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Introduction to Quantum Computing and Blockchain

It was the best of times, it was the worst of times,
it was the age of wisdom, it was the age of foolishness,
it was the epoch of belief, it was the epoch of incredulity,
it was the season of Light, it was the season of Darkness,
it was the spring of hope, it was the winter of despair.

I am sure Charles Dickens did not foresee quantum computing or Blockchain. His words from 160 years ago, however, still apply to the ebbs and flows we have seen with these two technologies. Quantum computing has been around for a good part of a century. In contrast, Blockchain was first introduced to the world in 2008.

Unlike the Blockchain wave that has hit us in recent years, quantum principles have been around for several decades. Quantum physics has been a very debated field and is fundamental to quantum computing. However, the field of quantum computing has gained momentum in recent times.

Despite the differences in the age of the two technologies, they have had interesting histories. For instance, most people who understand Blockchain agree that the framework is robust. However, the technology is still far from perfect, and that is true for quantum computing too.

The momentum behind quantum computing in the past decade has been largely due to advancements in algorithms and infrastructure. However, in my opinion, it is also because of the data age we live in, and some of the use cases for quantum computers are becoming clearer and relevant. In this chapter, I will cover the history of both these technologies that have had controversial pasts. Their place in modern society as transformational technologies is hard to dispute.