AbstractThe purpose of this paper is to establish the following result. LetL1andL2be subelliptic operators on Rnxand Rmy, respectively. Assume thatλ∈C∞(Rnx) withλ⩾0, assume thatλhas a zero of infinite order at the origin and that all other zeroes ofλare of finite order. Then the operatorL=L1+λL2is hypoelliptic
Let $P(x, D)$ be a partial differential operator with principal symbol $p_m(x, \xi)=q_{m-l}(x, \xi)a...
We study C∞ and analytic hypoellipticity for an invariant class of operators with multiple ch...
We study, for a model class of classical pseudodifferential operators with symplectic characteristic...
Fedii [1] studied hypoellipticity for operators of the form L=D21+ф(x1)2D22 in R2, and proved that L...
We study the hypoellipticity for the operator (1) $P=D_{t}+i\alpha(t)b(t, X, D_{x}) $ in $\mathrm{R}...
AbstractWe study ω-hypoelliptic differential operators of constant strength. We show that any operat...
AbstractWe prove Gevrey regularity for a class of operators defined on the torus Tm+n, with real ana...
summary:The problems of Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators a...
none1noWe study the problem of perturbations of C∞ -hypoelliptic operators by lower order terms. We ...
1.1. In the study of the regularity of generalized solutions of various problems for partial differe...
A linear different operator L is called weakly hypoelliptic if any local solution u of Lu=0 is smoot...
This is a survey paper about the proof of the hypoellipticity theorem by Hörmander (Acta Math. 1967)...
AbstractIt is shown that the natural analogue of Liouville's theorem holds for the well-known hypoel...
none2noWe study the problem of perturbations of $ C^\infty $-hypoelliptic operators by lower order t...
AbstractLet P be a left-invariant differential operator on the Heisenberg group Hn, P homogeneous wi...
Let $P(x, D)$ be a partial differential operator with principal symbol $p_m(x, \xi)=q_{m-l}(x, \xi)a...
We study C∞ and analytic hypoellipticity for an invariant class of operators with multiple ch...
We study, for a model class of classical pseudodifferential operators with symplectic characteristic...
Fedii [1] studied hypoellipticity for operators of the form L=D21+ф(x1)2D22 in R2, and proved that L...
We study the hypoellipticity for the operator (1) $P=D_{t}+i\alpha(t)b(t, X, D_{x}) $ in $\mathrm{R}...
AbstractWe study ω-hypoelliptic differential operators of constant strength. We show that any operat...
AbstractWe prove Gevrey regularity for a class of operators defined on the torus Tm+n, with real ana...
summary:The problems of Gevrey hypoellipticity for a class of degenerated quasi-elliptic operators a...
none1noWe study the problem of perturbations of C∞ -hypoelliptic operators by lower order terms. We ...
1.1. In the study of the regularity of generalized solutions of various problems for partial differe...
A linear different operator L is called weakly hypoelliptic if any local solution u of Lu=0 is smoot...
This is a survey paper about the proof of the hypoellipticity theorem by Hörmander (Acta Math. 1967)...
AbstractIt is shown that the natural analogue of Liouville's theorem holds for the well-known hypoel...
none2noWe study the problem of perturbations of $ C^\infty $-hypoelliptic operators by lower order t...
AbstractLet P be a left-invariant differential operator on the Heisenberg group Hn, P homogeneous wi...
Let $P(x, D)$ be a partial differential operator with principal symbol $p_m(x, \xi)=q_{m-l}(x, \xi)a...
We study C∞ and analytic hypoellipticity for an invariant class of operators with multiple ch...
We study, for a model class of classical pseudodifferential operators with symplectic characteristic...
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