"Carlo Rovelli"の名言

Time is information we don't have. Time is our ignorance.

[T]he elementary form of the mechanics of the world...does not need to mention 'time.' The world without a time variable is not a complicated one. It's a net of interconnected events, where the variables in play adhere to probabilistic rules that, incredibly, we know for a good part how to write. And it's a clear world, windswept and full of beauty as the crests of mountains; aridly beautiful as the cracked lips of the adolescent you loved.

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.

The entropy of the world in the far past appears very low to us. But this might not reflect the exact state of the world: it might regard the subset of the world' s variables with which we, as physical systems, have interacted. It is with respect to the dramatic blurring produced by our interactions with the world, caused by the small set of macroscopic variables in terms of which we describe the world, that the entropy of the universe was low.

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.

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.

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 absolute faith in the accumulated knowledge of our fathers and grandfathers. We learn nothing if we think 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. Had they trusted the knowledge of their fathers, Einstein, Newton, and Copernicus would never have called things into question and would never have been able to move our knowledge forward (259, trsl. Carnell & Segre)

We think that our minds are all powerful but in reality they’ve evolved to do what we need to do, like hunt, eat and talk to one another. So the concepts in our head are designed to deal with animals, trees, rivers and people. There’s no reason why they should be able to deal with atoms or galaxies. But I believe we’re flexible and our minds are curious, so we can change our thinking.

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

That which seems intuitive to us now is the result of scientific and philosophical elaborations in the past.

In short, [Einstein's General Theory of Relativity] describes a colorful 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 of this...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 was reality. Or better, a glimpse of reality, a little less veiled than our blurred and banal everyday view of it. A reality that seems to be made of the same stuff that our dreams are made of, but that is nevertheless more real than our clouded, quotidian dreaming.

The speed of an object is not a property of the object alone: it is a property of the object in relation to another object. The speed of a child on a moving train has a value relative to the train (a few steps per second) and a different value relative to the ground (a hundred kilometers per hour). If his mother tells the child to 'Keep still!', she does not mean that they have to throw themselves out of the window to stop in relation to the ground. She means that the child should stop with regard to the train.

Our moral values, our emotions, our loves are no less real for being part of nature, for being shared with the animal world, or fore being determined by the evolution that our species has undergone over millions of years. Rather, they are more valuable as a result of this: they are real.

But what we see and understand of the universe is not an infinity to drown in. It is a wide sea, but a finite one.

We are a species which is naturally moved by curiosity, the only one left of a group of species (the genus Homo) made up of a dozen equally curious species. The other species in the group have already become extinct; some, like the Neanderthals, quite recently, roughly thirty thousand years ago. It is group of species which evolved in Africa, akin to the hierarchical and quarrelsome chimpanzees -- and even more closely akin to the bonobos, the small, peaceful, cheerfully egalitarian and promiscuous type of chimps. A group of species which repeatedly went out of Africa in order to explore new worlds, and went far: as far, eventually, as Patagonia -- and as far, eventually, as the moon. It is not against our nature to be curious: it is in our nature to be so.

Our moral values, our emotions, our loves are no less real for being part of nature, for being shared with the animal world, or for being determined by the evolution which our species has undergone over millions of years. Rather, they are more valuable as a result of this: they are real. They are the complex reality of which we are made. Our reality is tears and laughter, gratitude and altruism, loyalty and betrayal, the past which haunts us and serenity.

Undistracted by schooling, one studies best during vacations