Book review: ‘Quantum in Pictures’

The latest work by computer scientists Bob Coecke and Stefano Gogioso, ‘Quantum in Pictures’, aims to make the quantum world more accessible and inclusive. So, whether you’re a high school student or a science enthusiast, the authors are confident that anyone mastering the tools in the book will gain an understanding equivalent to that of a quantum mechanics graduate at university. But what if a complete novice in quantum computing, i.e., this reviewer, could gain a genuine understanding of the field by simply reading this book? Let’s test this out, shall we?

Full disclosure from the get-go, I have absolutely no prior knowledge or expertise in quantum computing, therefore Coecke and Gogioso’s latest research and book is not only worthy of a review but also a lesson for someone who barely scraped a C in GSCE Maths – a learning curve, if you will.

For context, ‘Quantum in Pictures’ is the brainchild of Quantinuum’s chief scientist Professor Bob Coecke and Dr Stefano Gogioso of Oxford University. The book introduces a formalism for quantum mechanics based on using ‘ZX-calculus’ (or ‘ZX’), to describe quantum processes.

ZX-calculus was originally introduced around 15 years ago by Coecke and Ross Duncan, the head of quantum software at Quantinuum, when they were colleagues in the now Computer Science department at Oxford University. ZX is based on a novel system of pictures instead of formal, traditional mathematics.

As described in ‘Quantum in Pictures’, ZX-calculus comes equipped with all the mathematical rules required to handle quantum mechanics. But “doing the mathematics of quantum mechanics with ZX-calculus differs greatly from the way it is taught today. ZX uses a method known as picturalism: manipulating shapes, connected by lines, according to a set of five rules. These include fusion, copying, colour changing, square-popping and phase-swapping.”

It’s clear how much dedication and time Coecke and Gogioso have invested in making the subject area accessible throughout this book, especially since the education system has given maths a ‘Marmite’ reputation – making it hard for many people, including myself, to understand maths, resulting in many of us not appreciating it and wanting to ditch the subject as soon as we can.

‘Quantum in Picture’, however, could change this – the book gradually helps the reader gain an understanding of quantum computing through a step-by-step guide. The simple pictures seen throughout the book aren’t only there for illustrative purposes, but Coecke and Gogioso have developed and used a rigorous ‘language’ that can, apparently, be used for all sorts of maths education.

When reading this book, there were many instances where I had to go back to wrap my head around the concepts Coecke and Gogioso illustrated throughout the book. However, the illustrations themselves certainly helped me gain a better understanding of the subject than any numbers and formulas on the page could ever achieve. I think that’s the problem with maths too, all the different signs and formulas put many people off – so the pictures certainly help ease that anxiety of seeing signs they do not understand.

So, does ‘Quantum in Pictures’ help novices like me gain a better understanding of quantum? In short, it can. It’s essentially ‘quantum computing for dummies’ like myself who are curious about the concepts surrounding this form of maths but left the subject way back in their school days (I mean this in the nicest way possible). That’s not to say that people with amateur or specialty surrounding the concepts cannot engage in this book. In fact, the reviewer would say that the book would be the perfect tool for younger people who wish to learn more about the subject area and equally specialists that wish for a refresher.

The book offers a great opportunity to inspire and educate the younger, and not-so-young, generations who merely like to dabble briefly in the subject or perhaps open up possibilities for career pathways without making the maths scary. After all, some say that quantum is the future, right?