Hostname: page-component-76fb5796d-vfjqv Total loading time: 0 Render date: 2024-04-28T15:09:35.002Z Has data issue: false hasContentIssue false

A devil's staircase from rotations and irrationality measures for Liouville numbers

Published online by Cambridge University Press:  01 November 2008

DOYONG KWON*
Affiliation:
Pohang Mathematics Institute, Department of Mathematics, POSTECH, Pohang 790-784, Republic of Korea. e-mail: doyong@postech.ac.kr

Abstract

From Sturmian and Christoffel words we derive a strictly increasing function Δ:[0,∞) → . This function is continuous at every irrational point, while at rational points, left-continuous but not right-continuous. Moreover, it assumes algebraic integers at rationals, and transcendental numbers at irrationals. We also see that the differentiation of Δ distinguishes some irrationality measures of real numbers.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Adamczewski, B. and Bugeaud, Y.On the complexity of algebraic numbers II. Continued fractions. Acta Math. 195 (2005), 120.Google Scholar
[2]Adamczewski, B. and Bugeaud, Y.On the complexity of algebraic numbers I. Expansions in integer bases. Ann. of Math. (2) 165 (2007), 547565.CrossRefGoogle Scholar
[3]Adamczewski, B. and Bugeaud, Y.Dynamics for β-shifts and Diophantine approximation. Ergodic Theory Dynam. Systems 27 (2007), 16951711.Google Scholar
[4]Adamczewski, B. and Cassaigne, J.Diophantine properties of real numbers generated by finite automata. Compos. Math. 142 (2006), 13511372.Google Scholar
[5]Allouche, J.-P., Davison, J. L., Queffélec, M. and Zamboni, L. Q.Transcendence of Sturmian or morphic continued fractions. J. Number Theory 91 (2001), 3966.CrossRefGoogle Scholar
[6]Blanchard, F.β-expansions and symbolic dynamics. Theoret. Comput. Sci. 65 (1989), 131141.Google Scholar
[7]Bullett, S. and Sentenac, P.Ordered orbits of the shift, square roots, and the devil's staircase. Math. Proc. Camb. Phil. Soc. 115 (1994), 451481.CrossRefGoogle Scholar
[8]Chi, D. P. and Kwon, D. Y.Sturmian words, β-shifts, and transcendence. Theoret. Comput. Sci. 321 (2004), 395404.Google Scholar
[9]Fel'dman, N. I. and Nesterenko, Y. V.Number Theory IV: Transcendental Numbers. (Springer-Verlag, 1998).Google Scholar
[10]Ferenczi, S. and Mauduit, C.Transcendence of numbers with a low complexity expansion. J. Number Theory 67 (1997), 146161.CrossRefGoogle Scholar
[11]Hardy, G. H. and Wright, E. M.An Introduction to the Theory of Numbers. (Oxford University Press, 1979).Google Scholar
[12]Khinchin, A. Ya.Continued Fractions. (The University of Chicago Press, 1964).Google Scholar
[13]Kwon, D. Y.Beta-numbers whose conjugates lie near the unit circle. Acta Arith. 127 (2007), 3347.CrossRefGoogle Scholar
[14]Lothaire, M.Algebraic Combinatorics on Words. (Cambridge University Press, 2002).CrossRefGoogle Scholar
[15]Parry, W. On the β-expansion of real numbers. Acta Math. Acad. Sci. Hungar. 11 (1960), 401416.CrossRefGoogle Scholar
[16]Rockett, A. M. and Szüsz, P.Continued Fractions (World Scientific, 1992).Google Scholar
[17]Roth, K. F.Rational approximations to algebraic numbers. Mathematika 2 (1955), 120; corrigendum 168.CrossRefGoogle Scholar
[18]Sondow, J. An irrationality measure for Liouville numbers and conditional measures for Euler's constant. 23rd Journées Arithmétiques, Graz, Austria (2003). See also http://arxiv.org/abs/math.NT/0406300.Google Scholar
[19]Verger-Gaugry, J.-L.On gaps in Rényi β-expansions of unity for β1 an algebraic number. Ann. Inst. Fourier (Grenoble) 56 (2006), 25652579.Google Scholar