Abstract
Green and Ruzsa recently proved that for any s ≥ 2, any small squaring set A in a (multiplicative) abelian group, i.e., |A·A| < K|A|, has a Freiman smodel: it means that there exists a group G and a Freiman s-isomorphism from A into G such that |G| < f (s,K)|A|.
In an unpublished note, Green proved that such a result does not necessarily hold in nonabelian groups if s ≥ 64. The aim of this paper is improve Green’s result by showing that it remains true under the weaker assumption s ≥ 6.
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References
N. Alon and J. Spencer The Probabilistic Method, 2nd edition, Wiley Interscience, New York, 2000.
B. Green, A note on Freiman models, Unpublished note, (2008) available on http://www.dpmms.cam.ac.uk/~bjg23/notes.html
B. Green and I. Z. Ruzsa, Freiman’s theorem in an arbitrary abelian group, Journal of the London Mathematical Society. Second Series 75 (2007), 163–175.
I. Z. Ruzsa, Sumsets and structure, in Combinatorial Number Theory and Additive Group Theory, Advanced Courses in Mathematics, CRM Barcelona, Birkhäuser Verlag, Basel, 2009, pp. 87–210.
W. R. Scott, Group Theory, Second edn., Dover Publications, New York, 1987, xiv+479 pp.
T. Tao and V. H. Vu, Additive Combinatorics, Cambridge Studies in Advanced Mathematics 105, Cambridge University Press, Cambridge, 2006, xviii+512 pp.
L. A. Vinh, Szemerédi-Trotter type theorem and sum-product estimate in finite fields, European Journal of Combinatorics, to appear.
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Research is partially supported by OTKA grants K 67676, K 81658 and Balaton Program Project.
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Hegyvári, N., Hennecart, F. A note on Freiman models in Heisenberg groups. Isr. J. Math. 189, 397–411 (2012). https://doi.org/10.1007/s11856-011-0175-5
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DOI: https://doi.org/10.1007/s11856-011-0175-5