# Brian Greene

Brian Greene (born February 9, 1963) is a theoretical physicist and string theorist. He has become known to a wider audience through his books for the general public, The Elegant Universe, Icarus at the Edge of Time and The Fabric of the Cosmos, and a related PBS television special.

## Quotes

* Physicists describe the two properties of physical laws—that they do not depend on when or where you use them—as symmetries of nature. By this usage physicists mean that nature treats every moment in time and every location in space identically—symmetrically—by ensuring that the same fundamental laws are in operation. Much in the same manner that they affect art and music, such symmetries are deeply satisfying; they highlight an order and coherence in the workings of nature. The elegance of rich, complex, and diverse phenomena emerging from a simple set of universal laws is at least part of what physicists mean when they invoke the term "beautiful."
** The Elegant Universe (1999) Ch. 7 The "Super" in Superstrings.
* Physicists are more like avant-garde composers, willing to bend traditional rules and brush the edge of acceptability in the search for solutions. Mathematicians are more like classical composers, typically working within a much tighter framework, reluctant to go to the next step until all previous ones have been established with due rigor. Each approach has its advantages as well as drawbacks; each provides a unique outlet for creative discovery. Like modern and classical music, it’s not that one approach is right and the other wrong – the methods one chooses to use are largely a matter of taste and training.
** The Elegant Universe : Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory (1999), p. 271
* The real question is whether all your pondering and analyses will convince you that life is worth living. That's what it all comes down to.
** The Fabric of the Cosmos : Space, Time, and the Texture of Reality (2004), p. 3
* Superstring theory starts off by proposing a new answer to an old question: what are the smallest, indivisible constituents of matter? For many decades, the conventional answer has been that matter is composed of particles... that can be modeled as dots that are indivisible and that have no size and no internal structure. Conventional theory claims, and experiments confirm, that these particles combine in various ways to produce protons, neutrons, and a wide variety of atoms and molecules... Superstring theory tells a different story. ...it does claim that these particles are not dots. Instead... every particle is composed of a tiny filament of energy, some hundred billion billion times smaller than a single atomic nucleus, which is shaped like a string. And just as a violin string can vibrate in different patterns, each of which produces a different musical tone, the filaments of superstring theory can also vibrate in different patterns. But these vibrations... produce different particle properties. ...All species of particles are unified in superstring theory since each arises from a different vibrational pattern executed by the same underlying entity.
** The Fabric of the Cosmos : Space, Time, and the Texture of Reality (2004), p. 17
* Well, a big question is how did the universe begin. And we, cannot answer that question. Some people think that the big bang is an explanation of how the universe began, its not. The big bang is a theory of how the universe evolved from a split second after whatever brought it into existence. And the reason why we’ve been unable to look right back at time zero, to figure out how it really began; is that conflict between Einstein’s ideas of gravity and the laws of quantum physics. So, string theory may be able to — it hasn’t yet; we’re working on it today — feverishly. It may be able to answer the question, how did the universe begin. And I don’t know how it’ll affect your everyday life, but to me, if we really had a sense of how the universe really began, I think that would, really, alert us to our place in the cosmos in a deep way.
** In response to David Letterman's question, "What do we now know [about the universe] we didn’t know before?" on The Late Show (23 March 2005)
* ... the extra dimensions have to be curled up into this so-called Calabi-Yau shape, or Calabi-Yau manifold ... it's a manifold that is as close as you can be to being flat without literally being a flat shape ... In six dimensions you can have something that is known as Ricci-flat ...
** (November 20, 2023)"Brian Greene: The Truth About String Theory, Eric Weinstein, & TOEs (369)". Dr Brian Keating. (quote at 38:40 of 1:42:01 in video)

## Quotes about Greene

* ... I knew a guy, Brian Greene. I helped him to get a summer job at IBM because people told me he was brilliant, and he was. And when I heard that he had gotten a professorship at Columbia, it was described to me like this. It was a joint professorship between the physics and the math department, because the math department thought what he was doing was physics, and the physics department thought that what he was doing was math.
** Gregory Chaitin, "The Rise and Fall of Academia". Theories of Everything with Curt Jaimungal, YouTube. (quote at 6:04 in video)
* The Fabric of the Cosmos covers a wider field than The Elegant Universe and paints it with a broader brush. There is not much overlap between the two books. ...Neither is a prerequisite for reading the other. The new book is easier, and should preferably be read first. Readers who get stuck halfway through The Elegant Universe may find the new book more digestible.
** Freeman Dyson, The Scientist As Rebel (2006)
* Greene takes it for granted, and here the great majority of physicists agree with him, that the division of physics into separate theories for large and small objects is unacceptable. ...Greene believes that there is an urgent need to find a theory of quantum gravity that applies to large and small objects alike. ...As a conservative, I do not agree that a division of physics into separate theories for large and small is unacceptable. ...The essence of any theory of quantum gravity is that there exists a particle called the graviton... I looked at various possible ways of detecting gravitons and did not find a single one that worked. Because of the extreme weakness of the gravitational interaction, any putative detector of gravitons has to be extremely massive. If the detector has normal density, most of it is too far from the source of gravitons to be effective, and if it is compressed to a high density around the source it collapses into a black hole. There seems to be a conspiracy of nature to prevent the detector from working.
** Freeman Dyson, The Scientist As Rebel (2006)
* He introduced a whole new set of physicists to join the pantheon that includes Einstein, Ernest Rutherford, Niels Bohr, Werner Heisenberg, Erwin Schrödinger, Wolfgang Pauli, James Chadwick, Roger Penrose, and Stephen Hawking. Among these new names Edward Witten stands out, together with Eugenio Calabi, Theodor Kaluza, Andrew Strominger, Stein Stømme, Cumrun Vafa, Gabriele Veneziano, and Shing-Tung Yau, about as international a group of names as you could find anywhere.
** Peter Watson (17 October 2013). Terrible Beauty: A Cultural History of the Twentieth Century: The People and Ideas that Shaped the Modern Mind: A History. Orion. p. 872. ISBN 978-1-78022-673-6.