We prove that among all the convex bounded domains in having an assigned Fraenkel asymmetry index, there exists only one convex set (up to a similarity) which minimizes the isoperimetric deficit. We show how to construct this set. The result can be read as a sharp improvement of the isoperimetric inequality for convex planar domains.
@article{BUMI_2008_9_1_3_573_0,
author = {Carlo Nitsch},
title = {The Quantitative Isoperimetric Inequality for Planar Convex Domains},
journal = {Bollettino dell'Unione Matematica Italiana},
volume = {1},
year = {2008},
pages = {573-589},
zbl = {1190.26025},
mrnumber = {2455332},
language = {en},
url = {http://dml.mathdoc.fr/item/BUMI_2008_9_1_3_573_0}
}
Nitsch, Carlo. The Quantitative Isoperimetric Inequality for Planar Convex Domains. Bollettino dell'Unione Matematica Italiana, Tome 1 (2008) pp. 573-589. http://gdmltest.u-ga.fr/item/BUMI_2008_9_1_3_573_0/
[1] - - , The sharp isoperimetric inequality in the plane, preprint (2008). | MR 2735080 | Zbl 1219.52006
[2] - - , On optimization problems with prescribed rearrangements, Nonlinear Anal., Theory Methods Appl. 13 (1989), no. 2, 185-220. | MR 979040 | Zbl 0678.49003
[3] , Isoperimetric inequalities and applications, Monographs and Studies in Mathematics, 7. Boston, London, Melbourne: Pitman Advanced Publishing Program. X, 228 p., 1980. | MR 572958 | Zbl 0436.35063
[4] , Kreis und Kugel, Leipzig: Veit u. Co., X u. 169 S. gr. 8°, 1916. | MR 77958
[5] , Über eine Verscharfung der isoperimetrischen Ungleichheit des Kreises in der Ebene und auf der Kugeloberfläche nebst einer Anwendung auf eine Minkowskische Ungleichheit für konvexe Körper, Math. Ann.84 (1921), no. 3-4, 216-227. | MR 1512031 | Zbl 48.0591.03
[6] , Über das isoperimetrische Defizit ebener Figuren, Math. Ann.91 (1924), no. 3-4, 252-268. | MR 1512192
[7] , Les problèmes des isopérimètres et des isépiphanes, 175 p. Paris, Gauthier-Villars (Collection de monographies sur la théorie des fonctions), 1929.
[8] - , Geometric inequalities. Transl. from the Russian by A. B. Sossinsky. Transl. from the Russian by A.B. Sossinsky, Grundlehren der Mathematischen Wissenschaften, 285. Berlin etc.: Springer-Verlag. XIV, 331 p., 1988. | MR 936419 | Zbl 0633.53002
[9] , Isoperimetric inequalities. Differential geometric and analytic perspectives, Cambridge Tracts in Mathematics. 145. Cambridge: Cambridge University Press. xii, 268 p. , 2001. | MR 1849187 | Zbl 0988.51019
[10] , Sulla proprieta isoperimentrica dell'ipersfera, nella classe degli insiemi aventi frontiera orientata di misura finita, Atti Accad. Naz. Lincei, Mem., Cl. Sci. Fis. Mat. Nat., Sez. I, VIII. Ser. 5 (1958), 33-44. | MR 98331 | Zbl 0116.07901
[11] - - , A quantitative version of the isoperimetric inequality: the anisotropic case, Ann. Sc. Norm. Super. Pisa, Cl. Sci. (5) 4 (2005), no. 4, 691-638. | MR 2207737 | Zbl 1170.52300
[12] - - , A mass transportation approach to quantitative isoperimetric inequalities, preprint (2007). | MR 2672283 | Zbl 1196.49033
[13] , Stability in the isoperimetric problem for convex or nearly spherical domains in ., Trans. Am. Math. Soc.314 (1989), no. 2, 619-638. | MR 942426 | Zbl 0679.52007
[14] - - , The sharp quantitative isoperimetric inequality, to appear on Ann. of Math. | MR 2456887 | Zbl 1187.52009
[15] , The classical isoperimetric theorem, Rend. Acc. Sc. fis. mat. Napoli LXXI, (2004), 63-107. | MR 2147710 | Zbl 1096.49024
[16] , A quantitative isoperimetric inequality in n-dimensional space, J. Reine Angew. Math.428 (1992), 161-175. | MR 1166511 | Zbl 0746.52012
[17] - , A problem in the theory of subordination, J. Anal. Math. 60 (1993), 99-111. | MR 1253231 | Zbl 0851.42008
[18] - - , Inequalities. 2nd ed., 1st. paperback ed., Cambridge Mathematical Library. Cambridge (UK) etc.: Cambridge University Press. xii, 324 p., 1988. | MR 944909
[19] , On the isoperimetric problem. (Sur le problème des isopérimètres.), C. R. 132 (1901), 401-403. | Zbl 32.0386.01
[20] , Rearrangements and convexity of level sets in PDE, Lecture Notes in Mathematics.1150. Berlin etc.: Springer-Verlag. V, 136 p. DM 21.50, 1985. | MR 810619 | Zbl 0593.35002
[21] , Lecons sur les séries trigonométriques professées au Collège de France, Paris: Gauthier-Villars. 125 S. 8 , 1906. | MR 389527 | Zbl 37.0281.01
[22] , The isoperimetric inequality, Bull. Am. Math. Soc.84 (1978), 1182- 1238. | MR 500557 | Zbl 0411.52006
[23] , Bonnesen-style isoperimetric inequalities., Am. Math. Mon.86 (1979), 1-29. | MR 519520 | Zbl 0404.52012
[24] - , Area minimizing sets subject to a volume constraint in a convex set, J. Geom. Anal. 7 (1997), no. 4, 653-677. | MR 1669207 | Zbl 0940.49025
[25] , Elliptic equations and rearrangements, Ann. Sc. Norm. Super. Pisa, Cl. Sci., IV. Ser. 3 (1976), 697-718. | MR 601601 | Zbl 0341.35031
[26] , Linear elliptic P.D.E.'s: Level sets. Rearrangements and a priori estimates of solutions, Boll. Unione Mat. Ital., VI. Ser., B 4 (1985), 917-949. | MR 831299 | Zbl 0602.35025
[27] , The standard isoperimetric theorem., (ed.) et al., Hand-book of convex geometry. Volume A. Amsterdam: North-Holland. (1993), 73-123. | MR 1242977 | Zbl 0799.51015