In A Flight of Starlings

By Giorgio Parisi (Penguin, 2023).

Preface

• how can scientists promote the trust in science?

  Show our work: demonstrate in an engaging way how scientists toil, doubt, succeed, and fail.

  Our job as scientists is to illuminate for everyone the truths that we discover.

Chapter 1: In a flight of starlings

• aim right:

  The fact that no one else has succeeded is scarcely off-putting. This, after all, is the scientist’s calling: to imagine or to do what no one has done before.

  Before beginning, it is crucial to understand whether or not we have the competence, technical skills, and tools that will allow us to accomplish the job.

  if the target is so high that we have no chance of reaching it, then it’s better not to begin.

• the wonders of complex system:

  understand quantitatively how collective behavior emerges from simple rules governing the interaction between individual actors.

• Philip Warren Anderson: 1972 article “More Is Different”, maintaining that an increase in the number of components in a system creates a change that is not just quantitative but qualitative.

• understand the relationship between microscopic rules and macroscopic behavior.

• project:

  designing the experiment, collecting and analyzing data, developing computer modeling for simulations, and interpreting the experimental results.

• which methodologies are scientific and relevant and which should be rejected as incapable of answering the real questions posed by the discipline.

• Max Planck: A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

Chapter 2: Physics in Rome, around fifty years ago

• voting:

  as well as the responsibility of those who by voting “no” had conferred legitimacy on the process.

• ideas are often like boomerangs:

  Interesting and unusual results can turn out to apply to totally unexpected fields.

Chapter 3: Je ne regrette rien

• blindness:

  Researchers often pass by great discoveries without being able to grasp them. You need great intuition to navigate infinite possibilities, and sometimes intuition fails.

Chapter 4: Phase transitions, or collective phenomena

• Tini Veltman: Don’t do too many things—concentrate on a few important ones.

  precisely by studying many things at once that I was able to make connections between different fields—the basis of many of my later discoveries.

Chapter 5: Spin glasses: the introduction of disorder

• importance of model simplification:

  Galileo Galilei who found one of the most powerful tools for investigating nature: simplifying phenomena.

Chapter 6: Metaphors in science

• the difference between a good mathematician and a bad one is that a good mathematician understands immediately which mathematical statements are true and which are false, whereas a bad mathematician has to try to prove them in order to know which are true and which are false.

• Bohr apparently replied: “Einstein, stop telling God what to do or not do.”

• Physics and math:

  Physics can be considered a kind of applied math. It starts with a concrete problem and translates it into the language of physics. … The physicist sometimes uses mathematics ungrammatically; not following all the rules of grammar is a license that we grant to poets.

• Bettrand Russell put it, “Mathematics may be defined as the subject in which we never know what we are talking about.”

• A physicist translates concrete phenomena into a mathematical language where many of their material characteristics are lost, leaving just those essential for studying the phenomena.

• when the same formal mathematical system has two completely different physical manifestations, you can use physics insights from both systems to obtain valuable complementary information.

• shared correspondence with the same mathematical structure.

Chapter 7: How ideas are born

• open-mindedness:

  the danger that our thinking could become too fixed to the point of hindering new ideas.

• formulating our ideas clearly and precisely, which often cannot be done without revisiting what we took for granted.

• unconscious thinking:

  Pausing one’s concentration on a difficult problem—to allow ideas to settle, and to face that problem again with a fresh mind—is no doubt very common.

• the moment the word comes to mind, we already know the next word and probably the whole sentence as well. But if so, the whole sentence must be present in our mind in nonverbal form before it is expressed in words.

• intuition:

  You have to get to know your experimental setup so well, the system that you are measuring, the phenomena that you are observing, to be in a position to give the right answer without even thinking. If they ask you a question (or you ask it), you must be in a position to give the right answer immediately and then afterward, on reflection, to be able to say why it is right.

• good students must reflect on a theorem until the theorem seems obvious and the proof, consequently, seems superfluous.

• when writing a novel Luce d’Eramo often proceeded by rereading everything she had written so far, and only when did she decide how to begin the next scene.

• in practice we seek arguments to demonstrate the truth of the proposal, and if we do not succeed we try to prove its falsity, oscillating between the two without getting much further forward.

  The simple information that the property was demonstrable was enough for him to arrive at the long-sought-after proof for himself in less than ten seconds. … sometimes a minimal amount of information is enough to cause substantial progress in a field to which much thought has been given.

• Several days later, Einstein remarked to a neighbor: “Who knows what the poor housepainter must have been thinking as he fell,” and his neighbor replied: “I spoke to him, and he said that as he fell he did not feel as if he was still on the chair, almost as if there was no force of gravity.”

• There are many who have had the right intuition but have then been unable to bring it to fruition.

Chapter 8: The meaning of science

• Science is like sex: sometimes something useful comes out, but that is not the reason we are doing it. — Richard Feynman (allegedly)

• being paid to do what we are so passionate about:

  Being a physicist is hard, but it’s better than having to work for a living. — Aurelio Grillo

• the Lincean Academy in 1603, the Royal Society in 1660, the French Academy of Sciences in 1666, the American Philosophical Society in 1743, founded by Benjamin Franklin with the explicit purpose of promoting useful knowledge.

• pure science not only provides applied science with the knowledge it needs to develop—languages, metaphors, conceptual frameworks—but also has a more hidden if no less important role to play. In fact, basic scientific activities work like a gigantic proving ground for technological products, and for simulating the consumption of high-tech goods.

• popular distrust of science is partly the result of a certain perceived arrogance in scientists:

  This refusal to accept and acknowledge their own limitations can undermine the prestige of scientists who display an excessive, disingenuous confidence to a public that has a perception of the partiality and limits of their views. … In the face of a science perceived as inaccessible magic, nonscientists are pushed toward irrational beliefs. If science comes across as pseudo-magic, then why not opt for actual magic instead?

• Science needs to be defended not just for its practical aspects but for its cultural value.

  Its value lies in the love of culture: it is like painting, sculpture, poetry, and like all of those activities of which Americans are patriotically proud, it does not serve to defend our country but makes our country worth defending. — Robert Wilson

• importance of promoting science and making it more accessible:

  It is not easy, but it is possible. We need to promote initiatives that allow people to approach modern science. If we don’t do this, scientists themselves will not be able to escape responsibility for the consequences.

To Read

• Wilson, K. G. (1971). Renormalization Group and Critical Phenomena. I. Renormalization Group and the Kadanoff Scaling Picture. Physical Review B. 4(9): 3174–3183.
• Wilson, K. G. (1971). Renormalization Group and Critical Phenomena. II. Phase-Space Cell Analysis of Critical Behavior. Physical Review B. 4(9): 3184–3205.
• Wilson, K. G. (1971). Renormalization Group and Strong Interactions. Physical Review D. 3(8): 1818–1846.
• Wilson, K. G. (1972). Feynman-Graph Expansion for Critical Exponents. Physical Review Letters. 28(9): 548–551.
• Wilson, K. G. (1983). The renormalization group and critical phenomena. Reviews of Modern Physics. 55(3): 583–600.
• Sherrington, David and Scott Kirkpatrick (1975). Solvable Model of a Spin-Glass. Physical Review Letters. 35(26): 1792–1796.
• Parisi, Giorgio (1979). Toward a mean field theory for spin glasses. Physics Letters A. 73(3): 203–205.
• Parisi, Giorgio (1979). Infinite Number of Order Parameters for Spin-Glasses. Physical Review Letters. 43(23): 1754–1756.
• Marinari, E. and G. Parisi (1992). Simulated Tempering: A New Monte Carlo Scheme. Europhysics Letters. 19(6): 451–458.
• Mézard, M., G. Parisi, N. Sourlas, G. Toulouse and M. Virasoro (1984). Nature of the spin-glass phase. Physical Review Letters. 52(13): 1156–1159.
• Mézard, M., G. Parisi and M. Virasoro (1987). Spin glass theory and beyond: An Introduction to the Replica Method and Its Applications. World Scientific.
• Mézard, M., G. Parisi and R. Zecchina (2002). Analytic and Algorithmic Solution of Random Satisfiability. Science. 297(5582): 812–815.
• Talagrand, Michel (2011). Mean Field Models for Spin Glasses Volume I: Basic Examples. Springer.
• Talagrand, Michel (2011). Mean Field Models for Spin Glasses Volume II: Advanced Replica-Symmetry and Low Temperature. Springer.