Representation of quasianalytic ultradistributions
ABSTRACT We give the following representation theorem for a class containing quasianalytic ultradistributions and all the non-quasianalytic
ultradistributions: Every ultradistribution in this class can be written as
u = P(D)g(x) + h(x)u = P(\Delta )g(x) + h(x)
whereg(x) is a bounded continuous function,h(x) is a bounded real analytic function andP(d/dt) is an ultradifferential operator. Also, we show that the boundary value of every heat function with some exponential growth
condition determines an ultradistribution in this class. These results generalize the theorem of Matsuzawa [M] for the above
class of quasianalytic ultradistributions and partially solve a question of A. Kaneko [Ka]. Our interest lies in the quasianalytic
case, although the theorems do not exclude non-quasianalytic classes.