Abstract
We geometrically describe families of non-convex plane and spatial domains in which the basic Hardy inequality is valid with the constant 1/4. In our constructions we use some new constants depending on the dimension; we determine them as roots of Lamb-type equations. We also use the constant defined by E. B. Davies.
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References
E. B. Davies, “The Hardy Constant,” Quart. J. Math. Oxford (2) 46(4), 417–431 (1995).
T. Matskewich and P. E. Sobolevskii, “The Best Possible Constant in a Generalized Hardy’s Inequality for Convex Domains in Rn,” Nonlinear Anal. 28(9), 1601–1610 (1997).
H. Brezis and M. Marcus, “Hardy’s Inequalities Revisited,” Dedicated to Ennio De Giorgi. Ann. Scuola Norm. Sup. Pisa Cl. Sci. (4), 25(1–2), 217–237 (1997–1998).
M. Marcus, V. J. Mitzel, and Y. Pinchover, “On the BestConstant for Hardy’s Inequality inRn,” Trans. Amer. Math. Soc. 350(8), 3237–3250 (1998).
G. Barbatis, S. Filippas, and A. Tertikas, “A Unified Approach to Improved L p Hardy Inequalities with Best Constants,” Trans. Amer. Math. Soc. 356(6), 2169–2196 (2004).
D. H. Armitage and U. Kuran, “The Convexity and the Superharmonicity of the Signed Distance Function,” Proc. Amer. Math. Soc. 93(4), 598–600 (1985).
F. G. Avkhadiev and A. Laptev, “Hardy Inequalities for Nonconvex Domains,” in Around Research of Vladimir Maz’ya. I. Int. Math. Ser. (Springer, N. Y., 2010), Vol. 11, pp. 1–12.
F. G. Avkhadiev, “Hardy Type Inequalities in Higher Dimensions with Explicit Estimate of Constants,” Lobachevskii J. Math. 21, 3–31 (2006).
F. G. Avkhadiev, “Hardy-Type Inequalities on Planar and Spatial Open Sets,” TrudyMatem. Inst. 255, 2–12 (2006).
S. Fillipas, V. Maz’ya, and A. Tertikas, “On a Question of Brezis and Marcus,” Calc. Var. Partial Diff. Equat. 25(1), 491–501 (2005).
F. G. Avkhadiev and K.-J. Wirths, “Unified Poincaré and Hardy Inequalitieswith Sharp Constants for Convex Domains,” Z. Angew. Math. Mech. 87(8–9), 632–642 (2007).
F. G. Avkhadiev and K.-J. Wirths, “Weighted Hardy Inequalities with Sharp Constants,” Lobachevskii J. Math. 31(1), 1–7 (2010).
F. G. Avkhadiev and K.-J. Wirths, “Sharp Hardy-Type Inequalities with Lamb’s Constants,” Bull. Belg. Math. Soc. Simon Stevin 18(4), 723–736 (2011).
F. G. Avkhadiev, R. G. Nasibullin, and I. K. Shafigullin, “Hardy-Type Inequalities with Power and Logarithmic Weights in Domains of the Euclidean Space,” Izv. Vyssh. Uchebn. Zaved. Mat., No. 9, 90–94 (2011) [Russian Mathematics (Iz. VUZ) 55 (9), 76–79 (2011).
H. Lamb, “Note on the Induction of Electric Currents in a Cylinder Placed Across the Lines of Magnetic Force,” Proc. London Math. Soc. XV, 270–274 (1884).
J. E. Littlewood, Lecture on the Theory of Functions (Oxford University Press, Oxford, 1944).
F. G. Avkhadiev and K.-J. Wirths, Schwarz-Pick Type Inequalities (Birkhäuser Verlag, Basel, 2009).
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Original Russian Text © F.G. Avkhadiev, 2013, published in Izvestiya Vysshikh Uchebnykh Zavedenii. Matematika, 2013, No. 9, pp. 59–63.
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Avkhadiev, F.G. Families of domains with best possible hardy constant. Russ Math. 57, 49–52 (2013). https://doi.org/10.3103/S1066369X13090077
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DOI: https://doi.org/10.3103/S1066369X13090077