The Ramanujan Journal

, Volume 22, Issue 1, pp 33–54 | Cite as

On sums and products in ℂ[x]

Article

Abstract

We prove that there exists an absolute constant c>0 such that if A is a set of n monic polynomials, and if the product set A.A has at most n 1+c elements, then |A+A|≫n2. This can be thought of as step towards proving the Erdős–Szemerédi sum-product conjecture for polynomial rings. We also show that under a suitable generalization of Fermat’s Last Theorem, the same result holds for the integers. The methods we use to prove are a mixture of algebraic (e.g. Mason’s theorem) and combinatorial (e.g. the Ruzsa–Plunnecke inequality) techniques.

Keywords

Sum-product Mason’s theorem ABC theorem Erdős–Szemerédi conjecture Fermat’s last theorem 

Mathematics Subject Classification (2000)

11B30 11C08 

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of MathematicsGeorgia Institute of TechnologyAtlantaUSA
  2. 2.Hill Center for Mathematical SciencesRutgers UniversityPiscatawayUSA

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