Home Galois action on Fuchsian surface groups and their solenoids
Article
Licensed
Unlicensed Requires Authentication

Galois action on Fuchsian surface groups and their solenoids

  • Amir Džambić EMAIL logo and Gabino González-Diez
Published/Copyright: December 12, 2020

Abstract

Let C be a complex algebraic curve uniformized by a Fuchsian group Γ. In the first part of this paper we identify the automorphism group of the solenoid associated with Γ with the Belyaev completion of its commensurator Comm(Γ) and we use this identification to show that the isomorphism class of this completion is an invariant of the natural Galois action of Gal(/) on algebraic curves. In turn, this fact yields a proof of the Galois invariance of the arithmeticity of Γ independent of Kazhhdan’s. In the second part we focus on the case in which Γ is arithmetic. The list of further Galois invariants we find includes: (i) the periods of Comm(Γ), (ii) the solvability of the equations X2+sin22π2k+1 in the invariant quaternion algebra of Γ and (iii) the property of Γ being a congruence subgroup.


Communicated by Jan Bruinier


Funding statement: Second author partially supported by Spanish Government Research Project MTM2016-79497-P.

Acknowledgements

The authors would like to thank Adrián Ubis for the explicit choice of the constant bp in Section 2.1.1, Jürgen Wolfart for many valuable suggestions and Andrei Jaikin-Zapirain for his helpful comments at an early stage of this paper. Finally, the authors would like to thank the referee for his/her careful reading of the paper and the valuable comments and suggestions.

References

[1] W. L. Baily, Jr. and A. Borel, Compactification of arithmetic quotients of bounded symmetric domains, Ann. of Math. (2) 84 (1966), 442–528. 10.2307/1970457Search in Google Scholar

[2] V. V. Belyaev, Locally finite groups with a finite nonseparable subgroup, Sib. Math. J. 34 (1993), no. 2, 218–232. 10.1007/BF00970947Search in Google Scholar

[3] I. Biswas and S. Nag, Limit constructions over Riemann surfaces and their parameter spaces, and the commensurability group actions, Selecta Math. (N. S.) 6 (2000), no. 2, 185–224. 10.1007/PL00001388Search in Google Scholar

[4] A. Borel, Introduction aux groupes arithmétiques, Hermann, Paris, 1969. Search in Google Scholar

[5] F. Catanese, Kodaira fibrations and beyond: methods for moduli theory, Jpn. J. Math. 12 (2017), no. 2, 91–174. 10.1007/s11537-017-1569-xSearch in Google Scholar

[6] T. Chinburg and E. Friedman, An embedding theorem for quaternion algebras, J. Lond. Math. Soc. (2) 60 (1999), no. 1, 33–44. 10.1112/S0024610799007607Search in Google Scholar

[7] K. Doi and H. Naganuma, On the algebraic curves uniformized by arithmetical automorphic functions, Ann. of Math. (2) 86 (1967), 449–460. 10.2307/1970610Search in Google Scholar

[8] N. D. Elkies, Shimura curve computations, Algorithmic Number Theory (Portland 1998), Lecture Notes in Comput. Sci. 1423, Springer, Berlin (1998), 1–47. 10.1007/BFb0054850Search in Google Scholar

[9] N. D. Elkies, The Klein quartic in number theory, The Eightfold Way, Math. Sci. Res. Inst. Publ. 35, Cambridge University, Cambridge (1999), 51–101. Search in Google Scholar

[10] E. Girondo and G. González-Diez, Introduction to Compact Riemann Surfaces and Dessins d’Enfants, London Math. Soc. Stud. Texts 79, Cambridge University, Cambridge, 2012. 10.1017/CBO9781139048910Search in Google Scholar

[11] G. González-Diez, Variations on Belyi’s theorem, Q. J. Math. 57 (2006), no. 3, 339–354. 10.1093/qmath/hai021Search in Google Scholar

[12] G. González-Diez, Galois action on universal covers of Kodaira fibrations, Duke Math. J. 169 (2020), no. 7, 1281–1303. 10.1215/00127094-2019-0078Search in Google Scholar

[13] G. González-Diez and A. Jaikin-Zapirain, The absolute Galois group acts faithfully on regular dessins and on Beauville surfaces, Proc. Lond. Math. Soc. (3) 111 (2015), no. 4, 775–796. 10.1112/plms/pdv041Search in Google Scholar

[14] G. González-Diez, G. A. Jones and D. Torres-Teigell, Arbitrarily large Galois orbits of non-homeomorphic surfaces, Eur. J. Math. 4 (2018), no. 1, 223–241. 10.1007/s40879-017-0203-zSearch in Google Scholar

[15] G. González-Diez and S. Reyes-Carocca, The arithmeticity of a Kodaira fibration is determined by its universal cover, Comment. Math. Helv. 90 (2015), no. 2, 429–434. 10.4171/CMH/359Search in Google Scholar

[16] G. González-Diez and S. Reyes-Carocca, Families of Riemann surfaces, uniformization and arithmeticity, Trans. Amer. Math. Soc. 370 (2018), no. 3, 1529–1549. 10.1090/tran/6988Search in Google Scholar

[17] A. Grothendieck, Esquisse d’un programme, Geometric Galois Actions. 1, London Math. Soc. Lecture Note Ser. 242, Cambridge University, Cambridge (1997), 5–48. 10.1017/CBO9780511758874.003Search in Google Scholar

[18] G. A. Jones and J. Wolfart, Dessins d’Enfants on Riemann surfaces, Springer Monogr. Math., Springer, Cham, 2016. 10.1007/978-3-319-24711-3Search in Google Scholar

[19] S. Kaliszewski, M. B. Landstad and J. Quigg, Hecke C*-algebras, Schlichting completions and Morita equivalence, Proc. Edinb. Math. Soc. (2) 51 (2008), no. 3, 657–695. 10.1017/S0013091506001419Search in Google Scholar

[20] D. Kazhdan, On arithmetic varieties. II, Israel J. Math. 44 (1983), no. 2, 139–159. 10.1007/BF02760617Search in Google Scholar

[21] C. Maclachlan, Introduction to arithmetic Fuchsian groups, Topics on Riemann Surfaces and Fuchsian Groups (Madrid 1998), London Math. Soc. Lecture Note Ser. 287, Cambridge University, Cambridge (2001), 29–41. 10.1017/CBO9780511569272.004Search in Google Scholar

[22] C. Maclachlan, Existence and non-existence of torsion in maximal arithmetic Fuchsian groups, Groups Complex. Cryptol. 1 (2009), no. 2, 287–295. 10.1515/GCC.2009.287Search in Google Scholar

[23] C. Maclachlan and A. W. Reid, The Arithmetic of Hyperbolic 3-Manifolds, Grad. Texts in Math. 219, Springer, New York, 2003. 10.1007/978-1-4757-6720-9Search in Google Scholar

[24] G. A. Margulis, Discrete Subgroups of Semisimple Lie Groups, Ergeb. Math. Grenzgeb. (3) 17, Springer, Berlin, 1991. 10.1007/978-3-642-51445-6Search in Google Scholar

[25] V. Markovic and D. Šarić, Teichmüller mapping class group of the universal hyperbolic solenoid, Trans. Amer. Math. Soc. 358 (2006), no. 6, 2637–2650. 10.1090/S0002-9947-05-03823-7Search in Google Scholar

[26] J. S. Milne and J. Suh, Nonhomeomorphic conjugates of connected Shimura varieties, Amer. J. Math. 132 (2010), no. 3, 731–750. 10.1353/ajm.0.0112Search in Google Scholar

[27] C. Odden, The baseleaf preserving mapping class group of the universal hyperbolic solenoid, Trans. Amer. Math. Soc. 357 (2005), no. 5, 1829–1858. 10.1090/S0002-9947-04-03472-5Search in Google Scholar

[28] R. C. Penner and D. Šarić, Teichmüller theory of the punctured solenoid, Geom. Dedicata 132 (2008), 179–212. 10.1007/s10711-007-9226-9Search in Google Scholar

[29] C. D. Reid and P. R. Wesolek, Homomorphisms into totally disconnected, locally compact groups with dense image, Forum Math. 31 (2019), no. 3, 685–701. 10.1515/forum-2018-0017Search in Google Scholar

[30] L. Ribes and P. Zalesskii, Profinite Groups, Ergeb. Math. Grenzgeb. (3) 40, Springer, Berlin, 2000. 10.1007/978-3-662-04097-3Search in Google Scholar

[31] J.-P. Serre, Exemples de variétés projectives conjuguées non homéomorphes, C. R. Acad. Sci. Paris 258 (1964), 4194–4196. 10.1007/978-3-642-37726-6_63Search in Google Scholar

[32] M. Streit, Field of definition and Galois orbits for the Macbeath–Hurwitz curves, Arch. Math. (Basel) 74 (2000), no. 5, 342–349. 10.1007/s000130050453Search in Google Scholar

[33] D. Sullivan, Linking the universalities of Milnor–Thurston, Feigenbaum and Ahlfors–Bers, Topological Methods in Modern Mathematics (Stony Brook 1991), Publish or Perish, Houston (1993), 543–564. Search in Google Scholar

[34] K. Takeuchi, Arithmetic triangle groups, J. Math. Soc. Japan 29 (1977), no. 1, 91–106. 10.2969/jmsj/02910091Search in Google Scholar

[35] K. Takeuchi, Arithmetic Fuchsian groups with signature (1;e), J. Math. Soc. Japan 35 (1983), 381–404. 10.2969/jmsj/03530381Search in Google Scholar

[36] L. C. Washington, Introduction to Cyclotomic Fields, Grad. Texts in Math. 83, Springer, New York, 1982. 10.1007/978-1-4684-0133-2Search in Google Scholar

[37] J. Wolfart, The “obvious” part of Belyi’s theorem and Riemann surfaces with many automorphisms, Geometric Galois Actions. 1, London Math. Soc. Lecture Note Ser. 242, Cambridge University, Cambridge (1997), 97–112. 10.1017/CBO9780511758874.008Search in Google Scholar

Received: 2020-06-08
Revised: 2020-11-03
Published Online: 2020-12-12
Published in Print: 2021-03-01

© 2020 Walter de Gruyter GmbH, Berlin/Boston

Downloaded on 13.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/forum-2020-0148/html
Scroll to top button