Preperiodic points for rational functions defined over a global field in terms of good reduction

Let $phi$ be an endomorphism of the projective line defined over a global field $K.$ We prove a bound for the cardinality of the set of $K$–rational preperiodic points for φ in terms of the number of places of bad reduction. The result is completely new in the function field case and is an improvement of the number field case.

[1]  Jan-Hendrik Evertse,et al.  On equations inS-units and the Thue-Mahler equation , 1984 .

[2]  Robert L. Benedetto,et al.  Preperiodic points of polynomials over global fields , 2005, math/0506480.

[3]  Patrick Morton,et al.  Arithmetic properties of periodic points of quadratic maps, II , 1992 .

[4]  J. Evertse,et al.  LINEAR EQUATIONS WITH UNKNOWNS FROM A MULTIPLICATIVE GROUP IN A FUNCTION FIELD , 2004, math/0401231.

[5]  T. Apostol Introduction to analytic number theory , 1976 .

[6]  Barry Mazur,et al.  On Periodic Points , 1965 .

[8]  Laura Paladino On counterexamples to local-global divisibility in commutative algebraic groups , 2011 .

[9]  Joseph H. Silverman,et al.  Diophantine Geometry: An Introduction , 2000, The Mathematical Gazette.

[10]  Pierre Parent,et al.  Bornes effectives pour la torsion des courbes elliptiques sur les corps de nombres , 1996, alg-geom/9604003.

[11]  Cycles for rational maps of good reduction outside a prescribed set , 2005, math/0504533.

[12]  J. Canci,et al.  On some notions of good reduction for endomorphisms of the projective line , 2011, 1103.3853.

[13]  U. Zannier Lecture Notes on Diophantine Analysis , 2014 .

[14]  W. Narkiewicz,et al.  Polynomial cycles in algebraic number fields , 1989 .

[16]  R. Benedetto A criterion for potentially good reduction in nonarchimedean dynamics , 2013, 1311.6695.

[17]  Joseph H. Silverman,et al.  Periodic points, multiplicities, and dynamical units. , 1995 .

[18]  Joseph H. Silverman,et al.  Rational periodic points of rational functions , 1994 .

[19]  Henning Stichtenoth,et al.  Algebraic function fields and codes , 1993, Universitext.

[20]  Evelina Viada,et al.  On local-global divisibility by $p^2$ in elliptic curves , 2011, 1103.4963.

[21]  Patrick Ingram,et al.  On Poonen's Conjecture Concerning Rational Preperiodic Points of Quadratic Maps , 2009, 0909.5050.

[22]  Loïc Merel,et al.  Bornes pour la torsion des courbes elliptiques sur les corps de nombres , 1996 .

[23]  J. Silverman The Arithmetic of Dynamical Systems , 2007 .

[24]  Finite orbits for rational functions , 2005, math/0512338.

[25]  F. Beukers,et al.  The equation x+y=1 in finitely generated groups , 1996 .

[26]  U. Zannier,et al.  Local-global divisibility of rational points in some commutative algebraic groups , 2001 .

[27]  Michael Rosen,et al.  Number Theory in Function Fields , 2002 .

[28]  J. Voloch The Equation ax+ by=1 in Characteristic p , 1998 .

[29]  M. Stoll Rational 6-Cycles Under Iteration of Quadratic Polynomials , 2008, LMS J. Comput. Math..

[30]  Bjorn Poonen,et al.  Cycles of quadratic polynomials and rational points on a genus-$2$ curve , 1995 .

[31]  J. Voloch The Equationax+by=1 in Characteristicp , 1998 .