Quotes from Carlo Rovelli

A calculation, in fact, demonstrates that without nodes, physical space has no volume. In other words, it is in the nodes of the graph, not in the lines, that the volume of space "resides." The lines "link together" individual volumes sitting at the nodes.

a star must ignite for hydrogen to begin to burn there into helium. What causes stars to ignite? Another process that increases entropy: the contraction due to gravity of one of the large clouds of hydrogen that sail throughout the galaxy.

Let's begin with a simple fact: time passes faster in the mountains than it does at sea level.

Büyük bir y?ld?z tüm yak?t?n? (hidrojeni) tüketti?inde sönmeye ba?lar. Geriye kalanlar, yanmadan kaynaklanan ?s?yla ayakta kalamaz, kendi a??rl???yla çöker, uzay? o kadar güçlü bir biçimde e?er ki gerçek bir deli?e dü?er. Bunlar ünlü karadeliklerdir.

Nuestro saber es demasiado débil para no aceptar vivir en el misterio. Y precisamente porque el misterio existe, y porque es tan profundo, no podemos confiar en quien declara poseer la llave de este misterio. Aceptar la incertidumbre y la novedad de un pensamiento que busca nuevos caminos conlleva nuevos riesgos.

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. For

Any description of a system is therefore always a description of the information a system has about another system, that is to say, the correlation between the two systems.

We are perhaps the only species on Earth to be conscious of the inevitability of our individual mortality.

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.

Richard Feynman, who more than anyone has known how to juggle with the theory, has written: "I think I can state that nobody really understands quantum mechanics.

What are the elementary "atoms" that vibrate, making a black hole hot? Hawking left this problem unanswered. Loop theory provides a possible answer. The elementary "atoms" of a black hole that vibrate, responsible for its temperature, are the individual quanta of space on its surface.

I want a theory of physics that accounts for the structure of the universe, that clarifies what it is to be an observer in the universe, not a theory that makes the universe depend on me observing it.

Aristotle is the first we are aware of to have asked himself the question "What is time?," and he came to the following conclusion: time is the measurement of change.

The discovery of quantum theory, I believe, is the discovery that the properties of any entity are nothing other than the way in which that entity influences others. It exists only through its interactions. Quantum theory is the theory of how things influence each other. And this is the best description of nature that we have.54

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.

Fearing the transition, being afraid of death, is like being afraid of reality itself; like being afraid of the sun. Whatever for?

Every cubic centimeter of space, and every second that passes, is the result of this dancing foam of extremely small quanta.

Hold on tight, because we are about to take off. "NOW" MEANS NOTHING What is happening "now" in a distant place? Imagine, for example, that your sister has gone to Proxima b, the recently discovered planet that orbits a star at approximately four light-years' distance from us. What is your sister doing now on Proxima b? The only correct answer is that the question makes no sense. It is like asking "What is here, in Beijing?" when we are in Venice.

Time passes more slowly for the one who keeps moving.

Is the daily spectacle of a revolving universe "illusory"? No, it is real, but it doesn't involve the cosmos alone. It involves our relation with the sun and the stars. We understand it by asking ourselves how we move. Cosmic movement emerges from the relation between the cosmos and ourselves.

Scientists are not immune from talking nonsense.

Our fear of death seems to me to be an error of evolution.

Music can occur only in time, but if we are always in the present moment, how is it possible to hear it? It is possible, Augustine observes, because our consciousness is based on memory and on anticipation.

There is no "truer" time; there are two times and they change relative to each other. Neither is truer than the other. But there are not just two times. Times are legion: a different one for every point in space. There is not one single time; there is a vast multitude of them.