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LINEAR FORMS AND QUADRATIC UNIFORMITY FOR FUNCTIONS ON 𝔽np

Published online by Cambridge University Press:  07 March 2011

W. T. Gowers
Affiliation:
Department of Pure Mathematics and Mathematical Statistics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WB, U.K. (email: [email protected])
J. Wolf
Affiliation:
Department of Mathematics, Rutgers The State University of New Jersey, 110 Frelinghuysen Rd., Piscataway, NJ 08854, U.S.A. (email: [email protected])
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Abstract

We give improved bounds for our theorem in [W. T. Gowers and J. Wolf, The true complexity of a system of linear equations. Proc. London Math. Soc. (3) 100 (2010), 155–176], which shows that a system of linear forms on 𝔽np with squares that are linearly independent has the expected number of solutions in any linearly uniform subset of 𝔽np. While in [W. T. Gowers and J. Wolf, The true complexity of a system of linear equations. Proc. London Math. Soc. (3) 100 (2010), 155–176] the dependence between the uniformity of the set and the resulting error in the average over the linear system was of tower type, we now obtain a doubly exponential relation between the two parameters. Instead of the structure theorem for bounded functions due to Green and Tao [An inverse theorem for the Gowers U3(G) norm. Proc. Edinb. Math. Soc. (2) 51 (2008), 73–153], we use the Hahn–Banach theorem to decompose the function into a quadratically structured plus a quadratically uniform part. This new decomposition makes more efficient use of the U3 inverse theorem [B. J. Green and T. Tao, An inverse theorem for the Gowers U3(G) norm. Proc. Edinb. Math. Soc. (2) 51 (2008), 73–153].

Type
Research Article
Copyright
Copyright Š University College London 2011

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References

[1]Bourgain, J., On triples in arithmetic progression. Geom. Funct. Anal. 9(5) (1999), 968–984.CrossRefGoogle Scholar
[2]Candela, P., A U 3 inverse theorem for the P U 3 norm. Preprint, 2007.Google Scholar
[3]Gowers, W. T., Decompositions, approximate structure, transference, and the Hahn–Banach theorem. Bull. London Math. Soc. 42(4) (2010), 573–606.Google Scholar
[4]Gowers, W. T. and Wolf, J., Linear forms and higher-degree uniformity for functions on 𝔽np. Geom. Funct. Anal. (to appear).Google Scholar
[5]Gowers, W. T. and Wolf, J., Linear forms and quadratic uniformity for functions on ℤN. J. Anal. Math. (to appear).Google Scholar
[6]Gowers, W. T. and Wolf, J., The true complexity of a system of linear equations. Proc. London Math. Soc. (3) 100 (2010), 155–176.Google Scholar
[7]Green, B. J., Finite field models in additive combinatorics. In Surveys in Combinatorics 2005 (London Mathematical Society Lecture Notes 327), Cambridge University Press (2005), 1–27.Google Scholar
[8]Green, B. J. and Tao, T., An inverse theorem for the Gowers U 3(G) norm. Proc. Edinb. Math. Soc. (2) 51 (2008), 73–153.CrossRefGoogle Scholar
[9]Green, B. J. and Tao, T., The primes contain arbitrarily long arithmetic progressions. Ann. of Math. (2) 167 (2008), 481–547.Google Scholar
[10]Green, B. J. and Tao, T., New bounds for Szemerédi’s theorem, I: progressions of length 4 in finite field geometries. Proc. London Math. Soc. (3) 98 (2009), 365–392.Google Scholar
[11]Green, B. J. and Tao, T., An equivalence between inverse sumset theorems and inverse conjectures for the U 3 norm. Math. Proc. Cambridge Philos. Soc. 149(1) (2010), 1–19.Google Scholar
[12]Green, B. J. and Tao, T., An arithmetic regularity lemma, an associated counting lemma, and applications. In An Irregular Mind: Szemeredi is 70 (Bolyai Society Mathematical Studies 21), Springer (2010).CrossRefGoogle Scholar
[13]Green, B. J. and Tao, T., Linear equations in primes. Ann. of Math. (2) 171 (2010), 1753–1850.Google Scholar
[14]Samorodnitsky, A., Low-degree tests at large distances. Proceedings of the Thirty-ninth Annual ACM Symposium on Theory of Computing, ACM (New York, NY, 2007), 506–515.Google Scholar
[15]Tao, T. and Vu, V., Additive Combinatorics, Cambridge University Press (Cambridge, 2006).Google Scholar
[16]Wolf, J., A local inverse theorem in 𝔽n2. Preprint, 2009.Google Scholar