Results 41 to 50 of about 125 (119)
On a criterion for hypoellipticity
Proceedings of the Japan Academy, Series A, Mathematical Sciences, 1986 Consider \(\Omega \subset R^ n\) an open set and \(P=p(x,D_ x)\) a second order differential operator with real valued coefficients in \(C^{\infty}(\Omega)\). Assume that for any \(\epsilon >0\) and any compact \(K\subset \Omega\) there is a constant C(\(\epsilon\),K) such that \[ \| (\log (| D_ x|^ 2+1))^ 2u\| \leq \| \epsilon p(x,D_ x)u\| +C\| u ...
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Horizontally Affine Functions on Step-2 Carnot Algebras. [PDF]
J Geom Anal, 2023 Le Donne E, Morbidelli D, Rigot S.
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Active thermal cloaking and mimicking. [PDF]
Proc Math Phys Eng Sci, 2021 Cassier M +3 more
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A Cortical-Inspired Sub-Riemannian Model for Poggendorff-Type Visual Illusions. [PDF]
J Imaging, 2021 Baspinar E +3 more
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On a problem of hypoellipticity
Kyoto Journal of Mathematics, 1987 The author presents a proof of the following result. Let P(x,D) be an m- th order partial differential operator of principal type with analytic coefficients in an open subset \(\Omega\) of \({\mathbb{R}}^ n\). If P is not hypoelliptic in \(\Omega\), there exists an open subset \(\omega_ 0\) and \(\Omega\) such that, for any \(\ell \geq m\), one can ...
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Stochastic dynamics of human papillomavirus delineates cervical cancer progression. [PDF]
J Math Biol, 2023 Phan TA, Sarower F, Duan J, Tian JP.
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Hypoellipticity on Cauchy-Riemann Manifolds [PDF]
Transactions of the American Mathematical Society, 1992 Using a recent homotopy formula by Trèves, it is shown that the existence of ( q + 1 )
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Criteria for Hypoellipticity of Differential Operators
Publications of the Research Institute for Mathematical Sciences, 1986 The author studies \(L^ 2\) estimates which imply hypoellipticity of partial differential operators. As a consequence he proves e.g. the hypoellipticity of the operators \[ D_ 1^{2\ell}+D_ 2^{2\ell}+\exp (-| x_ 1|^{-\delta})D_ 3^{2\ell}\quad in\quad {\mathbb{R}}^ 3,\quad \ell \in {\mathbb{Z}}^+/\{0\},\quad ...
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Gevrey Hypoellipticity for Grushin Operators
Publications of the Research Institute for Mathematical Sciences, 1997 The author studies analytic and Gevrey hypoellipticity of operators of the type \[ P= \sum C_{\alpha\beta\gamma} y^\alpha D^\beta_x D^\gamma_y, \] where \(x\in \mathbb{R}^n\), \(y\in\mathbb{R}^m\), and the sum is finite, satisfying suitable conditions as in \textit{V. V. Grušin} [Math. USSR Sbornik 17, 497-514 (1972; 255.35022)].
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Analytic Torsion of Generic Rank Two Distributions in Dimension Five. [PDF]
J Geom Anal, 2022 Haller S.
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