Category Archives: Science

To Explain the World by Steven Weinberg

To Explain the World, by Steven Weinberg, is a history of science. As he states at the very beginning, it isn’t necessarily to track our progress in science, though that naturally comes along for the ride, but rather “how we came to learn how to learn about the world.” He isn’t interested in how well the ancient Greeks did in their efforts to understand the world so much as how they did as scientists. Did they apply a scientific method? Did they perform tests of their ideas to try to validate them? Did they leave the realm of pure hypothesizing and look for real world implications of their ideas? Weinberg concludes that, for the most part, no, the Greeks weren’t much of scientists.

This is a different and often-times refreshing look at the history of science. By focusing less on what was learned and more on how it was learned, Weinberg takes us on a journey of what it means to do science. How has science, in a broader sense, evolved? How have we used it to understand the world around us?

Along the way, there are lots of examples of scientific discovery and how we did learn specific things about the universe. While Weinberg’s intention is that one doesn’t need much math to follow, the truth is that many of these concepts are rather challenging and require some time to think about them (more than I often devoted to them). Particularly when considering some of the ideas of the ancients, in which they built complex and clumsy scaffolds to support hypotheses that, for example, the Earth was the center of the universe, the more complex the model, the harder it is to get one’s head around it. He does provide an appendix of sort that goes into some of these in more detail, but unless one has pencil and paper at hand to work through them in detail, even these are less than intuitive.

However, this does bring me to one of the coolest experiences with this book. In one of the appendices, he describes a proof for Thales’ Theorem, which says that if we have a circle and a diameter, and we create a triangle from any point on the circle and the intersections of the diameter with the circle, the triangle is a right triangle. I described this proof to my daughter and she got so excited when she understood and was able to reproduce the proof. She genuinely loved the idea of being able to prove something like that.

So, there is a lot of love of science and the joy of discovery in this book. As the human race learned more about the universe around them, they also learned how to learn, to, essentially, do science. Weinberg describes this journey as a stern parent might, critiquing how far away those ancients (and not so ancients) were from true science, how they were so close but missed a key element. He isn’t criticizing, per se, but rather evaluating whether we should truly call what they were doing science.

He has a number of interesting observations about the scientific endeavor that he makes along the way, most of which I agree with:

  • “Inspiration and aesthetic judgment are important in the development of scientific theories, but the verification of these theories relies finally on impartial experimental tests of their predictions.”
  • “The progress of science has been largely a matter of discovering what questions should be asked.”
  • “Nothing about the practice of modern science is obvious to someone who has never seen it done.”
  • “Science is now international, perhaps the most international aspect of our civilization.”
  • “Science and technology benefit each other, but at its most fundamental level science is not undertaken for any practical reason.”

These last two, in particular, resonate strongly with me. We do science for science’s sake, to learn, to push the boundaries of knowledge. Some of that science may turn into useful technology, but that might not happen for decades or longer. And science is the one view of the world that has become international, embraced by parts of pretty much every culture and society in the world. It is a way of discovering knowledge that can truly be called universal.

Weinberg goes pretty deep into various aspect of Greek and Arabic knowledge, more than I want to capture here. (He does make an interesting reference to the Arab’s contribution to science: “For while in the East al-Rashid and al-Mamun were delving into Greek and Persian philosophy, their contemporaries in the West, Charlemagne and his lords, were dabbling in the art of writing their names.”) Again, the goal is to put that knowledge into context, to show how scientific their approaches to generating that knowledge was. Some of their achievements are truly amazing, and Weinberg highlights those. But, he is really interested in how they made those achievements. And, in most cases, he concludes it wasn’t really scientifically.

It wasn’t until Copernicus, Kepler, and Newton, where a predictive model of the solar system was developed based on simple laws, that what we might call modern science came to be. These scientists took observations, built models that matched them, and tested them. Galileo was an important forefather of this as he did laboratory experiments to test his ideas, not relying simply on observation of the natural world. These developments ushered in the age of science.

Overall, this was an excellent journey through the history of human learning, of the development of our abilities to do science. Along the way, there are lots of interesting tidbits of scientific (and not-so-scientific) discovery and understanding. I highly recommend it to any student of science. It provides not only context for how and why we do science, but captures that joy and spirit of discovery that drives a lot of scientific pursuit.

If Politics is in the Gut, What Does That Mean for Democracy?

In the March 2019 issue, The Atlantic published a very interesting story about the differing reactions between liberals and conservatives to “disgusting” images. Summarizing a study by Read Montague, a neuroscientist at Virginia Tech, and his colleagues, the story reports that liberals and conservatives have measurably different responses to images such as “mutilated animals, filthy toilets, and faces covered with sores.” They found that, monitoring people’s reactions via MRIs, he could predict whether they were liberal or conservative with 95% accuracy. They further found that “conservatives tend to have more pronounced bodily responses than liberals when shown stomach-churning imagery.”

This is pretty amazing, if you ask me. It suggests that, to a large extent, our political views are not shaped by reasoned thought about the issues. Rather, they are strongly determined by neurological processes that we simply don’t control. “Gut reactions” to repulsive things. Regardless of which side of the proverbial aisle one sits on, if our beliefs are so strongly connected to primal reactions, what does that mean for democracy?

Democracy relies upon reasoned debate, with the goal of reaching compromise on complex issues. No one is ever fully satisfied, but to convince the other side to go along with your point of view, you have to persuade them that you have a solid argument. Debate is all about convincing the other side of your point of view. But, if your point of view is essentially a function of your gut, what is there really to convince them of? What is there to argue about? You can create arguments to support your belief, but that is building the scaffolding after you already have the core. Rather, informed debate should be about defending beliefs that you have based on reason. We shouldn’t be defending beliefs post-facto, but develop our beliefs based on the evidence around us. If our beliefs are founded on gut reactions, we are always going the wrong way.

To me, this has profound implications for democracy. We hope, that when our politicians are working, debating, arguing, fighting for something they believe in, even if they don’t agree with you or me, that at least they have strong reasons for their beliefs and that they are working to better society based on those beliefs. But, if they really don’t have any foundation for their views beyond their gut reaction, their neurological impulses, how solid can those beliefs and the subsequent arguments be? How well can they be tied to our best interests? If they are not based on evidence or reason, can they truly be the foundation of policy?

Dark Matter by Blake Crouch

Quantum mechanics is weird. Probably the weirdest part is that it only makes predictions about the probability of what can happen. Newton’s laws say that, with a give force, an object will move this way. Quantum mechanics says that it is probable that it will move a given way, but there is a probability it will move another way. So, with quantum mechanics, we are always dealing with probability. When we measure something, one of the many choices is actually realized. But, this is at the heart of the weirdness: which one?

There are several interpretations of quantum mechanics that try to address this, but they are all, essentially, non-testable hypotheses. One is that all possibilities happen and we are living in one of those potential worlds. That is, whenever a quantum measurement is made, reality splits into different worlds, where each possibility has happened. This is the many-worlds interpretation of quantum mechanics. This splitting occurs whenever there is a measurement of a quantum system. Going even further, the many-minds interpretation says that any time a mind makes a decision, reality splits. It is this interpretation that is at the heart of Blake Crouch’s Dark Matter.

Really, the many-minds view of quantum mechanics is just the backdrop, a vehicle to let Crouch explore ideas about the road not taken. We all have wondered “what if,” what if I had asked that girl out, what if I had gotten that other job, what if that special someone was still alive? We only get one chance at life and we make the best of it. But, what if there was a chance to redo it, to take that untaken road? Crouch’s main character, Jason, had promise as a brilliant physicist. His wife, Dani, was an up and coming star artist. However, they both put those plans aside when Dani becomes pregnant, to raise their son. While both are happy, both also have regrets. What if they had made different choices?

I won’t give away the plot, as there is a lot of daring-do and action to go along with the exploration of these themes. I’ll just say that, in the end, Jason learns a few important lessons:

  • And maybe I can let go of the sting and resentment of the path not taken, because the path not taken isn’t just the inverse of who I am. It’s an infinitely branching system that represents all the permutations of my life…
  • I thought I appreciated every moment, but sitting here in the cold, I know I took it all for granted. And how could I not? Until everything topples, we have no idea what we actually have, how precariously and perfectly it all hangs together.

Dark Matter uses some out-there physics to explore some fundamental questions of existence, doing so while telling an action packed story that has some really interesting plot twists. Crouch’s approach to writing took inspiration from Michael Crichton: “I realized that he wasn’t just coming up with cool plots. He was writing books that allowed him to explore topics that interested him. Writing a thriller as self-education.” And, by educating himself, Crouch provides a yarn that is both thought-provoking and full of action.

Thirteen by Henry SF Cooper Jr

When I saw the movie Apollo 13, the one that stars Tom Hanks, I felt that the story it depicted was the embodiment of engineering to me. How a group of clever people could solve an unsolvable problem, fixing a tiny spacecraft that had malfunctioned on its way to the moon with nothing more than the parts they had on hand as they hurtled through space and the combined ingenuity of probably literally hundreds of people — 3 in that capsule and the rest on the ground. The way they systematically tackled the problem but also brought in their own out-of-the-box thinking was, for me, what engineering was all about.

(In reality, often engineering, at least at the professional scale, is not so dramatic. I almost became an engineer — this was long before the movie — but an internship at a major computer company killed that desire.)

The book Thirteen, but Henry SF Cooper Jr, recounts the Apollo 13 mission in minute detail. Cooper has scoured the logs and transcripts of the mission, interviewed many sources, and has essentially produced what feels like a step-by-step account of the mission and how they fixed the spacecraft to get it back to earth. There is no embellishments here, no extra drama. Cooper recounts what people said and, when possible, what they thought, based on their own words. He doesn’t add extra drama from what is in the record. At times, his recounting of the failure, the way everyone works to first understand and then fix what happened, and the actual return to earth, can seem a little dry. But, its factual narrative makes the actual events that much more impressive because, simply, that’s what happened.

Cooper notes multiple times that one reason that the spacecraft failed is that, simply, NASA couldn’t imagine certain things happening. As has been said about the space shuttle disasters, maybe there was some hubris, some overconfidence, in the teams. After all, they had landed multiple men on the moon by that point. They could do anything. And nothing was wrong with their designs. If anywhere, this is where Cooper lets his own biases creep in, as he clearly feels that NASA had gotten too complacent, too proud to even think of such eventualities: “they felt secure in the knowledge that the spacecraft was as safe a machine for flying to the moon as it was possible to devise. Obviously, men would not be sent into space in anything less.” At one point, he highlights how the astronauts complained about being put through simulations of such unrealistic scenarios. After the events of Apollo 13, they complained no more, at least not for a while.

The detail Cooper provides on all aspects of the mission instills a sense of wonder at how complex these missions were. To stay warm, they had to roll the spacecraft regularly to change which part faced the sun so that the electronics wouldn’t get so cold. They had to enter the atmosphere at just the right angle: too shallow, and they would bounce off; too steep and they would burn up as they approached earth. With the failing of the spacecraft, they had to figure this all out in real time again, with lots of uncertainties as to the true behavior of the ship.

Getting the astronauts home was one engineering challenge after another. Once the spacecraft failed, the very first problem they had to solve was how to keep the astronauts breathing, as their oxygen production had stopped. They also needed water but, something I learned, in space, astronauts don’t feel thirst, even when they are dehydrated, so they didn’t realize how low they were on water. The communications equipment of the lunar module, not meant to be active until they were on the moon, interfered with other devices on the spacecraft, impeding, at least initially, communications with earth. The fuel for the spacecraft was radioactive material. Normally, it would have been left on the moon. Now, they had to worry about where it would fall on the earth.

Thirteen doesn’t have the same sense of drama as a movie, but in some ways, it is all the better at conveying the impressive feats of these people as they got the spaceship home. This book won’t be for everyone, but for those with any inclination towards engineering, it provides a great sense of the drama that the profession can entail, in the right circumstances.

Boltzmann’s Atom by David Lindley

It might be hard to imagine now, but at the end of the 1800s, the scientific community was beginning to think it had more or less wrapped up all-things physics. Newton’s mechanics were well understood and Maxwell had recently shown how light behaved as a wave, giving a unified theory of electricity and magnetism. Little could they all imagine that everything would be turned on its head in just a few short years.

Presaging this transformation of physics was Ludwig Boltzmann, who was one of the leading figures of what we now call statistical mechanics. He showed how we could move beyond treating individual particles and think about them as large groups, think about their average properties. This allowed him to consider the properties of solids and liquids and gases on a scale that more directly connects with every day life. Maybe most importantly, he showed how the properties of these groups, or ensembles, of particles connected to the concept of entropy, which was a fairly vague concept before him. His impact to physics is immeasurable, and is enshrined in various concepts that bear his name, not least amongst them being the Maxwell-Boltzmann distribution and the Boltzmann factor.

However, during his life, his ideas were not so quick to catch on and were, in particular, challenged by people like Ernst Mach (yes, the one who devised the Mach scale of speed), who exposed a view that physics should only describe what is directly observed, that there was no room for theorizing what caused those observations. That, combined with Boltzmann’s relative isolation in a small university and his own near-schizophrenia with his status, led to a relatively slow acceptance of his ideas. Boltzmann’s ideas had, at their core, the concept of atoms, a concept that was not at all widely accepted during his time. As late as 1897, leading scientists such as Mach could exclaim “I don’t believe that atoms exist!”

Of course, there were theories of atoms before Boltzmann, dating back to the ancient Greeks. Lindley traces the development of our theories of atomic particles and Boltzmann’s contributions to those theories. Boltzmann’s own theoretical advances made predictions, based on the assumption of atoms, that were later validated and helped conclusively show that atoms do indeed exist (Einstein also played a critical role with his theory of Brownian motion). That Boltzmann’s assumptions were fundamentally correct was not a given, and that they led to predictions that agreed with observation did not prove them to be true. As Lindley notes: “You make an assumption and explore the consequences. This is exactly what scientists continue to do today, and the fact that a certain assumption leads to all kinds of highly successful predictions and explanations does not, strictly speaking, prove that the original assumption is correct.

Lindley’s portrait of Boltzmann is both the story of a man who had some very profound personal issues and the history of a branch of science that presaged the quantum revolution. The story of the advancement of science is fascinating in its own right, as generations of scientists tried to tease out what, at the microscopic scale, was driving the macroscopic observations we make every day. Lindley describes the scientific environment of the time, in which a few big heavyweights dominated the discourse. A single scientist, working in relative isolation, like Boltzmann, could make huge impacts on his field. This isn’t as true today, where we seem to be delving more into details than bigger swaths of truth. Not that there aren’t any new big truths to discover, but rather that the kinds of technological advances that are rewarded demand digging into the details. And, the democratization of science — the shifting of science being a rich-man’s hobby to a true profession pursued by large armies of people — have made it so that it is harder to stand out in the proverbial field.

As for himself, Boltzmann was never happy. He always desired more recognition for his achievements and that typically meant moving to bigger and better positions at other universities. However, the moment he accepted such a position, he was riddled with doubts and often tried to undo the appointment. Particularly in Austria, where appointments were at least brought to the attention of the royals, this led to some level of infamy for the poor man. His vacillations were likely a reflection of some deeper level of depression or other mental condition, as he ultimately took his own life.

Finally, Lindley also provides some metacommentary on the scientific process itself. This is both through the continual argument between people like Mach and Boltzmann (Mach particularly disliked theorizing, stating, for example, that “the object of natural science is the connection of phenomena, but theories are like dry leaves which fall away when they have ceased to be the lungs of the tree of science“) as well as his own observations: “Science demands an element of creativity, and an element of faith. The creativity comes in thinking up hypotheses and theories that no one has ever thought of before. The faith comes in thinking that these hypotheses, when shown to be useful or successful in some way, bear a relation to what is loosely called reality.” Late in his life, Boltzmann, spurred on by the attacks by Mach and his followers, turned toward philosophy, in an attempt to understand the nature of truth. However, he never really became a philosopher, telling a colleague “Shouldn’t the irresistible urge to philosophize be compared to the vomiting caused by migraines, in that something is trying to struggle out even though there’s nothing inside?

Altogether, Boltzmann’s Atom is an excellent portrait of a man and of an era in science. It is a lesson in how science advances, not necessarily through the unstoppable march of progress, but in fits and spurts as different personalities come and go. Boltzmann himself is an intriguing figure that bridges two different eras of science. We tend to forget both that science doesn’t always follow an obvious linear path in the search for understanding and that the people that push it forward are human with very human foibles. Boltzmann’s Atom reminds us of both.