What do you think?
Rate this book
Everything you need to know about modern physics, the universe and your place in the world in seven enlightening lessons
'Here, on the edge of what we know, in contact with the ocean of the unknown, shines the mystery and the beauty of the world. And it's breathtaking'
These seven short lessons guide us, with simplicity and clarity, through the scientific revolution that shook physics in the twentieth century and still continues to shake us today. In this beautiful and mind-bending introduction to modern physics, Carlo Rovelli explains Einstein's theory of general relativity, quantum mechanics, black holes, the complex architecture of the universe, elementary particles, gravity, and the nature of the mind. In under eighty pages, readers will understand the most transformative scientific discoveries of the twentieth century and what they mean for us. Not since Richard Feynman's celebrated best-seller Six Easy Pieces has physics been so vividly, intelligently and entertainingly revealed.
108 pages, Kindle Edition
First published October 22, 2014
A university student attending lectures on general relativity in the morning and others on quantum mechanics in the afternoon might be forgiven for concluding that his professors are fools, or have neglected to communicate with each other for at least a century. In the morning the world is curved space where everything is continuous; in the afternoon it is a flat space where quanta of energy leap.
The paradox is that both theories work remarkably well. Nature is behaving with us like that elderly rabbi to whom two men went in order to settle a dispute. Having listened to the first, the rabbi says: ‘You are in the right.’ The second insists on being heard, the rabbi listens to him and says: ‘You’re also right.’ Having overheard from the next room the rabbi’s wife then calls out, ‘But they can’t both be in the right!’ The rabbi reflects and nods before concluding: ‘And you’re right too.’
The confusion between these two diverse human activities—inventing stories and following traces in order to find something—is the origin of the incomprehension and distrust of science shown by a significant part of our contemporary culture. The separation is a subtle one: the antelope hunted at dawn is not far removed from the antelope deity in the night’s storytelling.
The border is porous. Myths nourish science, and science nourishes myth. But the value of knowledge remains. If we find the antelope, we can eat.
“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.“
Pretty nebulae.... because look how cool they are!
¹ Apparently time flows² faster up high - faster in the mountains than at the sea level.I’ve read a few of physics-y popular science books — and this one is very different. It’s certainly the most poetic of them all. It does not as much explain as just present the ever-crazier (except completely scientific) ideas about the fabric of the world that, if I really stop to think about them, is brain-melting stuff. And then it waxes philosophically and wonderfully, and asks us to keep exploring, keep wondering, keep on with the curiosity that had driven humanity since the start, in all this “granular structure of space”.
² Except that time doesn’t really *flow*. Or exist. It’s just that our consciousness is limited. Also, heat is involved.
“Ever since we discovered that Earth is round and turns like a mad spinning-top, we have understood that reality is not as it appears to us: every time we glimpse a new aspect of it, it is a deeply emotional experience. Another veil has fallen.“
“When we talk about the big bang or the fabric of space, what we are doing is not a continuation of the free and fantastic stories that humans have told nightly around campfires for hundreds of thousands of years. It is the continuation of something else: of the gaze of those same men in the first light of day looking at tracks left by antelope in the dust of the savannah—scrutinizing and deducting from the details of reality in order to pursue something that we can’t see directly but can follow the traces of. In the awareness that we can always be wrong, and therefore ready at any moment to change direction if a new track appears; but knowing also that if we are good enough we will get it right and will find what we are seeking. This is the nature of science.”
The heat of black holes is like the Rosetta Stone of physics, written in a combination of three languages – Quantum, Gravitational and Thermodynamic – still awaiting decipherment in order to reveal the true nature of time.
We belong to a short-lived genus of species. All of our cousins are already extinct. What's more, we do damage. The brutal climate and environmental changes which we have triggered are unlikely to spare us. For the Earth they may turn out to be a small irrelevant blip, but I do not think that we will outlast them unscathed – especially since public and political opinion prefers to ignore the dangers which we are running, hiding our heads in the sand. We are perhaps the only species on Earth to be conscious of the inevitability of our individual mortality. I fear that soon we shall also have to become the only species that will knowingly watch the coming of its own collective demise, or at least the demise of its civilization.
Ma c'è di peggio: questi salti con cui ogni oggeto passa a un'interazione all'altra non avvengono in modo previsibile, ma largamente a caso. Non è possibile prevedere dove en elettrone comparirà di nuovo, ma solo calcolere la probabilità che appaia qui o lì. La probabilità fa capolino nel cuore della fisica, là dove sembrava tutto fosse regolato da leggi precise, univoche e inderogabile.I certainly don't understand everything, but quite a lot. Let me see...
But this is ?the point?: these jumps with which each object passes from one interaction to another do not happen in a predictable way, but largely by chance. It is not possible to predict where an electron will ?turn up? again, but only calculate the probability that it appears here or there. Probability makes ?? in the heart of physics, there where it seemed all was regulated by laws precise, unequivocal and unbreakable.Well, I seem to be making progress. I think I will reread the book, and see if R can fill more holes in my still extremely uncertain vocabulary...
In short, the theory describes a colourful and amazing world where universes explode, space collapses into bottomless holes, time sags and slows near a planet, and the unbounded extensions of interstellar space ripple and sway like the surface of the sea… And all this, which emerged gradually from my mice-gnawed book, was not a tale told by an idiot in a fit of lunacy, or a hallucination caused by Calabria’s burning Mediterranean sun and its dazzling sea. It’s real.
Or better, a glimpse of reality, a little less veiled than our blurred and banal everyday view of it. A reality which seems to be made of the same stuff which our dreams are made of, but which is nevertheless more real than our clouded quotidian dreaming.
Nature is our home, and in nature we are at home. This strange, multicoloured and astonishing world which we explore – where space is granular, time does not exist, and things are nowhere – is not something that estranges us from our true selves, for this is only what our natural curiosity reveals to us about the place of our dwelling. About the stuff of which we ourselves are made. We are made of the same stardust of which all things are made, and when we are immersed in suffering or when we are experiencing intense joy we are being nothing other than what we can’t help but be: a part of our world.