Zobrazeno 1 - 10
of 128
pro vyhledávání: '"Sjoestrand, Johannes"'
The purpose of this paper is to revisit the proof of the Gearhart-Pr\"uss-Huang-Greiner theorem for a semigroup $S(t)$, following the general idea of the proofs that we have seen in the literature and to get an explicit estimate on the operator norm
Externí odkaz:
http://arxiv.org/abs/2303.12435
Autor:
Sjöstrand, Johannes, Vogel, Martin
We study the small singular values of the $2$-dimensional semiclassical differential operator $P = 2\,\mathrm{e}^{-\phi/h}\circ hD_{\overline{z}}\circ \mathrm{e}^{\phi/h}$ on $S^1+iS^1$ and on $S^1+i\mathbb{R}$ where $\phi$ is given by $\sin y$ and b
Externí odkaz:
http://arxiv.org/abs/2303.06096
We study Toeplitz operators on the Bargmann space, with Toeplitz symbols given by exponentials of complex quadratic forms. We show that the boundedness of the corresponding Weyl symbols is necessary for the boundedness of the operators, thereby compl
Externí odkaz:
http://arxiv.org/abs/2303.01558
We study Toeplitz operators on the Bargmann space, with Toeplitz symbols that are exponentials of complex quadratic forms, from the point of view of Fourier integral operators in the complex domain. Sufficient conditions are established for the compo
Externí odkaz:
http://arxiv.org/abs/2205.08649
The study of complex geometric optics solutions to a system of d-bar equations appearing in the context of electrical impedance tomography and the scattering theory of the integrable Davey-Stewartson II equations for large values of the spectral para
Externí odkaz:
http://arxiv.org/abs/2203.14650
Autor:
Helffer, Bernard, Sjöstrand, Johannes
The purpose of this paper is to revisit the proof of the Gearhardt-Pr\"uss-Hwang-Greiner theorem for a semigroup $S(t)$, following the general idea of the proofs that we have seen in the literature and to get an explicit estimate on $\Vert S(t) \Vert
Externí odkaz:
http://arxiv.org/abs/2103.06792
In a previous work on the large $|k|$ behavior of complex geometric optics solutions to a system of d-bar equations, we treated in detail the situation when a certain potential is the characteristic function of a strictly convex set with real-analyti
Externí odkaz:
http://arxiv.org/abs/2010.04423
We study semiclassical Gevrey pseudodifferential operators acting on the Bargmann space of entire functions with quadratic exponential weights. Using some ideas of the time frequency analysis, we show that such operators are uniformly bounded on a na
Externí odkaz:
http://arxiv.org/abs/2009.09128
We study semiclassical Gevrey pseudodifferential operators, acting on exponentially weighted spaces of entire holomorphic functions. The symbols of such operators are Gevrey functions defined on suitable I-Lagrangian submanifolds of the complexified
Externí odkaz:
http://arxiv.org/abs/2009.09125
We develop a direct approach to the semiclassical asymptotics for Bergman projections in exponentially weighted spaces of holomorphic functions, with real analytic strictly plurisubharmonic weights. In particular, the approach does not rely upon the
Externí odkaz:
http://arxiv.org/abs/2004.14606