A few years ago I was having fun of thinking about the fluid dynamics of a ball moving through the air. The main focus was beach volleyball, but also several other sports that use roughly spherical balls. Of these, the two with the most curious motions are table tennis and beach volleyball. It came as a surprise as soccer (football in most of the world) has dramatic movements and baseball can be tricky, but they're not in the league of these two other sports. People found it fun so I decided expand it into a college level class - a one semester physics of sport course for non-majors.
It was a very interactive affair,. After a few weeks a few coaches and their assistants turned up, offering things to think about. After going through the Fosbury flop, one of the track and field coaches mentioned there had been a similar innovation in long jump, but it had been outlawed as too dangerous. He pointed out you lose a lot of energy at takeoff by leaning back at takeoff. The innovation was to halt the loss doing a forward somersault. He couldn't remember the name of the athlete who did it, but thought it was in the mid 70s with World Athletics quickly banning it.
That evening I took pencil to paper and came to the conclusion it could increase distance traveled by as much as ten percent. Ten percent is a change in sport where people will try crazy things for fractions of a percent. Eventually around I found the athlete - a student from New Zealand who would have had the world record on his first attempt if he had slightly better form. There were a few still images, but no video.
With the recent passing and celebration of the life of Dick Fosbury I decided to look again. Two years ago an interview with a video of the jump was posted. Long jump records would probably be over ten meters if it hadn't been banned. The physics is simple - the leap was realizing you didn't have to lean back.
It turns out we make it up as we go along and that's a foundational piece of why it's been so successful.
Apparently there's been some discussion about the connection of physics and some quest for an ultimate truth on a social media site I gave up. A few people reached out and asked my opinion. Starting down the path as a teenager, I thought science was after some deep and ultimate truth. Some grand and beautiful underpinning of the Universe. I was wrong. It took time, but finally as a grad student I had come to know better.
What physics does is build mathematical models that describe observations. (why math works so well is another discussion - but it just does) The hypothesis models that are robust enough to survive different experimental techniques and are predictive become accepted theory. It's very much an iterative process and the models get progressively better with more predictive models coming into use as appropriate. The Standard Model is the best we have for particle physics. It has some warts, but it's far and away the most accurate theory devised. General Relativity is the benchmark for gravity. Both are under constant study and that study has led to radically different views of the Universe and how it has and will evolve.
But to the question from the birdsite. What is real? Is a proton real and what is it made of? What about the spin of a particle? Is dark matter or the dark force real? For the electron and the quarks and gluons that make up protons and neutrons, the most accurate and way to think about them is as excitations in fields that spread throughout the universe. You, the computer screen you're looking at, your dog and your lunch are vast assemblages of field excitations. It's far from intuition and these models are rarely taught until the junior year and that's usually at a high level as the math is a bit intense. It may seem weird, but it's much more predictive than anything else. And gravity being spacetime that changes it's curvature around mass and mass that responds to the curvature of spacetime isn't exactly Newton's falling apples.
Current accepted theory addresses serious flaws in earlier work. The earlier work was good enough given the sophistication of measurements, but tools improve with time. It turns out most (but not all!) of applied physics and engineering doesn't have to worry about these deeper descriptions as these are fields that usually apply to things roughly our size moving a low speeds. There's an interesting notion called complementarity that tells you it's okay to use less precise, but easier to understand, models when you don't need extreme accuracy. We live in a world where models with a Newtonian underpinning are usually valid.
In a way it's how we perceive things. We only sense a tiny amount of the electromagnetic spectrum, our hearing misses quite a bit, our sense of time misses large and small intervals and our size is roughly between that of the Sun and a hydrogen atom. We don't perceive much of the reality around us - we have to use our imaginations to figure out how to ask the right questions and see more deeply.
So we build models. We don't work out the equations of motion, but we walk, throw balls, drive cars and so one. We have a fair amount of information for these simple actions. Physical models quickly get more difficult. How do you predict an earthquake and its severity? When and where tornadoes will do damage? We build approximations, but that's all they are. Better models will come using the scientific process. Even if it's a messy undertaking, it's proven to be the best approach we have. And there's a foundational principle you have to deal with - one that Feynman famously articulated:
The first principle is that you must not fool yourself and you are the easiest person to fool.
More complex and social sciences come into play. Predicting markets and economic models don't have the twelve digit accuracy seen in the Standard Model .. they generally don't make it past the decimal point. They're also a stab at reality. Social models are often poorly constructed with bad data and analysis - a major "AI" issue these days. And how we understand each other as people. We all build models. Hopefully they're good enough.
For a long time I believed you could change minds about the causes and threat of global warming through education.Silly me - it turns out to be a fool's errand. We all have different views of reality. We can witness an event and see differing realities. These lenses can be very different and culturally driven. Quite a bit of work has been done trying to understand how this works. Recently a podcast chat with psychologist Jer Clifton was recommended by Corinne. I give it two thumbs up and recommend it to anyone who has to deal with other people in almost any capacity. It may even make you think twice about how you interact with others.
The chunks of plastic held the ghosts of magnetic fields produced by some of our gadgets and appliances. Shuli's pieces were quite beautiful and had me thinking about visualization on the train ride back home.
We only see fragments of the real world, but our brain stitches what it can find together into a fleeting proxy for reality. It's turned out to be good enough of what we do, but I recommend An Immense World by Ed Yong for a look at how evolution has equipped other lifeforms. (It's a wonderful science for a general audience book - my favorite for 2022) Science tries to sort out what is real and physics often seems foreign to what we're used to. On the train ride home I was thinking about how we visualize electromagnetic radiation - specifically a question someone had asked a few years back.
What would wifi look like if we could see it?
It seems relevant if you're trying to figure out how walls, refrigerators and other objects in a house or office interact so we know what the signal strength might be. People who do this either just measure and plot signal strength or have simple models to give them a heat map that hopefully approximates what they would measure. None of these gets at the real question.. what do wifi signals .. and all the other electromagnetic radiation that surrounds us look like?
The equations are straightforward and I suspect many imagine what it might look like when doing calculations - at least the parts we're looking at. But these representations aren't rich enough. The real appreciation is in the mathematics. Feynman commented on it back in the 60s:
I have asked you to imagine these electric and magnetic fields. What do you do? Do you know how? How do I imagine the electric and magnetic field? What do I actually see? What are the demands of scientific imagination? Is it any different from trying to imagine that the room is full of invisible angels? No, it is not like imagining invisible angels. It requires a much higher degree of imagination to understand the electromagnetic field than to understand invisible angels. Why? Because to make invisible angels understandable, all I have to do is to alter their properties a little bit-I make them slightly visible, and then I can see the shapes of their wings, and bodies, and halos. Once I succeed in imagining a visible angel, the abstraction required-which is to take almost invisible angels and imagine them completely invisible- is relatively easy. So you say, "Professor, please give me an approximate description of the electromagnetic waves, even though it may be slightly inaccurate, so that I too can see them as well as I can see almost invisible angels. Then I will modify the picture to the necessary abstraction."
I'm sorry I can't do that for you. I don't know how. I have no picture of this electromagnetic field that is in any sense accurate. I have known about the electromagnetic field a long time I was in the same position 25 years ago that you are now, and I have had 25 years more of experience thinking about these wiggling waves. When I start describing the magnetic field moving through space, I speak of the E and B fields and wave my arms and you may imagine that I can see them. I'lI tell you what I see. I see some kind of vague shadow, wiggling lines-here and there is an E and B written on them somehow, and perhaps some of the lines have arrows on them -an arrow here or there which disappears when I look too closely at it. When I talk about the fields swishing through space, I have a terrible confusion between the symbols I use to describe the objects and the objects themselves. I cannot really make a picture that is even nearly like the true waves. So if you have some difficulty in making such a picture, you should not be worried that your difficulty is unusual.
Our science makes terrific demands on the imagination. The degree of imagination that is required is much more extreme than that required for some of the ancient ideas. The modern ideas are much harder to imagine. We use a lot of tools, though. We use mathematical equations and rules, and make a lot of pictures. What I realize now is that when I talk about the electromagnetic field in space, I see some kind of a superposition of all of the diagrams which I've ever seen drawn about them. I don't see little bundles of field lines running about because it worries me that if I ran at a different speed the bundles would disappear, I don't even always see the electric and magnetic fields because sometimes I think I should have made a picture with the vector potential and the scalar potential, for those were perhaps the more physically significant things that were wiggling.
That said I find myself using my mind to fly through through these abstractions of reality that experience and imagination provides. I suspect people do this differently. It isn't something that lends itself to drawing as it's often dynamic and, even though I consider myself extremely visual, not entirely visual. While I find many computer visualizations useful, they don't keep up with the imagination. I suspect no two people imagine quite the same.
A few nights ago Sukie and I were startled to learn something about her visualization. I was listening to The Case of the Blind Mind's Eye - an episode of an excellent BBC science and math podcast. I strongly recommend listening to the episode. They were talking about the mind's eye .. how we conjure up images in our mind. If I ask you to think about an orange giraffe with purple spots, an image appears in your mind. Or at least it does for most people. Aphantasia is a semi-rare condition of people who are unable to generate these images. It's completely fascinating and you need to listen to the show. Sukie heard a few comments and had me go back to the beginning. It turned out she has aphantasia - she's unable to form mental images and is startled that others can. She's suspected comments about the ability are just a figure of speech.
Aphantasia is more of a difference than a defect. Sukie is extremely clever and has done impactful work in a few areas. It turns out there are benefits.. it's another way the brain can imagine. Ed Catmul (Pixar) has it and managed to create a revolution in how computers create images. The same for Glen Keane - the Disney character artist who created Rapunzel, Ariel and a score of other important characters. He describes his process as "thinking with a pencil". The shapes and forms come as he draws in a very fluid and gestural motion.
It may be a spark, perhaps a necessary one, for very out of the box thinking. In the meantime artists and the process of doing art can unlock the imagination. It's not a full representation and perhaps that's what makes it so powerful. It raises so many questions!
The short version is it’s a remarkable technical and scientific achievement. Controlled human-made power from fission is easy - last week marked the 80th anniversary of the first reactor. Fusion - what powers the stars - is much more difficult on Earth. The necessary temperatures are far greater than those found in most stars. A star like the Sun gets away with a very slow and low power density reaction that would be impractical for generating power on Earth. It turns out the power density of the core of the Sun is about a quarter of your metabolic density and close to that of a lizard. To get around this different fuels are needed along with much higher temperatures. Still, if you can only figure it out, it sounds like the perfect goal - fuel from water and no radioactive waste.
The first serious attempt at magnetic confinement look place about 60 years ago .. it, along with every other effect until this last week failed. Those that achieved fusion required more input power than the power they produced. The figure of merit is Q: the ratio of the power of the fusion reaction divided by the power required to ignite and sustain it.
The laser confinement experiment announced focused a short pulse of light - about a billionth of a second - from 192 lasers onto a small gold container that vaporized to generate x-rays that collapsed a diamond coated fuel pellet of deuterium and tritium. The power of the laser light was 2.05 MJ (megajoules — a gallon of gasoline is 121 MJ, a hot dog in a bun is about 1.5 MJ) and the fusion explosion yielded 3.15 MJ. A Q of about 1.5. What isn’t mentioned is the efficiency of the lasers or the facility isn’t included - or the efficiency of extraction power from the miniblast. The lasers are less than one percent efficient so you can see there’s a long way to go.
This facility has been running for about a dozen years. It has been solving enormous engineering and applied science problems along the way as well as contributing to the pure science of understanding plasmas at this scale and temperature. Even the fuel pellets are very difficult to make and test. They have to be extraordinary symmetrical and most are rejected in testing - usable pellets are very expensive. What has been achieved is not a prototype, but rather a triumph of instrumentation technology along with the control of some difficult to manage parameters.
Moving this line of fusion forward seems like a long shot. A factor of five improvement may be possible with a redesign, but they need more than a thousand. Not impossible, but there’s a long path ahead.
There are other design types that confine microwave heated plasmas. Getting it right and working will take many years - probably decades and then there’s the issue of what does a facility cost compared to other types of power stations.
I hope work goes forward, but not at the cost of workable technologies that address global warming *now*. There’s so much that can be done, but very little political will.
Compton: The Italian navigator has landed in the New World.
Conant: How were the natives?
Compton: Very friendly
Almost exactly 80 years ago the first human-made self sustaining nuclear reaction took place under the stands of a vacant football field at the University of Chicago. It's a remarkable story and something of a race with Nazi Germany. Fortunately so many competent physicists had fled Germany that the Nazi bomb project was a failure. It turns out the wikipedia article on the subject is an accurate and readable summary of the dawn of the pre-manhattan project effort to get a handle on nuclear fission. The piece gets a bit technical here and there, but you can skip over those parts if you like. I'll try and give a high level view of what a sustained reaction is without going into the quantum mechanics of the process.
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Nuclear fission is the process where the nucleus of an atom breaks apart into smaller pieces releasing energy (often quite a bit) in the process. The nucleus of an atom is a tight cluster made up of positively charged protons and electrically neutral neutrons.
All of those positive changes packed together - you might ask why don't they fly apart? After all, electromagnetism causes like charges repel. It turns out a very strong force, cleverly called the strong force, acts on neutrons and protons binding them together. A difference between the two forces becomes important. Electromagnetism is a long range force while the strong force only acts over short subatomic distances. To first order you can think of the strong force acting only between immediate neighbors while the electromagnetic force acts on all of the protons.
If the nucleus gets big enough the total repulsive electromagnetic force of all of the protons overcomes the closest-neighbor strong force and breaks the nucleus up in to smaller pieces releasing energy in the process (nuclear fission)
Most of the elements we're used to have nuclei that are too small to break up on their own. A few are on the borderline. In the case of uranium the addition of a single neutron is enough to undergo fission and in the process it releases energy and, on average somewhat more than two extra neutrons along with a couple of nuclei that are smaller than uranium.1
In nature uranium usually isn't concentrated and the neutrons from fission are absorbed by other materials.2 But if you concentrate uranium you get to a point where each fission has a high probability of striking another uranium nucleus and so on - creating a sustained reaction. Unchecked, with enough purity, and you get an atomic bomb. At lower concentrations and with the ability control the amount of neutron absorption you get a controlled nuclear reactor that liberates a useful amount of energy.
A number of interesting characters were involved in these early experiments. Enrico Fermi was the key player in the first sustained reaction. Physics was getting specialized and he was probably the last physicist who was both a great theorist and experimentalist.
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1 I've left out a lot. I haven't mentioned which isotope of uranium for example. Also - you may have noticed that adding an extra neutron shouldn't increase the electromagnetic force as the neutron is neutral. It turns out the uranium nuclei is so close to breaking up that the kinetic energy of the addition neutron adds just enough to break things up. A nice example is adding a neutron to U-235. One possible fission chain n + U-235 → Rb-92 + Cs-140 + 3n + 200 MeV of energy.
Also details of the strong force weren't known at the time.. A clear hypothesis didn't arrive until about 30 years later and deeper details of the mechanism took almost thirty more..
2 A natural formations of uranium t pure enough to initiate sustained nuclear reactions was discovered in Gabon. It operated for a few hundred thousand years producing less than a megawatt of power.
It’s a clear winter night as I write these last words. I’ve stepped out to look at the sky. With the stars up above and the blackness of space, I can’t avoid feeling awe.
How could we, Homo sapiens, an insignificant species on an insignificant planet adrift in a middleweight galaxy, have managed to predict how space and time would tremble after two black holes collided in the vastness of the universe a billion light-years away? We knew what that wave should sound like before it got here. And, courtesy of calculus, computers, and Einstein, we were right.
That gravitational wave was the faintest whisper ever heard. That soft little wave had been headed our way from before we were primates, before we were mammals, from a time in our microbial past. When it arrived that day in 2015, because we were listening—and because we knew calculus—we understood what the soft whisper meant.
Steve Strogatz
Chatting with a friend the subject of gravity came up. It isn't a conventional force, but we perceive it as one. Rather it's connected with the curvature of a four-dimensional object called space-time that we happen to live in. The fundamental concepts aren't intuitive and the math that describes it is beyond what you might get in an engineering degree. So how to describe it? There are very high level books and videos that speak in terms of balls on rubber sheets and then jump to oddities like clocks running faster on mountain tops and blackholes. I usually find them a bit fluffy and disappointing. They're bound by assumptions about their audience, so it's not a major criticism. It's just that I was talking with one person and something a bit deeper seemed appropriate. Just how do you find the right level and where do you go from there?
A few years ago Wired produced the 5 Levels series. An expert would try to explain something about a complex subject to five people: a child, a teenager, an undergrad majoring in the same subject, a grad student and, finally, a colleague. My favorite is Donna Strickland on lasers - give it a watch, she's excellent:
I went through something like this just before my Ph.D. thesis defense. I was to explain my thesis work to a group of high school students. At first I thought it would be easy, but that notion quickly evaporated. It turned out to be one of the most difficult and embarrassing things I've done. My advisor stepped in near the end of the talk and summed everything up beautifully. Afterwards he told me if you understand something deeply, you can explain the gist of it to a high school student. That's high on the list of the most important things I've learned.
My friend has a BA in biochemistry and knows about differential equations so I figured I should aim for something between the vague videos and what a senior level general relativity course offers. The more I thought about it I realized it would be best to talk about the history and use a bit of calculus and geometry. I had the advantage of knowing her well and she can stop and ask questions or give a blank look along the way. And afterwards she was going to talk about something where she has serious expertise.
Steve Strogatz is an applied math professor at Cornell. He's written several books including the one the opening quote is taken from: Infinite Powers: How Calculus Reveals the Secrets of the Universe. It's an excellent read that makes no assumption on your mathematical background.1 Thinking about it gave me some hints of how I might proceed.
First why do I have to use math? Why won't words work? The laws of nature obey logic that we can make predictions from. Math, calculus in particular, is a logical calculating tool. In a way it's a prothesis. Math lets us take a bit of logic, write down and perform logical manipulations that far exceed what we can do in our head, and then interpret the results. The logic can be crafted to represent something about the science. Every once and awhile the results can make predictions that can lead to new discoveries, but more often they're used to to solve an enormous range of problems. And why calculus? Much of the underlying structure of nature has been successfully expressed with the corner of calculus known as differential equations. "Why?' is a deeper question. If one encountered an intelligent alien who understood some aspects of how the Universe worked, I suspect they'd use math. I suspect, but it's only my suspicion, that it's deeper than an artifact of how we think about things.
I spent a couple of hours writing. How general relativity came about, a bit on the structure of space-time, what goes into the main equation and how a simple prediction could be calculated. Then about an hour of chatting that left me with two delightful philosophical questions that will probably lead to more discussions as well as her turn to teach me something.
Whatever your expertise, it can be fun to try and explain the gist and maybe even the beauty of it (those can be he same thing) to someone with a very different background. If you're like me you'll fail at first, but eventually you'll get to a point where you can find the right grounding, the right words and perhaps the right drawings or even music (some of you are artists and musicians).
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1 By all accounts he's a wonderful teacher and has become a popularizer of math. Among other things he's created a college course at Cornell for people who think they're afraid of math and have generally put it off until their senior year.
There's so much that isn't fair in this world, but most competitive sports make an attempt to provide a reasonably level playing field through the establishment and enforcement of rules and categories. Rules vary from sport to sport but some constants are the elimination of performance enhancing drugs, a degree of safety for participants, and the creation of categories. Some sports allow a certain amount of violence or danger balancing what the fans and athletes want vs modifications to the rules that might make the sport less desirable. In other words there's a social convention. Sometimes that social convention changes after serious injuries or deaths. Positive change has come in world rugby in the past few years, but other sports are more resistant to change.
More recently fairness and inclusivity have come into play. Categories exist to prevent grossly unfair contests. You don't want a wrestler up against someone half their weight. Twenty year olds don't compete with ten year olds or seventy year olds. Men and women usually are have categories of their own in most sports. And para-athletes generally have separate competitions with a dizzying set of subcategories to allow fairness given a wide range of capabilities. Fairness comes first in these, but it allows inclusivity to play and potentially succeed in a given sport. But like so much else in the world there's change.
South African Oscar Pistorius became a below-the-knee amputee in both legs as a child due to a congenital defect. Using racing blades, he became a good sprinter - an Olympic class sprinter. There was controversy about how much of his performance came from him and how much from the blades? Are blades as good as or better than real lower legs? He was charismatic and there was a large amount of social pressure that running should be inclusive. A few calculations were done early on followed by a few real tests with this unusual subject. Some of the early results indicated the energy return from the carbon-fibre blades was the same as the achilles tendon - in other words no advantage. That was the message the public received. The more careful work that followed has shown he had a significant advantage from lower contact time with the ground and added leg length - enough that 'he was probably a good, but not elite runner turning in performances well beyond his athleticism. The blades are performance enhancing prosthetics.
Performance-enhancing blades raise an interesting question. What if a world class runner adopted them? Would a 9.30s 100 meter dash be fair? How about a 1hr 50m marathon? Would elite runners have to get amputations to compete? Fortunately the really elite runners are staying away from this, but now we have another very good runner trying to compete. Sports physiologist Ross Tucker has a great interview with Peter Weyand - one of the best biomechanics physiologists on the science and pseudoscience involved. If you're interested in these things start at about 26 minutes in this episode.
There will be innovation. What happens in field sports that demand good court vision with augmented reality glasses? Will they be banned and in what sports? Will performance enhancing prosthetics for stick and racket sports come about? What is pure and fair and where does inclusion fit in?
And now to a socially charged issue: transwomen and female sports. To first order biological sex has two categories while gender is a continuum. I think that gender should not be a category for discrimination, but that biological sex should be used to establish categories for fairness and, in some sports, safety. There's a good deal of solid science that shows male puberty results in advantages in size, muscle mass, VO2 max and a few other metrics. These advantages are important in most sports and would exclude biological women from the elite and next to elite categories in most sports where men compete.1 Testosterone is cited as the advantage, but suppressing it later in life only results in a small drop in performance (there are a few poorly done studies that claim otherwise). This has become a social issue with a rightwing party calling for blanket bans in many activities including sports. There's been pushback by allies. In some cases female athletes have been threatened by sponsors to not speak out and go along with inclusion rather than fairness. Should transathletes compete with men, females, or have their own category? That seems to be a social decision that only a few sports bodies have addressed at this point.
I'll admit to a bias.2 I believe in solid science and fairness. I think transwomen need to compete with men or have their own category. Politically I'm on the left on most issues and think transpeople should work and live how they want, but that doesn't extend into sport where categories exist for reasons of fairness. Fairness to women overrides scientifically unsupported inclusion in my mind.
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1 A chart showing the performance difference between biological male and female elite athletes. Longitudinal studies show a drop in male advantage from 5 to 30% after three years of testosterone suppression and a non-longitudinal study showed a similarly small drop after about 15 years.
In the real world this means a transwoman swimmer who was poorly ranked as a male was able to easily defeat all of his NCAA female competitors even with a few years of testosterone suppression. In sprinting it has been shown that biological Olympic gold medal females don't even make it into the top 2,000 for men. It has been posited man ranked 1,000 could easily beat any women even if he had testosterone suppression that dropped his advantage by 30%.
2 I have an involvement with beach volleyball and love both the men's and women's game. I know a few Olympians on the women's side who sometimes train with amateur men who easily outpower them. The fact the women are less athletic doesn't make their game less interesting.. it's just that the two styles of play are very different.
37 and 73 are reversible primes , 37 is the 12th prime and 73 is the 21st - another reversible pair
and ....
and ....
and ....
It arrived in a lovely wooden box with polished brass hinges and was written in a nearly calligraphic hand. Skipping about fifty pages was the conclusion that said its author had found the number 37 was key to gravity and electromagnetism and was being unfairly ignored.
I thought about the first two statements for a few seconds - they were of the form (100x + 10x + x)/3x or 111x/3x = 37 for the integers x = 1 through 9. No surprise.
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Universities with famous physics professors get a lot of mail from people out to prove something. The amount of effort is often as astonishing as how wrong the work is. Some universities farm out this mail to upperclass undergrads and grad students as a filter as well as an education. It's true that every once and awhile there's an unknown genius - Ramanujan's letter to Hardy being the most dramatic example in history - but those days are probably gone and Ramanujan was already known in India.
Creativity isn't terribly useful without background and a level of competence. But where does it come from? I'm certainly no neuroscientist, but talk to a few and there's quite a bit of new work going on these days. Some of it is from fMRI imaging.. a technique that can map active areas in the brain while a person is thinking. It seems most early work would have subjects were told to rest between tasks while new trials were prepared. The machines are quite noisy and produced enough data that it only made sense to run them during the active trial. Finally someone decided to look at what was going on when minds were just wandering.
Your brain accounts for about a fifth of your resting energy demand. Surprisingly focusing and thinking deeply about something uses about the same energy as an unfocused wandering mind. When fMRIs were finally used to look at the unfocused wandering state it was found the brain was lit up, often with widely separated areas firing at the same time. It's known as the default mode network. Mind wandering - like when you suddenly realize you can't remember anything about the past six miles you've driven - accounts for nearly half your waking mental state.
Some cognitive neuroscientists - Moshe Bar for example - believe these ramblings may be associated with mood - ruminating ramblings and their connections can lead to worrisome states while creative wanderings can lead to happy moods (this is speculation and there are many other states). It's also noted that your more conscious states can range from exploratory to exploitatory. You seem to be able to know when you should focus and get something done or be open to new things.
Much of what Moshe says squares with how I think about creativity. That doesn't mean it's right, but it strikes this non-specialist as being on the right track. I try to leave the day open and certain times and remove distractions to allow for small creative moments and put myself in the mood by drawing. More important is building a supply of seemingly unrelated potential connections through reading, hobbies, travel, friends and so on. In my case a curious set of friends is central.
The most creative organizations I know tend to have a number of foci and unrelated specialists. I have a relation with one that has almost no overlap with what I do, but pre-pandemic they'd fly me out for a couple of days every year to wander around and drop in on their folks as well as give a little talk. They seem to value it, but I'm the one who probably benefits the most. In a few of these companies internal measures of creativity dropped during the pandemic. Perhaps those semi-random face to face interactions are very important. It's possible, but difficult, to recreate some of that online despite what Meta would try and tell you:-)
Of course there's a bit of speculation here and what works for one person may not for someone else. Major creative moments are rare, but at least we can make the smaller ones more likely. And hopefully blending these moments of creativity with a background of expertise can be useful.
I wish I could have kept the wooden box. It was beautifully made. But its content made a big impression.
The first military airplanes designed after WWII began to arrive in the late 1940s. A number of these early jets were more complicated to fly and the number of incidents and accidents alarmed the military. Incidents where something went wrong, but the pilot and aircraft came back safely, and accidents were more serious. As the jets were mechanically more reliable than their piston powered WWII era cousins, it only seemed natural to blame pilot error.
A few remarkable pilots would find themselves in a bad spot, but always manage to get themselves out of trouble - often saving the aircraft. Chuck Yeager was the legendary master and was sent to airbases to show pilots how to fly correctly. But the fact was this was happening to very skilled pilots. With pilot error and aircraft malfunction seen as less likely root causes, eventually cockpit design was questioned.
Military airplane cockpit measurements were based on an average of a few measurements of about a hundred airmen in the mid 1920s. Improved nutrition and larger pilots was suspected as changing the average, so a massive study was undertaken that took 140 measurements of nearly 4,100 pilots. In theory this would lead to a better average cockpit.
Gilbert Daniels joined the medical division at Wright Patterson out of college and was one of the people tasked with making these measurements and coming up with averages. It turned out he was biased. In college he did some research trying to find an average hand size and found it impossible. Sifting through the data he looked at ten measurements deemed most important for the cockpit and calculated an average range for each that included 30 percent of the measurements - a nice wide average. The surprise was than none of the pilots fell within all ten of the wide averages. Gilbert found if you picked any three of the ten, less than four percent of the pilots would be average. No one was average.
It shouldn't have been a surprise. Women's clothing designers had known it for awhile - something attributed to women being "different." Eventually the military believed Gilbert's work and mandated highly adjustable cockpits. All new aircraft had to be adjustable for males in the 5 to 95 percentiles for each of about ten critical dimensions. Airplane manufactures balked - "it can't be done", but finally came around because .. well .. contracts.
The fifties saw more adjustability come to automotive interiors, but at a much slower and more incomplete pace than military aviation. About ten years ago I found myself driving a friend's Japanese sports car on the Pacific Coast Highway. A lovely car considered one of the best handling in the world, but I didn't fit - there was no way to adjust the seat or steering wheel enough. I'm not particularly tall, but have short legs and a long torso. I also have very long feet (in theory the right dimensions for a swimmer, but not my thing). A few months later I was helping a friend move in a rented truck. The same problem. There weren't enough adjustments to prevent my feet from getting caught near the pedals. And then there's automobile safety. The instrumented dummies used in crash tests cover less than a quarter of adults bringing into question the tests themselves.
And it's not just physical differences. 'What color is the dress?' became a popular question as people legitimately came to different conclusions. Tonal language native speakers are much more likely than other populations to have "perfect pitch." Some people are purely visual thinkers, but most are a mixture of audio and visual. There are people with very poor stereo vision - I know one who is an animator. Increasingly "on the spectrum" is a meaningless construct. Our brains have so many differences - so many dimensions - that it's likely none of us are truly "normal." This has become an issue in fMRI studies recently. For example studies showing differences between men and women are often in the noise and meaningless. The field will eventually get more rigor. You really need to know what dimension you're measuring.
Finally there's neuroplasticity. We know that kids undergo huge changes in neural connectivity as they grow and some areas of the brain aren't stable until the mid 20s. (I have a neurological condition that is believed to have resulted from an incomplete severing of neural connections when I was a baby. It isn't a big thing, but is different enough to be worthy of study). One seen as stopping around 30, neuroplasticity is seen throughout life, albeit at different rates. There are examples of dramatic repurposing of regions of the brain. Helen Santoro's missing left temporal lobe is one of the more dramatic examples.
After two billion seconds on this planet, you tend to think about the time you've occupied and what you may occupy. Our ability to sense scale is largely limited to what we can sense and the physical and temporal spaces we navigate. Historians usually work with somewhat larger scales, but I'm guessing they don't have a good feel for - say - what 917 AD actually means. Science looks at larger and smaller time scales. I've spent a lot of time worrying about processes shorter than a femtosecond as well as those that are billions of years long. I write down the scientific notation, but confess I don't have a physical feeling for what it means.
I'm particularly interested in what we can do about the future. Dealing with global warming as a practical matter to mitigate huge biological and financial losses would see to be the big challenge (hopefully we'll see enough progress!). On the scientific side there are projects that span decades. Initial work on CERN's Large Hadron Collider began in the late 70s and it should run through at least the mid 2100s. Solar system exploration often looks three or more decades out. Voyagers 1 and 2 managed to capture the public's imagination early on and they continue to provide amazing results - over 44 years from their launch. (you can find out how far they are away and how fast they're moving at this JPL site)
The genesis of Voyager came when a Caltech grad student was working on a Summer project at the Jet Propulsion Laboratory in 1964. Gary Flandro was studying techniques to send probes to the outer solar system. Even during the space race the scale of space made this look completely blue sky. Gary realized an alignment of Jupiter, Saturn, Uranus, and Neptune would take place in the late 70s and that it might be possible to make a "grand tour" of these planets if you used gravity assist - a mechanism that transfers a bit of the kinetic energy from a planet to a spacecraft - to speed up the journey. Such alignments are rare on the scale of a human life - about once every two hundred years. The project was funded and, with help from Carl Sagan, caught the public imagination with a golden record of humanity attached to the spacecraft as well as one of the most iconic images humanity has recorded - the pale blue dot.
Exploration of the planets of the outer solar system was the prime mission. The fly-bys were smashing successes, but the two spacecraft kept working. Instrumentation was primitive by today's standards and optimized for conditions expected around Jupiter and Saturn, but it was possible to track the solar wind and a few other things.
In 2004 Voyager 1 crossed the boundary of the heliosphere - a huge region surrounding the Sun inflated by the solar wind. There was celebration as something made by humans had crossed into interplanetary space 94 times as far from the Sun as we are. There was a shock in 2007 as Voyager 2 traveling in a different direction, crossed the boundary about ten percent closer to us. The nature of the boundary was also different. It was, and is, a time of delight as so many new questions and hypotheses formed.
I'll skip the details, but there are two protective regions that deflect charged particles that help make life as we know it possible on Earth. The smallest and most important is a comet-shaped region around the Earth generated by our planet's magnetic field. This magnetosphere deflects charged particles streaming at us from the Sun as well as some cosmic rays from deep space. Without it much of our atmosphere would have blown away and radiation levels would be high on the Earth's surface.
The much larger heliosphere defects cosmic rays from outer space. We've learned that the Sun has been traveling through a dust cloud known as the local interstellar cloud for about 60,000 years. We're currently at an edge and soon we'll be on the outside (this may have already happened!) Then we travel for about 2,000 years before entering another dust cloud called the G cloud. Depending on its density the heliosphere may shrink. Cosmic ray fluxes would increase and that raises an interesting set of questions.
[speculation alert] Between two and three million years ago some crust samples show a lot of Iron-60. The isotope does not occur naturally on Earth - rather it's the product of supernova explosions. We may have spent time passing through a cloud laden with the "ash" of these huge explosions. The heliosphere would have shielded us from charged particle radiation levels that would have done a number on life on Earth, but some would have made it through. Who knows - perhaps this had an impact on evolution? In any event there are a huge number of questions.
A number of fantastic missions to the outer solar system on the drawing board - missions that may find the first extraterestial life. I probably won't be around to learn about the findings, but am an enthusiastic supporter. One of the most interesting is a follow-on to the Voyagers - probes that dip their toes into interstellar space. A study project is underway in the US and the Chinese are talking about a mission. Details on the US proposal are amazing. It's modern day cathedral building with details that must work forty and fifty years out when most of the designers are probably gone and the world will probably be a different place. Thinking about it makes the hair on your back stand up.
In addition to the scientific and engineering challenges, there's also a management challenge. How do you form a cohesive team of experts who will have to excite and train new people along the way? These projects tend to be small and the loss of one expert can be a disaster. A great book that covers the New Horizons mission to Pluto and beyond shows how it can be done: Chasing New Horizons by Alan Stern and David Grimspoon.