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Generalised Cantor sets and the dimension of products

Published online by Cambridge University Press:  30 October 2015

ERIC J. OLSON
Affiliation:
Mathematics and Statistics, University of Nevada, Reno, NV, 89507, U.S.A. e-mail: [email protected]
JAMES C. ROBINSON
Affiliation:
Mathematics Institute, University of Warwick, Coventry, CV47AL. e-mail: [email protected]
NICHOLAS SHARPLES
Affiliation:
Department of Mathematics, Imperial College London, London, UK, SW72AZ e-mail: [email protected]

Abstract

In this paper we consider the relationship between the Assouad and box-counting dimension and how both behave under the operation of taking products. We introduce the notion of ‘equi-homogeneity’ of a set, which requires a uniformity in the cardinality of local covers at all length-scales and at all points, and we show that a large class of homogeneous Moran sets have this property. We prove that the Assouad and box-counting dimensions coincide for sets that have equal upper and lower box-counting dimensions provided that the set ‘attains’ these dimensions (analogous to ‘s-sets’ when considering the Hausdorff dimension), and the set is equi-homogeneous. Using this fact we show that for any α ∈ (0, 1) and any β, γ ∈ (0, 1) such that β + γ ⩾ 1 we can construct two generalised Cantor sets C and D such that dimBC = αβ, dimBD = α γ, and dimAC = dimAD = dimA (C × D) = dimB (C × D) = α.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2015 

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References

REFERENCES

[1]Assouad, P.Étude d'une dimension métrique liéea la possibilité de plongements dans $\mathbb{R}$n. C.R. Acad. Sci. Paris Sér. A-B 288 (1979), A731A734.Google Scholar
[2]Besicovitch, A.S. and Moran, P.A.P.The measure of product and cylinder sets. J. Lond. Math. Soc. 20 (1945), 110120.Google Scholar
[3]Bouligand, G.Ensembles impropres et nombre dimensionnels. Bull. Sci. Math. 52 (1928), 320344.Google Scholar
[4]David, G. and Semmes, S.Fractured Fractals and Broken Dreams: Self-Similar Geometry Through Metric and Measure (Oxford University Press, 1997)CrossRefGoogle Scholar
[5]Falconer, K.J.Fractal Geometry: Mathematical Foundations and Applications (3rd edition) (John Wiley and Sons, England, 2014).Google Scholar
[6]Feng, D., Wen, Z. and Wu, J.Some dimensional results for homogeneous Moran sets Sci. China Math. 40 (1997), no. 5, 475482.CrossRefGoogle Scholar
[7]Fraser, J.Assouad type dimensions and homogeneity of fractals. Trans. Amer. Math. Soc. 366 (2014), 66876733.CrossRefGoogle Scholar
[8]Fraser, J., Miao, J.-J. and Troscheit, S. The Assouad dimension of randomly generated fractals. ArXiv Preprint arXiv:1410.6949v2Google Scholar
[9]Henderson, A.M., Olson, E.J., Robinson, J. C. and Sharples, N. Equi-homogeneity, Assouad dimension and non-autonomous dynamics. (Submitted).Google Scholar
[10]Howroyd, J.D.On dimension and on the existence of sets of finite positive Hausdorff measure. Proc. Lond. Math. Soc. s3–70 (1995), no. 3, 581604.CrossRefGoogle Scholar
[11]Larman, D.G.A new theory of dimension. Proc. Lond. Math. Soc. s3–17 (1967), no. 1, 178192.CrossRefGoogle Scholar
[12]Li, W.-W., Li, W.-X., Miao, J.-J. and Xi, L.-F. Assouad dimensions of Moran sets and Cantor-like sets. ArXiv Preprint arXiv:1404.4409v3Google Scholar
[13], F., Lou, M.-L., Wen, Z.-Y. and Xi, L.-F. Bilipschitz embeddings of homogeneous fractals. ArXiv Preprint arXiv:1402.0080Google Scholar
[14]Luukkainen, J.Assouad dimension: antifractal metrization, porous sets, and homogeneous measures. J. Korean Math. Soc. 35 (1998), no. 1, 2376.Google Scholar
[15]Moran, P.A.P.Additive functions of intervals and Hausdorff measure. Math. Proc. Camb. Phil. Soc. 42 (1946), no. 1, 1523.CrossRefGoogle Scholar
[16]Olson, E.J.Bouligand dimension and almost Lipschitz embeddings. Pacific J. Math. 202 (2002), no. 2, 459474.CrossRefGoogle Scholar
[17]Olson, E.J. and Robinson, J.C. A simple example concerning the upper box-counting dimension of a Cartesian product. Real Anal. Exchange (2014), (to appear).Google Scholar
[18]Robinson, J.C.Infinite-dimensional dynamical systems: an introduction to dissipative parabolic PDEs and the theory of global attractors. Cambridge Texts in Applied Math. (Cambridge University Press, 2001).CrossRefGoogle Scholar
[19]Robinson, J.C.Dimensions, embeddings, and attractors. Cambridge Tracts in Math., no. 186 (Cambridge University Press, 2011).Google Scholar
[20]Robinson, J.C. and Sharples, N.Strict inequality in the box-counting dimension product formulas. Real Anal. Exchange 38 (2013), no. 1, 95119.CrossRefGoogle Scholar
[21]Žubrinić, D.Analysis of Minkowski contents of fractal sets and applications. Real Anal. Exchange 31 (2005/2006) no. 2, 315354.CrossRefGoogle Scholar