Abstract
The first lesson was devoted to a discussion of the differences between classical and quantum bits, followed by a review of the elementary operations underlying classical calculus. The aim of this reminder was to introduce the fundamental concept of a set of universal operations on which the notion of algorithm is built. Another key idea introduced in this lesson was that of reversible elementary operations, essential for understanding the transition from classical to quantum operations. In a classical random access memory, such as the data register of a microcomputer processor, an information bit is represented by a system of two stable states separated by a potential barrier. Thus, in the flip-flop CMOS circuit, the two attractors correspond to two voltage states of the electrical node located between two complementary transistors. Writing a bit value, such as zero, means placing the system in the state conventionally chosen to represent zero. The Boolean operation NO corresponds to switching the system from one state to the other. The dissipative nature of the classical system is crucial.
