Disuguaglianze di Harnack per operatori di evoluzione ipoellittici: aspetti geometrici ed applicazioni

Autori

  • Sergio Polidoro Università di Modena

DOI:

https://doi.org/10.6092/issn.2240-2829/3415

Parole chiave:

hypoelliptic equations, Harnack inequality, potential theory, Malliavin calculus

Abstract

Consideriamo Equazioni alle Derivate Parziali lineari del secondo ordine in forma di "somma di quadrati di campi vettoriali di Hörmander piu un termine di drift" in un dominio assegnato. Dimostriamo che una disuguaglianza di Harnack vale in ogni sottoinsieme compatto dell'insieme raggiungibile denito in termini dei compi vettoiali che definiscono l'Equazione alle Derivate Parziali considerata. Applichiamo quindi le disuguaglianze di Harnack per dimostrare stime asintotiche dal basso per la densità congiunta di un'ampia classe di processi stocastici. Analoghe stime dall'alto sono dimostrate per mezzo del Calcolo di Malliavin.

Riferimenti bibliografici

D. G. Aronson, Bounds for the fundamental solution of a parabolic equation, Bull. Amer. Math. Soc., 73 (1967), pp. 890–896.

H. Bauer, Harmonische R¨aume und ihre Potentialtheorie, Ausarbeitung einer im Sommersemester 1965 an der Universit¨at Hamburg gehaltenen Vorlesung. Lecture Notes in Mathematics, No. 22, Springer-Verlag, Berlin, 1966.

G. Ben Arous, R. L´eandre, D´ecroissance exponentielle du noyau de la chaleur sur la diagonale.

II, Probab. Theory Related Fields, 90 (1991), pp. 377–402.

A. Bonfiglioli, E. Lanconelli, On left invariant H¨ormander operators in RN. Applications to Kolmogorov-Fokker-Planck equations, Proceeding of the Fifth International Conference on Differential and Functional Differential Equations, Moscow, August 17-24, 2008 (to appear).

A. Bonfiglioli, E. Lanconelli, F. Uguzzoni, Stratified Lie groups and potential theory for their sub-Laplacians, Springer Monographs in Mathematics, Springer, Berlin, 2007.

A. N. Borodin, P. Salminen, Handbook of Brownian motion—facts and formulae, Probability and its Applications, Birkh¨auser Verlag, Basel, second ed., 2002.

U. Boscain, S. Polidoro, Gaussian estimates for hypoelliptic operators via optimal control, Atti Accad. Naz. Lincei Cl. Sci. Fis. Mat. Natur. Rend. Lincei (9) Mat. Appl., 18 (2007), pp. 333–342.

C. Cinti, S. Menozzi, S. Polidoro, Two-sided bounds for degenerate processes with densities supported in subsets of Rn, (preprint), (2012).

C. Cinti, K. Nystr¨om, S. Polidoro, A note on Harnack inequalities and propagation sets for a class of hypoelliptic operators, preprint, (2010).

C. Constantinescu, A. Cornea, Potential theory on harmonic spaces, Springer-Verlag, New York, 1972. With a preface by H. Bauer, Die Grundlehren der mathematischen Wissenschaften, Band 158.

M. Di Francesco, S. Polidoro, Schauder estimates, Harnack inequality and Gaussian lower bound for Kolmogorov type operators in non-divergence form, Advances in Differential Equations, 11 (2006), pp. 1261–1320.

N. Garofalo, E. Lanconelli, Level sets of the fundamental solution and Harnack inequality for degenerate equations of Kolmogorov type, Trans. Amer. Math. Soc., 321 (1990), pp. 775–792.

M. Kac, On distributions of certain Wiener functionals, Trans. Amer. Math. Soc., 65 (1949), pp. 1–13.

L. P. Kupcov, Harnack’s inequality for generalized solutions of second order degenerate elliptic equations, Differencial′nye Uravnenija, 4 (1968), pp. 110–122.

, The fundamental solutions of a certain class of elliptic-parabolic second order equations, Differencial′nye Uravnenija, 8 (1972), pp. 1649–1660, 1716.

, The mean value property and the maximum principle for second order parabolic equations, Dokl. Akad. Nauk SSSR, 242 (1978), pp. 529–532.

, On parabolic means, Dokl. Akad. Nauk SSSR, 252 (1980), pp. 296–301.

E. Lanconelli, S. Polidoro, On a class of hypoelliptic evolution operators, Rend. Sem. Mat. Univ. Politec. Torino, 52 (1994), pp. 29–63. Partial differential equations, II (Turin, 1993).

E. B. Lee, L. Markus, Foundations of optimal control theory, Robert E. Krieger Publishing Co. Inc., Melbourne, FL, second ed., 1986.

S. Polidoro, A global lower bound for the fundamental solution of Kolmogorov-Fokker-Planck equations, Arch. Rational Mech. Anal., 137 (1997), pp. 321–340.

N. Smirnov, Sur la distribution de omega^2 (criterium de M. von Mises), C. R. Acad. Sci. Paris, 202 (1936), pp. 449–452.

L. Tolmatz, Asymptotics of the distribution of the integral of the absolute value of the Brownian bridge for large arguments, Ann. Probab., 28 (2000), pp. 132–139.

N. T. Varopoulos, L. Saloff-Coste, T. Coulhon, Analysis and geometry on groups, vol. 100 of Cambridge Tracts in Mathematics, Cambridge University Press, Cambridge, 1992.

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Pubblicato

2012-12-30

Come citare

Polidoro, S. (2012). Disuguaglianze di Harnack per operatori di evoluzione ipoellittici: aspetti geometrici ed applicazioni. Bruno Pini Mathematical Analysis Seminar, 3(1), 1–13. https://doi.org/10.6092/issn.2240-2829/3415

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