Asymptotic Fourier and Laplace transforms for vector-valued hyperfunctions

Vector-valued Laplace Transforms and Cauchy Problems

This monograph gives a systematic account of the theory of vector-valued Laplace transforms, ranging from representation theory to Tauberian theorems. In parallel, the theory of linear Cauchy problems and semigroups of operators is developed completely in the spirit of Laplace transforms. Existence and uniqueness, regularity, approximation and above all asymptotic behaviour of solutions are stu...

Asymptotic hyperfunctions, tempered hyperfunctions, and asymptotic expansions

We introduce new subclasses of Fourier hyperfunctions of mixed type, satisfying polynomial growth conditions at infinity, and develop their sheaf and duality theory. We use Fourier transformation and duality to examine relations of these asymptotic and tempered hyperfunctions to known classes of test functions and distributions, especially the Gel’fand-Shilov spaces. Further it is shown that th...

Asymptotic Laplace Transforms and Evolution Equations

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...

Extremal Vector Valued Inequalities for Hankel Transforms

The disc multiplier may be seen as a vector valued operator when we consider its projections in terms of the spherical harmonics. In this form, it represents a vector valued Hankel transform. We know that, for radial functions, it is bounded on the spaces Lplq (r n−1 dr) when 2n n+1 < p, q < 2n n−1 . Here we prove that there exist weak-type estimates for this operator for the extremal exponents...