Results 31 to 40 of about 553 (167)
Global hypoellipticity of a Mathieu operator [PDF]
Proceedings of the American Mathematical Society, 1991 The author gives a necessary and sufficient condition for the global hypoellipticity of a Mathieu operator on the d-dimensional torus. As a result he shows the close connection between global hypoellipticity and the positions of zeros and poles of a certain meromorphic function defined by a continued fraction.
openaire +2 more sources
Superparabolic Functions Related to Second Order Hypoelliptic Operators [PDF]
, 1999 In this paper, we consider a wide class of second order hypoelliptic partial differential operators with nonnegative characteristic form.
Pascucci A., Lanconelli E.
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Hypoelliptic estimates for linear transport operators [PDF]
, 2020 We aim at understanding how the non-commutation phenomena between a linear transport operator and a fractional diffusion allow the transport operator to satisfy hypoelliptic estimates on the whole space.
Alphonse, Paul
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On the index of maximally hypoelliptic differential operators [PDF]
, 2022 We give an index formula for the class of all *-maximally hypoelliptic differential operators on any closed manifold with vector bundle coefficients, generalising previous index formulas by Atiyah-Singer and van Erp.
Mohsen, Omar
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AN EQUIVARIANT INDEX THEOREM FOR HYPOELLIPTIC OPERATORS [PDF]
, 2020 . Let M be a foliated manifold and G a discrete group acting on M by diffeomorphisms mapping leaves to leaves. Then G naturally acts by automorphisms on the algebra of Heisenberg pseudodifferential operators on the foliation.
Denis Perrot, Rudy Rodsphon
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Harnack inequalities and Gaussian estimates for a class of hypoelliptic operators [PDF]
, 2005 We announce some results obtained in the recent paper“Harnack inequalities and Gaussian estimates for a class of hypoelliptic operators”, concerning a general class of hypoelliptic evolution operators in R^{N+1}.
Sergio Polidoro, POLIDORO, Sergio
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Liouville-type theorems for some complex hypoelliptic operators [PDF]
, 1985 It is shown that the natural analogue of Liouville's theorem holds for the well-known hypoelliptic operators Lα (for ¦α¦ < n) introduced and studied by Folland and Stein on the Heisenberg group Hn.
Stanton, Nancy K, Korányi, Adam
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Superharmonic functions associated with hypoelliptic non-H"ormander operators [PDF]
, 2020 In this paper, we consider a class of degenerate-elliptic linear operators L in quasi- divergence form and we study the associated cone of superharmonic functions.
E. Battaglia, S. Biagi
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A comparison principle for higher order nonlinear hypoelliptic heat operators on graded Lie groups [PDF]
, 2021 In this paper we present a comparison principle for higher order nonlinear hypoelliptic heat operators on graded Lie groups. Moreover, using the comparison principle we obtain blow-up type results and global in $t$-boundedness of solutions of nonlinear ...
Yessirkegenov, N +3 more
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Hypoelliptic heat kernel inequalities on Lie groups [PDF]
, 2008 This paper discusses the existence of gradient estimates for the heat kernel of a second order hypoelliptic operator on a manifold. For elliptic operators, it is now standard that such estimates (satisfying certain conditions on coefficients) are ...
Melcher, Tai
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