Periodic hyperfunctions and Fourier series

Fourier transformation of Sato’s hyperfunctions

A new generalized function space in which all Gelfand-Shilov classes S ′0 α (α > 1) of analytic functionals are embedded is introduced. This space of ultrafunctionals does not possess a natural nontrivial topology and cannot be obtained via duality from any test function space. A canonical isomorphism between the spaces of hyperfunctions and ultrafunctionals on R is constructed that extends the...

Structural Theorems for Families of Fourier Hyperfunctions

Determination of a jump by Fourier and Fourier-Chebyshev series

‎By observing the equivalence of assertions on determining the jump of a‎ ‎function by its differentiated or integrated Fourier series‎, ‎we generalize a‎ ‎previous result of Kvernadze‎, ‎Hagstrom and Shapiro to the whole class of‎ ‎functions of harmonic bounded variation‎. ‎This is achieved without the finiteness assumption on‎ ‎the number of discontinuities‎. ‎Two results on determination of ...

On localization properties of Fourier transforms of hyperfunctions

In [Adv. Math. 196 (2005) 310–345] the author introduced a new generalized function space U(Rk) which can be naturally interpreted as the Fourier transform of the space of Sato’s hyperfunctions on Rk. It was shown that all Gelfand–Shilov spaces S′0 α (R k) (α > 1) of analytic functionals are canonically embedded in U(Rk). While the usual definition of support of a generalized function is inappl...

Right inverses for partial differential operators on Fourier hyperfunctions

We characterize the partial differential operators P (D) admitting a continuous linear right inverse in the space of Fourier hyperfunctions by means of a dual (Ω)-type estimate valid for the bounded holomorphic functions on the characteristic variety VP near R . The estimate can be transferred to plurisubharmonic functions and is equivalent to a uniform (local) Phragmén–Lindelöf-type condition.