Quantum Computing and Communications: An Engineering Approach

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Motivations

1.1 LIFE CYCLE OF A WELL-KNOWN INVENTION

Every invention/technology has its own life cycle, similar to a human being. It can be shorter or longer but all of them have common phases and stages. Let us summarize this evolution using the well-known example of steam engine. First, scientists spend lots of time to find out something new. In our case Heron, a most famous experimenter, designed and implemented a steam-engined ball named Heron's ball (see Fig. 1.1).

Once a new idea has been born a long period of time is required until the stage when size, cost, efficiency, etc. of pieces of this equipment reach a minimally required and acceptable level. Many amateurs and experts devote their life to fulfil these requirements representing the childhood of the technology. The way is paved with many failures and rare successes therefore most of them remain anonymous forever. However, one day a clever guy manages to combine the small pieces of former results and adds something to them thus finally he/she succeeds. Concerning our example James Watt built the first working steam engine in 1765. Thanks to Mr. Watt steam technology attained its majority.

In the third phase the technology emerges from the deep of dark and mysterious laboratories and begins spreading among everyday people. Fulton's ship Clermont in 1807 irreversibly ended the glorious age of sailing ships and men of war while Stephenson's Rocket in 1829 convinced the skeptics that railway would be the leading transportation ...