A Revolution

The theory of Quantum Mechanics was developed around 1900, and provided explanations to the black-body radiation problem by Max Planck in 1900, thus resolving the ultraviolet catastrophe, and to the photoelectric effect by Albert Einstein in 1905.

The motivation for this theory were experiments, whose strange results needed fundamentally new concepts. It was the work of many, and the result of intense debates between bright physicists such as Niels Bohr, Werner Heisenberg, Erwin Schrödinger, Paul Dirac, Wolfgang Pauli, just to name a few of them. All of the just named (!), and many more all over the 20th century, were awarded the Nobel prize.

In the 1950s and 1960s, groundbreaking technologies like transistors or lasers were developed, that all rely on quantum-mechanical effects. These were significant contributions to computing and communication. At the same time models and technologies for superconductivity and Nuclear magnetic resonance (NMR) were developed. Both can only be explained with Quantum Mechanics. Magnetic resonance imaging (MRI) wouldn’t be possible without them. Did you know that MRI “is the leading commercial large-scale application of superconductivity”? [84] The emergence of all these technologies is sometime referred as the “First Quantum Revolution”. It is, in some sense, Quantum 1.0.

The fathers of Quantum Mechanics themselves noticed that their theory lead to strange results, when they thought about single particles, so-called Gedankenexperiments. This weirdness is due to the concepts of superpositions and entanglement, that will be described below. Beginning in the 1980s, technological progress made it possible to isolate individual atoms and photons, for example in optical cavities by Serge Haroche (again a Nobel prize). It was now possible to realize these Gedankenexperiments, and to demonstrate that the weird concepts of Quantum Mechanics really apply!

The next step was to control these quantum phenomena, and to make advantage of them and create devices exploiting this weirdness. This is what have happened since these first quantum optical experiments, and finally lead to the “Second Quantum Revolution”: The emergence of Quantum Computing and Quantum Communication.

Quantum 2.0 has been released! 1

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References: Inspired by [M18] and [B2].

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At least the developer version :)