Quantum Computation Explained to My Mother

There are many falsely intuitive introductions to quantum theory and quantum computation in a handwave. There are also numerous documents which teach those subjects in a mathematically sound manner. To my knowledge this paper is the shortest of the latter category. The aim is to deliver a short yet rigorous and self-contained introduction to Quantum Computation, whilst assuming the reader has no prior knowledge of anything but the fundamental operations on real numbers. Successively I introduce complex matrices; the postulates of quantum theory and the simplest quantum algorithm. The document originates from a fifty minutes talk addressed to a non-specialist audience, in which I sought to take the shortest mathematical path that proves a quantum algorithm right.