Cosmic wonder: a review of Carlo Rovelli's "Seven Brief Lessons on Physics"

There is a “colorful and amazing world where universes explode,” a mysterious place where splashes of galaxies move like waves and there is no such thing as true emptiness even when it feels like there is. That world is ours, and Carlo Rovelli’s “Seven Brief Lessons on Physics” -- a real understatement of a title -- is our soulful guide, leading the curious through the origin stories, essential components, and ongoing debates surrounding general relativity, quantum mechanics, elementary particles, and other theoretical building blocks of modern physics.

The short book is not just any primer for those of us whose heads rest above the clouds of the physics world; it is written in our native tongue of artful prose, rooted in curious wonder that grows exponentially with each question it answers, cushioned with humility, and framed by humanity. “Perhaps it is we who have not yet learned to look at it from just the right point of view,” muses Rovelli on the Standard Model. He continues:

“For now, this is what we know of the matter: A handful of types of elementary particles, which vibrate and fluctuate constantly between existence and nonexistence and swarm in space, even when it seems that there is nothing there, combine together to infinity like the letters of a cosmic alphabet to tell the immense history of galaxies; of the innumerable stars; of sunlight; of mountains, woods, and fields of grain; of the smiling faces of the young at parties; and of the night sky studded with stars.”

Here, Rovelli is no ideologue. Rather, he shares with us what he has learned in his years of immersion in theoretical physics in the way that ever-unquenchable thinkers share a brilliant yet fragile idea; his words shimmer with hope that we will see what he sees, and even before we do, he wonders aloud what else there may be. In each discovery he gracefully conveys, he rediscovers along with us. “The heat of black holes is like the Rosetta stone of physics,” he writes to his own awe, “still awaiting decipherment in order to reveal the true nature of time.”

In order to spare those who seek only a traditional meta-level reflection that we expect when it comes to books, I’ve waited until now to bring up one challenge regarding this ‘true nature of time’. It’s a critique whose specificity, I think, represents an admitted overstepping as my role of reviewer. That’s the first problem with what I’m about to say. The second is that I know next to nothing of physics nor philosophy compared to Mr Rovelli, and it is my understanding that amateurs thinking they have found a flaw in the laws of physics is a common, painful thorn in the side of those who have dedicated their lives to the phenomenon. But it’s one that I can’t resist. Now that I’ve apologized for my sin, I’ll commit it.

In Rovelli’s sixth lesson, he presents the possibility that the flow of time is an illusion, much the like the misguided feeling that the world is flat. He writes that our discussion of past versus present in a manner similar to discussing here versus there is flawed. “For a hypothetically super-sensible being [that is, a thing that somehow perceives beyond what it experiences], there would be no ‘flowing’ of time,” Rovelli writes, “the universe would be a single block of past, present, and future. But due to the limitations of our consciousness we perceive only a blurred vision of the world and live in time…. Is that clear? No, it isn’t. There is so much still to be understood.”

At least he admits that last bit.

Rovelli’s discussion of time feels murky and underexplored. The physicist essentially tells us that he suspects heat is the key to differentiating between past and future. For a book that is meant to break obtuse ideas into digestible morsels, this explanation felt stale. If heat is the motion of atoms, then what we are really talking about is change, aren’t we? Why not discuss the incredible (and accessible) idea that we only experience time as relative to change?

Rovelli had introduced this confusing lesson with the following statement: “It is possible to imagine a world without colors, without matter, even without space, but it’s difficult to imagine one without time.” I scribbled in the margins: “Because time is the phenomenon of things we experience (color, matter, location) changing. Time is not a characteristic that exists independently; it is an experience entirely relative to the things that we do indeed isolatably experience.” This is why we are able to so clearly imagine — yet never experience — time freezing. Time freezing would be how we would describe every single aspect of the entire universe stopping, not changing one bit. If you or I lost consciousness and the world continued on, we would be frozen but time would continue to exist. Whenever we regained consciousness, such as when we awake in the morning, we would experience the perception that things had changed, from the micro level of our own body’s cells degrading and regenerating to the macro level of the sun’s location in the sky having shifted. It would feel like time had passed. But if we lost consciousness and every single sub-atomic particle in the entire universe, from oceans to air to stars to dust to the cells in our bodies, stopped  — froze, did not change in its location or other characteristics, however you want to say it — I would like to suggest that there would have been no time. If the universe began moving again — creating heat, as Rovelli so opaquely referred to it — at the same time that we regained consciousness, I do not believe it would feel as if any time had passed. To me, time is like one of those amazing German combo-words, like “Schadenfreude,” which is defined as the pleasure derived from misfortune. Imagine trying to discuss the experience of schadenfreude as a feeling that would exist on its own separate from the things that constitute it: pleasure and misfortune. When we try to understand time as a dimension isolatable from states of being and their change (the two things I’m asserting that time is the interaction of), it is as confounding as trying to understand schadenfreude divorced from pleasure or misfortune. Unintentionally, the discussion has been structured to be an ontological cycle of conflation. That is my admittedly preferred explanation for why I faltered during an otherwise immaculate journey through the stunning, crystal-clear waters that is Rovelli’s exploration of our current understanding of physics. Regardless, what a profound journey it was.

Aside from that little hiccup I feel an obligation to admit I experienced, I can’t and should not analyze the academic rigor of Seven Brief Lessons on Physics -- it just isn’t my place -- but what I can speak to is what it feels like to read this book. Despite its highly intellectual nature, Rovelli’s words feel like poetry. They feel religious. In his attempts to explain where we come from, how we move, what time feels like, the Italian physicist injects fresh wonder into our view of the world. Reading the book feels like looking up at the night stars themselves.

It is that feeling that the book’s true value lies in. These days, we could find on our own many of the essential summaries that Rovelli provides us with. Explanations of gravity and quantum mechanics aren’t hard to come by. But for many of us, such gross access to information has turned into white noise, so Rovelli’s enthusiastic and patient curation is most welcome. Read this book to bathe in the feeling that you are a part of something wondrous, and that perhaps how this is possible can be grasped after all.