Reversible Computing Systems, Logic Circuits, and Cellular Automata

Reversible computing is a paradigm of computation that reflects physical reversibility, and will become important when we develop future computing systems that directly utilize microscopic physical phenomena for logical operations. In this survey we discuss, from a theoretical point of view, how a reversible computer is implemented as a reversible logic circuit, how a reversible logic circuit is composed of reversible logic elements, and how a reversible logic element can be realized in a physically reversible system. We shall see that, in spite of the constraint of reversibility, universal reversible computers can be constructed by very simple reversible primitives, and that in these systems computation is often carried out in a very unique and different manner from conventional computing systems.