, pp. 148–159 (2012)
Bell, P.C., Hirvensalo, M., Potapov, I.: The identity problem for matrix semigroups in SL\((2,\mathbb{Z})\) is NP-complete (2016). To appear in SODA 17
Bell, P.C., Potapov, I.: Periodic and infinite traces in matrix semigroups. In: Proceedings of the 34th Conference on Current Trends in Theory and Practice of Computer Science, pp. 148–161 (2008)
Bell, P.C., Potapov, I.: Reachability problems in quaternion matrix and rotation semigroups. Inf. Comput. 206(11), 1353–1361 (2008)
Bell, P.C., Potapov, I.: On the undecidability of the identity correspondence problem and its applications for word and matrix semigroups. Int. J. Found. Comput. Sci. 21(6), 963–978 (2010)
Bell, P.C., Potapov, I.: On the computational complexity of matrix semigroup problems. Fundamenta Infomaticae 116(1–4), 1–13 (2012)
Blondel, V.D., Cassaigne, J., Karhumäki, J.: Problem 10.3: freeness of multiplicative matrix semigroups. In: Unsolved Problems in Mathematical Systems and Control Theory, pp. 309–314. Princeton University Press (2004)
Cassaigne, J., Harju, T., Karhumäki, J.: On the undecidability of freeness of matrix semigroups. Int. J. Algebra Comput. 09(03–04), 295–305 (1999)
Cassaigne, J., Nicolas, F.: On the decidability of semigroup freeness. RAIRO - Theor. Inf. Appl. 46(3), 355–399 (2012)
Charlier, E., Honkala, J.: The freeness problem over matrix semigroups and bounded languages. Inf. Comput. 237, 243–256 (2014)
Choffrut, C., Karhumäki, J.: Some decision problems on integer matrices. RAIRO - Theor. Inf. Appl. 39(1), 125–131 (2010)
Elstrodt, J., Grunewald, F., Mennicke, J.: Arithmetic applications of the hyperbolic lattice point theorem. Proc. Lond. Math. Soc. s3–57(2), 239–283 (1988)
García del Moral, M.P., Martín, I., Peña, J.M., Restuccia, A.: SL\((2, \mathbb{Z})\) symmetries, supermembranes and symplectic torus bundles. J. High Energy Phys. 9, 1–12 (2011)
Gawrychowski, P., Gutan, M., Kisielewicz, A.: On the problem of freeness of multiplicative matrix semigroups. Theor. Comput. Sci. 411(7–9), 1115–1120 (2010)
Gurevich, Y., Schupp, P.: Membership problem for the modular group. SIAM J. Comput. 37(2), 425–459 (2007)
Halava, V., Harju, T., Hirvensalo, M.: Undecidability bounds for integer matrices using claus instances. Int. J. Found. Comput. Sci. 18(05), 931–948 (2007)
Klarner, D.A., Birget, J.-C., Satterfield, W.: On the undecidability of the freeness of integer matrix semigroups. Int. J. Algebra Comput. 01(02), 223–226 (1991)
Ko, S.-K., Potapov, I.: Matrix semigroup freeness problems in SL\((2,\mathbb{Z})\) (2016). CoRR, abs/1610.09834
Kozen, D.: Lower bounds for natural proof systems. In: Proceedings of the 18th Annual Symposium on Foundations of Computer Science, pp. 254–266 (1977)
Lyndon, R.C., Schupp, P.E.: Combinatorial Group Theory. Springer, Heidelberg (1977)
Mackenzie, D.: A New Twist in Knot Theory, vol. 7 (2009)
Mandel, A., Simon, I.: On finite semigroups of matrices. Theor. Comput. Sci. 5(2), 101–111 (1977)
Noll, T.: Musical intervals and special linear transformations. J. Math. Music 1(2), 121–137 (2007)
Polterovich, L., Rudnick, Z.: Stable mixing for cat maps and quasi-morphisms of the modular group. Ergodic Theor. Dyn. Syst. 24, 609–619 (2004)
Potapov, I.: From post systems to the reachability problems for matrix semigroups and multicounter automata. In: Calude, C.S., Calude, E., Dinneen, M.J. (eds.) DLT 2004. LNCS, vol. 3340, pp. 345–356. Springer, Heidelberg (2004). doi:10.1007/978-3-540-30550-7_29
Potapov, I.: Composition problems for braids. In: IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science, vol. 24, pp. 175–187 (2013)
Potapov, I., Semukhin, P.: Vector reachability problem in SL\((2, \mathbb{Z})\). In: 41st International Symposium on Mathematical Foundations of Computer Science, pp. 84:1–84:14 (2016)
Rankin, R.: Modular Forms and Functions. Cambridge University Press, Cambridge (1977)
Shallit, J.: A Second Course in Formal Languages and Automata Theory, 1st edn. Cambridge University Press, New York (2008)
Witten, E.: SL\((2, \mathbb{Z})\) action on three-dimensional conformal field theories with abelian symmetry, vol. 2, pp. 1173–1200 (2005)
Woeginger, G.J., Yu, Z.: On the equal-subset-sum problem. Inf. Process. Lett. 42(6), 299–302 (1992)
Zagier, D.: Elliptic Modular Forms and Their Applications, pp. 1–103 (2008)
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Ko, SK., Potapov, I. (2017). Matrix Semigroup Freeness Problems in SL\((2,\mathbb {Z})\) . In: Steffen, B., Baier, C., van den Brand, M., Eder, J., Hinchey, M., Margaria, T. (eds) SOFSEM 2017: Theory and Practice of Computer Science. SOFSEM 2017. Lecture Notes in Computer Science(), vol 10139. Springer, Cham. https://doi.org/10.1007/978-3-319-51963-0_21
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