Rovelli Quotes

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.

In his youth Albert Einstein spent a year loafing aimlessly. You don't get anywhere by not 'wasting' time- something, unfortunately, that the parents of teenagers tend frequently to forget.

Genius hesitates.

Here, on the edge of what we know, in contact with the ocean of the unknown, shines the mystery and beauty of the world. And it’s breathtaking.

This is time for us. Memory. A nostalgia. The pain of absence. But it isn't absence that causes sorrow. It is affection and love. Without affection, without love, such absences would cause us no pain. For this reason, even the pain caused by absence is in the end something good and even beautiful. Because it feeds on that which gives meaning to life.

The very foundation of science is to keep the door open to doubt.

Because everything that begins must end. What causes us to suffer is not in the past or the future: it is here, now, in our memory, in our expectations. We long for timelessness, we endure the passing of time: we suffer time. Time is suffering.

The atoms of our body, as well, flow in and away from us. We, like waves and like all objects, are a flux of events; we are processes, for a brief time monotonous

We are stories, contained within the twenty complicated centimeters behind our eyes...

We are made up of the same atoms and the same light signals as are exchanged between pine trees in the mountains and stars in the galaxies.

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.

We understand the world in its becoming, not in its being.

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.

It is like the point where the rainbow touches the forest. We think that we can see it—but if we go to look for it, it isn’t there.

It is hardly surprising that there are more things in heaven and earth, dear reader, than have been dreamed of in our philosophy - or in our physics.

The ability to understand something before it’s observed is at the heart of scientific thinking.

Once again, the world seems to be less about objects than about interactive relationships.

You don’t get to new places by following established tracks.

What are we, in this boundless and glowing world?

If I ask whether two events—one on Earth and the other on Proxima b—are happening “at the same moment,” the correct answer would be: “It’s a question that doesn’t make sense, because there is no such thing as ‘the same moment’ definable in the universe.” The “present of the universe” is meaningless.

What opens our minds and shows the limits of our ideas is an encounter with other people, other cultures, other ideas.

We are all in the depths of a cave, chained by our ignorance, by our prejudices, and our weak senses reveal to us only shadows. If we try to see further, we are confused; we are unaccustomed. But we try. This is science. Scientific

We not only learn, but we also learn to gradually change our conceptual framework and to adapt it to what we learn.

There is a feeling of deep universalism, in the wake of the splendid words of Democritus: “To a wise man, the whole earth is open, because the true country of a virtuous soul is the entire universe.

All of the sons of Adam are part of one single body, They are of the same essence. When time afflicts us with pain In one part of that body All the other parts feel it too. If you fail to feel the pain of others You do not deserve the name of man.

Quantum mechanics and experiments with particles have taught us that the world is a continuous, restless swarming of things, a continuous coming to light and disappearance of ephemeral entities. A set of vibrations, as in the switched-on hippie world of the 1960s. A world of happenings, not of things. The

There are frontiers where we are learning, and our desire for knowledge burns. They are in the most minute reaches of the fabric of space, at the origins of the cosmos, in the nature of time, in the phenomenon of black holes, and in the workings of our own thought processes. 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.

Quantum mechanics extends this relativity in a radical way: all variable aspects of an object exist only in relation to other objects. It is only in interactions that nature draws the world.

When Einstein died, his greatest rival, Bohr, found for him words of moving admiration. When a few years later Bohr in turn died, someone took a photograph of the blackboard in his study. There’s a drawing on it. A drawing of the ‘light-filled box’ in Einstein’s thought experiment. To the very last, the desire to challenge oneself and understand more. And to the very last: doubt

I am my mother’s caresses, and the serene kindness with which my father calmly guided me; I am my adolescent travels; I am what my reading has deposited in layers in my mind; I am my loves, my moments of despair, my friendships, what I’ve written, what I’ve heard; the faces engraved on my memory. I am, above all, the one who a minute ago made a cup of tea for himself. The one who a moment ago typed the word “memory” into his computer. The one who just composed the sentence that I am now completing. If all this disappeared, would I still exist? I am this long, ongoing novel. My life consists of it.

Life is precious to us because it is ephemeral.

I believe that this example demonstrates how great science and great poetry are both visionary, and may even arrive at the same intuitions. Our culture is foolish to keep science and poetry separated: they are two tools to open our eyes to the complexity and beauty of the world.

It is entropy, not energy, that keeps stones on the ground and the world turning.

Life on Earth gives only a small taste of what can happen in the universe.

But it isn’t absence that causes sorrow. It is affection and love. Without affection, without love, such absences would cause us no pain. For this reason, even the pain caused by absence is, in the end, something good and even beautiful, because it feeds on that which gives meaning to life.

The world is complex, and we capture it with different languages, each appropriate to the process that we are describing.

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.

Human beings often cling to their certainties for fear that their opinions will be proven false. But a certainty that cannot be called into question is not a certainty. Solid certainties are those that survive questioning. In order to accept questioning as the foundation for our voyage toward knowledge, we must be humble enough to accept that today’s truth may become tomorrow’s falsehood.

To the very last, the desire to challenge oneself and understand more. And to the very last: doubt.

Before Newton, time for humanity was the way of counting how things changed. Before him, no one had thought it possible that a time independent of things could exist. Don't take your intuitions and ideas to be 'natural': they are often the products of the ideas of audacious thinkers who came before us.

To trust immediate intuitions rather than collective examination that is rational, careful, and intelligent is not wisdom: it is the presumption of an old man who refuses to believe that the great world outside his village is any different from the one that he has always known. As

we are all born from the same celestial seed; all of us have the same father, from which the earth, the mother who feeds us, receives clear drops of rain, producing from them bright wheat and lush trees, and the human race, and the species of beasts, offering up the foods with which all bodies are nourished, to lead a sweet life and generate offspring

Temporality is profoundly linked to blurring. The blurring is due to the fact that we are ignorant of the microscopic details of the world. The time of physics is, ultimately, the expression of our ignorance of the world. Time is ignorance.

The most credible answers are the ones given by science, because science IS the search for the most credible answers available, not for answers pretending to certainty.

Things change only in relation to one another. At a fundamental level, there is no time.

I believe that we need to adapt our philosophy to our science, and not our science to our philosophy.

All things are continually interacting with each other, and in doing so each bears the traces of that with which it has interacted: and in this sense all things continuously exchange information about each other.

Compare ‘now’ with ‘here’. ‘Here’ designates the place where a speaker is: for two different people ‘here’ points to two different places. Consequently ‘here’ is a word the meaning of which depends on where it is spoken. The technical term for this kind of utterance is ‘indexical’. ‘Now’ also points to the instant in which the word is uttered and is also classed as ‘indexical’. But no one would dream of saying that things ‘here’ exist, whereas things that are not ‘here’ do not exist. So then why do we say that things that are 'now' exist and that everything else doesn't?

The incompleteness and the uncertainty of our knowledge, our precariousness, suspended over the abyss of the immensity of what we don’t know, does not render life meaningless: it makes it interesting and precious.

Quantum mechanics reveals to us that the more we look at the detail of the world, the less constant it is. The world is not made up of tiny pebbles. It is a world of vibrations, a continuous fluctuation, a microscopic swarming of fleeting microevents.

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.

We inhabit time as fish live in water. Our being is being in time.

O gentlemen, the time of life is short . . . And if we live, we live to tread on kings. Shakespeare, Henry IV, Part I (act 5, scene 2)

Past and future are different from each other. Cause precedes effect. Pain comes after a wound, not before it. The glass shatters into a thousand pieces, and the pieces do not re-form into a glass. We cannot change the past; we can have regrets, remorse, memories. The future instead is uncertainty, desire, anxiety, open space, destiny, perhaps. We can live toward it, shape it, because it does not yet exist. Everything is still possible... Time is not a line with two equal directions: it is an arrow with different extremities.

This is the disconcerting conclusion that emerges from Boltzmann’s work: the difference between the past and the future refers only to our own blurred vision of the world. It’s a conclusion that leaves us flabbergasted: is it really possible that a perception so vivid, basic, existential—my perception of the passage of time—depends on the fact that I cannot apprehend the world in all of its minute detail? On a kind of distortion that’s produced by myopia? Is it true that, if I could see exactly and take into consideration the actual dance of millions of molecules, then the future would be “just like” the past?

National identity is a con. It's good for overcoming local interests for the common good, but it is short-sighted and counterproductive when it promotes the interests of a totally artificial group – 'our nation' – above a more ample sense of what the common good consists of.

Here, in the vanguard, beyond the borders of knowledge, science becomes even more beautiful—incandescent in the forge of nascent ideas, of intuitions, of attempts. Of roads taken and then abandoned, of enthusiasms. In the effort to imagine what has not yet been imagined. Twenty

I believe that our species will not last long. It does not seem to be made of the stuff that has allowed the turtle, for example, to continue to exist more or less unchanged for hundreds of millions of years, for hundreds of times longer, that is, than we have even been in existence. 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 that we have triggered are unlikely to spare us.

As human beings, we live by emotions and thoughts. We exchange them when we are in the same place at the same time, talking to each other, looking into each other's eyes, brushing against each other's skin. We are nourished by this network of encounters and exchanges. But, in reality, we do not need to be in the same place and time to have such exchanges. Thoughts and emotions that create bonds of attachment between us have no difficulty in crossing seas and decades, sometimes even centuries, tied to thin sheets of paper or dancing between the microchips of a computer. We are part of a network that goes far beyond the few days of our lives and the few square meters that we tread. This book is also a part of that weave...

We can think of the world as made up of things. Of substances. Of entities. Of something that is. Or we can think of it as made up of events. Of happenings. Of processes. Of something that occurs. Something that does not last, and that undergoes continual transformation, that is not permanent in time.

Science is a continual exploration of ways of thinking. Its strength is its visionary capacity to demolish preconceived ideas, to reveal new regions of reality, and to construct new and more effective images of the world. This adventure rests upon the entirety of past knowledge, but at its heart is change.

che significa che siamo liberi di prendere delle decisioni, se il nostro comportamento non fa che seguire le leggi della natura?

How long is forever?” asks Alice. “Sometimes, just one second,” replies the White Rabbit. There are dreams lasting an instant in which everything seems frozen for an eternity.

Those who criticize the usefulness of philosophy for science, Aristotle has noticed, are not doing science: they are doing philosophy.

In quantum mechanics no object has a definite position, except when colliding headlong with something else.

Science is about reading the world from a gradually widening point of view.

The world, particles, light, energy, space, and time—all of this is nothing but the manifestation of a single type of entity: covariant quantum fields.

It is not against nature to be curious: it is our nature to be so.

if nothing else around it changes, heat cannot pass from a cold body to a hot one......This is the only basic law of physics that distinguishes the past from the future.

For everything that moves, time passes more slowly.

The world is like a collection of interrelated points of view.

Things” in themselves are only events that for a while are monotonous

I remember a little girl... But how can that be... Once I was that little Resi, and then one day I became an old woman? ...If God wills it so, why allow me to see it? Why doesn't he hide it from me? Everything is a mystery, such a deep mystery... I feel the fragility of things in time. From the bottom of my heart, I feel we should cling to nothing. Everything slips through our fingers. All that we seek to hold on to dissolves. Everything vanishes, like mist and dreams... Time is a strange thing. When we don't need it, it is nothing. Then, suddenly, there is nothing else. It is everywhere around us. Also within us. It seeps into our faces. It seeps into the mirror, runs through my temples... Between you and I it runs silently, like an hourglass. Oh, Quin Quin. Sometimes I feel it flowing inexorably. Sometimes I get up in the middle of the night and stop all the clocks...

We are stories, contained within the twenty complicated centimeters behind our eyes, lines drawn by traces left by the (re)mingling together of things in the world, and oriented toward predicting events in the future, toward the direction of increasing entropy, in a rather particular corner of this immense, chaotic universe.

The greatness of literature lies in its capacity to communicate the experiences and feelings of human beings in all their variety, affording us glimpses of the boundless vastness of humanity.

A moving object therefore experiences a shorter duration than a stationary one: a watch marks fewer seconds, a plant grows more slowly, a young man dreams less. For a moving object, time contracts.

I do not fear death. I fear suffering. And I fear old age, though less so now that I am witnessing the tranquil and pleasant old age of my father. I am afraid of frailty, and of the absence of love. But death does not alarm me. It did not scare me when I was young, and I thought at the time that this was because it was such a remote prospect. But now, at sixty, the fear has yet to arrive. I love life, but life is also struggle, suffering, pain. I think of death as akin to a well-earned rest.

In the world described by quantum mechanics there is no reality except in the relations between physical systems. It isn’t things that enter into relations but, rather, relations that ground the notion of ‘thing’. The world of quantum mechanics is not a world of objects: it is a world of events. Things are built by the happening of elementary events: as the philosopher Nelson Goodman wrote in the 1950s, in a beautiful phrase, ‘An object is a monotonous process.’ A stone is a vibration of quanta that maintains its structure for a while, just as a marine wave maintains its identity for a while before melting again into the sea.

What I see, in other words, is not a reproduction of the external world. It is what I expect, corrected by what I can grasp. The relevant input is not that which confirms what we already know, but that which contradicts our expectations.

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 - scrutinising 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. That is the nature of science.

The notion of “the present” refers to things that are close to us, not to anything that is far away. Our “present” does not extend throughout the universe. It is like a bubble around us.

I don’t like to thank God: I like to wake in the morning, look at the sea and thank the wind, the waves, the sky, the fragrance of plants, the life that allows me to exist, the sun that rises.

A university student attending lectures on general relativity i the morning and others on quantum mechanics in the afternoon might be forgiven for thinking that his professors are fools, or have neglected to communicate with each other for at least a century.

We have a hundred billion neurons in our brains, as many as there are stars in a galaxy, with an even more astronomical number of links and potential combinations through which they can interact. We are not conscious of all of this. “We” are the process formed by this entire intricacy, not just by the little of it of which we are conscious.

To hear a cultivated person of today joking almost boastfully that they are completely ignorant about science is as depressing as hearing a scientist bragging that they have never read a poem. Poetry and science are both manifestations of the spirit that creates new ways of thinking the world, in order to understand it better. Great science and great poetry are both visionary, and sometimes may arrive at the same insights. The culture of today that keeps science and poetry so far apart is essentially foolish, to my way of thinking, because it makes us less able to see the complexity and the beauty of the world as revealed by both.

A precious miracle that the infinite play of combinations has unlocked for us, allowing us to exist. We may smile now. We can go back to serenely immersing ourselves in time - in our finite time - to savoring the clear intensity of every fleeting and cherished moment of the brief circle of our existence.

A stone is a prototypical “thing”: we can ask ourselves where it will be tomorrow. Conversely, a kiss is an “event.” It makes no sense to ask where the kiss will be tomorrow. The world is made up of networks of kisses, not of stones.

Science is born from this act of humility: not trusting blindly in our past knowledge and our intuition. Not believing what everyone says. Not having faith in the accumulated knowledge of our fathers and grandfathers. We learn nothing if we think that we already know the essentials, if we assume that they were written in a book or known by the elders of the tribe. The centuries in which people had faith in what they believed were the centuries in which little new was learned.

If things fall, it is due to this slowing down of time. Where time passes uniformly, in interplanetary space, things do not fall. They float, without falling. Here on the surface of our planet, on the other hand, the movement of things inclines naturally toward where time passes more slowly, as when we run down the beach into the sea and the resistance of the water on our legs makes us fall headfirst into the waves. Things fall downward because, down there, time is slowed by the Earth.

Being aware that we may be wrong is different from claiming that it is senseless to speak of right and wrong. Recognizing diversity and taking seriously ideas that diverge from our own is different from claiming that all ideas are equally worthy. Knowing that a given judgment is born within a complex cultural context and is related to many others does not necessarily imply that we are unable to recognize it is wrong.

Those who defend this way of thinking about reality—eternalism—frequently cite Einstein, who in a famous letter writes: For people like us who believe in physics the distinction between past, present and future is only a stubbornly persistent illusion.

An elementary structure of the world is emerging, generated by a swarm of quantum events, where time and space do not exist. Quantum fields draw together space, time, matter, and light, exchanging information between one event and another. Reality is a network of granular events; the dynamic that connects them is probabilistic; between one event and another, space, time, matter, and energy melt into a cloud of probability.

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.” A

None of the pieces that time has lost (singularity, direction, independence, the present, continuity) puts into question the fact that the world is a network of events. On the one hand, there was time, with its many determinations; on the other, the simple fact that nothing is: things happen.

Le equazioni della meccanica quantistica e le loro conseguenze vengono usate quotidianamente da fisici, ingegneri, chimici e biologi, nei campi più svariati. Sono utilissime per tutta la tecnologia contemporanea. Non ci sarebbero i transistor senza la meccanica quantistica. Eppure restano misteriose: non descrivono cosa succede a un sistema fisico, ma solo come un sistema fisico viene percepito da un altro sistema fisico. Che significa? Significa che la realtà essenziale di un sistema è indescrivibile? Significa solo che manca un pezzo alla storia? O significa, come a me sembra, che dobbiamo accettare l’idea che la realtà sia solo interazione?

This does not mean that science is just the art of making measurable predictions. Some philosophers of science overly circumscribe science by limiting it to its numerical predictions. They miss the point, because they confuse the instruments with the objectives. Verifiable quantitative predictions are instruments to validate hypotheses. The objective of scientific research is not just to arrive at predictions: it is to understand how the world functions; to construct and develop an image of the world, a conceptual structure to enable us to think about. Before being technical, science is visionary.

As human beings, we live by emotions and thoughts. We exchange them when we are in the same place at the same time, talking to each other, looking into each other’s eyes, brushing against each other’s skin. We are nourished by this network of encounters and exchanges. But, in reality, we do not need to be in the same place and time to have such exchanges. Thoughts and emotions that create bonds of attachment between us have no difficulty in crossing seas and decades, sometimes even centuries, tied to thin sheets of paper or dancing between the microchips of a computer. We are part of a network that goes far beyond the few days of our lives and the few square meters that we tread. This book is also a part of that weave. . .

Every moment of our existence is linked by a peculiar triple thread to our past—the most recent and the most distant—by memory. Our present swarms with traces of our past. We are histories of ourselves, narratives. I am not this momentary mass of flesh reclined on the sofa typing the letter a on my laptop; I am my thoughts full of the traces of the phrases that I am writing; I am my mother’s caresses, and the serene kindness with which my father calmly guided me; I am my adolescent travels; I am what my reading has deposited in layers in my mind; I am my loves, my moments of despair, my friendships, what I’ve written, what I’ve heard; the faces engraved on my memory. I am, above all, the one who a minute ago made a cup of tea for himself. The one who a moment ago typed the word “memory” into his computer. The one who just composed the sentence that I am now completing. If all this disappeared, would I still exist? I am this long, ongoing novel. My life consists of it.

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 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 that 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.

If I look at a forest from afar, I see a dark green velvet. As I move toward it, the velvet breaks up into trunks, branches and leaves: the bark of the trunks, the moss, the insects, the teeming complexity. In every eye of every ladybug, there is an extremely elaborate structure of cells connected to neurons that guide and enable them to live. Every cell is a city, every protein a castle of atoms; in each atomic nucleus an inferno of quantum dynamics is stirring, quarks and gluons swirl, excitations of quantum fields. This is only a small wood on a small planet that revolves around a little star, among one hundred billion stars in one of the thousand billion galaxies constellated with dazzling cosmic events. In every corner of the universe we find vertiginous wells of layers of reality.