What if someone told you the material world does not exist? That everything we take for objective physical phenomena actually only exists in relation to us or some other object? And what if they told you this with a great smile and in a way the is really convincing and not unnecessarily convoluted?

I bought this book together with a ticket to a Guardian talk with Carlo Rovelli. After over a year of the pandemic, I am at my wit’s end as to how to entertain my brain sometimes. I’ve gone through the theatre online phase, then cleaning my Netflix list, books of course, but after 15 months it all starts feeling a bit repetitive. So then I decided to explore lectures and talks, when I came to London I was going to the Royal Society talks every few months and thought attending some lectures again may be a good distraction. And a book coming with it could not be a bad thing.

The talk was great, Rovelli is a lovely person, full of smiles and very approachable, especially when you factor in that he is a theoretical physicist. He was very open and his endless fascination with the topic he studies comes through in every sentence. After the talk, I couldn’t wait to read the book, especially that throughout the years I had a few bookish encounters with quantum mechanics. As much as I cannot fully grasp the maths and physics calculations behind it the concept always fascinated me and I love when someone is able to explain it in plain English. One of such books was Quantum: Einstein, Bohr and the Great Debate About the Nature of Reality by Manjit Kumar. 

Helgoland focuses on the breakthrough achieved by Heisenberg during his stay on the island of Helgoland. Obviously, it was a group effort, Heisenberg worked with Max Born and others, on a problem identified by Niels Bohr. But the breakthrough of the matrix formulation of quantum mechanics came to him on that lonely almost hostile island. 

Rovelli tries to bring the scientific progress achieved in those tumultuous years closer to us. The rigor of Heisenberg rejecting any assumptions and focusing only on what’s observable, and taking this as his starting point. The idea of noting the previous and current position of the electron in a set of rows and columns. His struggle with the fact that it somehow was non-commutable (as matrices are, but he didn’t know this until he finally contacted mathematicians). 

What is amazing is that Rovelli is able to explain all of it in really plain language. He boils some of the most complex problems physics had to deal with down to basics that anyone can grasp. But Heisenberg’s story is only a starting point because there is more ideas that Rovelli wants to tell us and have us consider. 

As much as Heisenberg & Co. gave us quantum mechanics there is still this chasm between quantum physics and macro physics, they seem to be guided by different principles, but this would mean one of them is wrong. Until you consider various interpretations of quantum mechanics, and Rovelli deftly guides us through a few. But his goal is to take us to the relational interpretation. 

Relational interpretation is very simple in principle, but it rocks our world to the core. The idea is that objects exist and have characteristics only in relation to one another. It is so simple and yet has such profound consequences. It means that an object that exists in no relation to another, i.e. is not perceived, does not emit light, has no impact or manifestation to another object, in fact, does not exist. It reminded me (on a very different scale, of course) of the ‘If a tree falls in a forest and no one is around to hear it, does it make a sound?’ thought experiment. If you take this reasoning further there is no objective reality, there’s only a series of relational perceptions, each between a pair of objects, no matter what scale they are. 

That also blows up another thing that science was for a long time taking for granted: that is you know the past conditions, and know the current ones you should be able to predict the future. And yet we cannot. Relational interpretation does away with the entire idea. Our predictions are always just probabilities, not certainties. The biggest challenge of that interpretation is the fact that we have to accept that what we perceive exists just for us. One of the examples Rovelli uses is a different perception of color by different species. We see red objects in a very different way to our dogs, so who sees them objectively? No one. Both our perceptions are true, each in relation to a different object. 

It’s such a fascinating topic I can go on and on. But I’ll stop here not to bore you to tears, and also because Rovelli writes about it in so much more entertaining way. He also throws his net wide and brings us an array of philosophical takes on the matter.

During the talk, Rovelli mentioned that his book speaks mostly to people who know nothing about quantum mechanics or to scientists active in the field. People who know something can be annoyed by the simplicity of the book. And it is very true, I was at times annoyed but the fair warning helped. And it is so worth the read. 

Similar to The Three-Body Problem it made me take a step back and look a bit more suspiciously at things we take for granted. Also, the relational interpretation was not completely new to me, actually, I read about it a few months ago, in a very different context, in The Tyranny of Reality by Mona Chollet. 
You can find Rovelli’s talks on youtube and they are really worth a watch, rarely do you find someone with so much enthusiasm. I always think that if I was lucky enough to have such passionate teachers of maths and physics in school my career might have been completely different. It’s not a regret, for I enjoy my life a lot, but rather a past opportunity I sometimes enjoy theorizing about.

Photo by Violetta Kaszubowska