The Bare Minimum of Quantum Computers, Understood at a Glance Without Equations

CHAPTER 01 — 100 Years of Quantum Mechanics

What the World Is Made Of

The ancient Greek philosopher Democritus proposed that all matter is made of "atoms," smallest units that cannot be divided any further, and that the world consists broadly of two things: matter and light. Matter and light seem to have entirely different natures, but when we look at how they behave in the microscopic world, they share a surprising trait: light sometimes behaves like a particle, and particles such as electrons sometimes behave like waves. Something that has both particle and wave properties is called a "quantum," and the most fundamental physical law that explains the microscopic world in a unified way on the basis of this duality is "quantum mechanics," born in the early twentieth century. The history of quantum mechanics can be divided into three stages: the "growth period" from the early twentieth century to the 1930s, the "first quantum revolution" lasting until the 1980s, and the "second quantum revolution" from the 1990s to the present.

Physics That Changed Society / Max Planck, Father of Quantum Mechanics

The birth of quantum mechanics is closely tied to industry.