arXiv subjects
Publications and source records attributed to Rüya Üster.
We establish continuity and Schatten-von Neumann properties for Fourier integral operators with amplitudes in Orlicz modulation spaces, when acting on other Orlicz modulation spaces themselves. The phase functions are non smooth and admit second order derivatives in suitable classes of modulation spaces.
We deduce continuity properties for pseudo-differential operators with symbols in Orlicz modulation spaces when acting on other Orlicz modulation spaces. In particular we extend well-known results in the literature. We also show that the entropy functional is continuous on a suitable Orlicz modulation space between $M^p$ and $M^2$ when $p<2$, though the functional is discontinuous on $M^2=L^2$.
We deduce continuity properties for pseudo-differential operators with symbols in quasi-Banach Orlicz modulation spaces when rely on other quasi-Banach Orlicz modulation spaces. In particular we extend certain results in \cite{GH1,GH2,Toft2,Toft10,Toft16}.
We show that a smooth function $f$ on $\mathbf R^d$ belongs to the Pilipovi{ć} space $\mathcal H_{\flat _σ}(\mathbf R^d)$ or the Pilipovi{ć} space $\mathcal H_{0,\flat _σ}(\mathbf R^d)$, if and only if the $L^p$ norm of $H_d^Nf$ for $N\ge 0$, satisfy certain types of estimates. Here $H_d=|x|^2-Δ_x$ is the harmonic oscillator.
We deduce continuity, compactness and invariance properties for quasi-Banach Orlicz modulation spaces. We characterize such spaces in terms of Gabor expansions and by their images under the Bargmann transform.