By Bob
To write a book, you have to start writing. This is obvious, but no less true and important. In the summer of 2018, I started writing what I thought would be the introduction to the book. My perspective was, and is, very much from the mathematical and computer science directions. To be clear, I am not a physicist. If I could produce a coherent introduction to what I thought the book would cover, I might convince myself that it would be worth the hundreds of hours it would take to complete the project.
When I recently announced that the book was available for pre-order, my industry colleague Jason Bloomberg asked:
“So where does it fall on the spectrum between ‘totally accurate yet completely impenetrable’ and ‘approachable by normal humans but a complete whitewash’?”
I responded:
“I bring you along … to give you the underlying science of quantum computing so you can then read the “totally accurate but formally impenetrable” texts.”
I decided that I would cover the basic math necessary to understand quantum computing, and then get into quantum bits (qubits), gates, circuits, and algorithms. Although readers with the necessary background (or perhaps a good memory of that background) can skip the mathematical fundamentals, I decided to take people through the algebra and geometry of complex numbers, linear algebra, and probability necessary to understand what qubits are and what you can do with them.
