A Schur ring (an S-ring) is said to be separable if each of its algebraic isomorphisms is induced by an isomorphism. Let C n be the cyclic group of order n. It is proved that all S-rings over groups \( D={C}_p\times {C}_{p^k} \), where p ∈ {2, 3} and k ≥ 1, are separable with respect to a class of S-rings over Abelian groups. From this statement, we deduce that a given Cayley graph over D and a given Cayley graph over an arbitrary Abelian group can be checked for isomorphism in polynomial time with respect to |D|.
Similar content being viewed by others
References
I. Schur, “Zur Theorie der einfach transitiven Permutationsgruppen,” Sitzungsber. Preuß. Akad. Wiss., Phys.-Math. Kl., 18, No. 20, 598-623 (1933).
H. Wielandt, Finite Permutation Groups, Academic Press, New York (1964).
S. Evdokimov and I. Ponomarenko, “On the separability problem for circulant S-rings,” Alg. An., 28, No. 1, 32-51 (2016).
S. A. Evdokimov and I. N. Ponomarenko, “On a family of Schur rings over a finite cyclic group,” Alg. An., 13, No. 3, 139-154 (2001).
J. Golfand and M. Klin, “Amorphic cellular rings I,” in Investigations in Algebraic Theory of Combinatorial Objects, VNIISI, Moscow, 32-38 (1985).
M. Muzychuk and I. Ponomarenko, “On Schur 2-groups,” Zap. POMI, 435, 113-162 (2015).
G. Ryabov, “On Schur p-groups of odd order,” J. Alg. Appl., 16, No. 3 (2017); article ID 1750045.
S. Evdokimov and I. Ponomarenko, “Permutation group approach to association schemes,” Eur. J. Comb., 30, No. 6, 1456-1476 (2009).
On Construction and Identification of Graphs, B. Weisfeiler (ed.), Lect. Notes Math., 558, Springer-Verlag, Berlin (1976).
B. Weisfeiler and A. Leman, “Reduction of a graph to a canonical form and an algebra which appears in the process,” NTI, 2, No. 9, 12-16 (1968).
S. A. Evdokimov and I. N. Ponomarenko, “Recognizing and isomorphism testing circulant graphs in polynomial time,” Alg. An., 15, No. 6, 1-34 (2003).
M. Muzychuk, “A solution of the isomorphism problem for circulant graphs,” Proc. London Math. Soc., III. Ser., 88, No. 1, 1-41 (2004).
M. Muzychuk and I. Ponomarenko, “Schur rings,” Eur. J. Comb., 30, No. 6, 1526-1539 (2009).
S. Evdokimov and I. Ponomarenko, “Coset closure of a circulant S-ring and schurity problem,” J. Alg. Appl., 15, No. 4 (2016); article ID 1650068.
S. A. Evdokimov, “Schurity and separability of association schemes,” Thesis, SPbU, St. Petersburg (2004).
M. Muzychuk and I. Ponomarenko, “On quasi-thin association schemes,” J. Alg., 351, No. 1, 467-489 (2012).
S. A. Evdokimov and I. N. Ponomarenko, “Schurity of S-rings over a cyclic group and generalized wreath product of permutation groups,” Alg. An., 24, No. 3, 84-127 (2012).
S. A. Evdokimov and I. N. Ponomarenko, “Characterization of cyclotomic schemes and normal Schur rings over a cyclic group,” Alg. An., 14, No. 2, 11-55 (2002).
M. Klin, C. Pech, and S. Reichard, COCO2P—A GAP Package, Vers. 0.14, 07.02.2015; http://www.math.tu-dresden.de/∼pech/COCO2P.
Author information
Authors and Affiliations
Corresponding author
Additional information
Supported by RFBR, project No. 17-51-53007.
Translated from Algebra i Logika, Vol. 57, No. 1, pp. 73-101, January-February, 2018.
Rights and permissions
About this article
Cite this article
Ryabov, G.K. Separability of Schur Rings over Abelian p-Groups. Algebra Logic 57, 49–68 (2018). https://doi.org/10.1007/s10469-018-9478-5
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10469-018-9478-5