This volume develops a systematic study of time-dependent control processes. The basic problem of null controllability of linear systems is first considered. Us

This volume develops a systematic study of time-dependent control processes. The basic problem of null controllability of linear systems is first considered. Us

If $G$ is a reductive algebraic group acting rationally on a smooth affine variety $X$, then it is generally believed that $D(X) $ has properties very similar t

A long open problem in probability theory has been the following: Can the graph of planar Brownian motion be split by a straight line? In this volume, the autho

In this volume, the authors address the following: Let $A$ be a Banach algebra, and let $\sum\:\ 0\rightarrow I\rightarrow\frak A\overset\pi\to\longrightarrow A