omenti

hints on how our brains adapt to deal with new concepts

Humans have seen an amazing progression of ideas from basic survival skills to getting a handle on how the universe began and might end and a great richness in between.  We do this with a brain that hasn't changed much in the past fifty thousand years.  How do we do it?

 

Here's a quick summary of some work at Carnegie Mellon University that used functional Magnetic Resonance Imaging as a probe to see how physicists organized conceptual properties.  fMRI is a rather blunt tool, but it was able to show how the brain organized the measurable and immeasurable.

 

Another striking finding was the large degree of commonality across physicists in how their brains represented the concepts. Even though the physicists were trained in different universities, languages and cultures, there was a similarity in brain representations. This commonality in conceptual representations arises because the brain system that automatically comes into play for processing a given type of information is the one that is inherently best suited to that processing. As an analogy, consider that the parts of one's body that come into play to perform a given task are the best suited ones: to catch a tennis ball, a closing hand automatically comes into play, rather than a pair or knees or a mouth or an armpit. Similarly, when physicists are processing information about oscillation, the brain system that comes into play is the one that would normally process rhythmic events, such as dance movements or ripples in a pond. And that is the source of the commonality across people. It is the same brain regions in everyone that are recruited to process a given concept.

 

There are a much broader range of deep concepts in physics that may well have separate organizations, but the technique here is very coarse.  They undoubtedly exist in many other occupations and one has to wonder how the mind of someone with a wide range of interests can dance around and play with different structures.  

 

Creative organizations need have internal access to a range of thinking modes and backgrounds. Like many others I have imposter syndrome when I'm listening to someone with deep experience in a different area.  Their mind has a great fluidity that you don't have became you lack the background and neural organization.  Breaking through this requires communicating at the appropriate level.  It's difficult if you don't know the other people.  One usually thinks of conventional academic subjects, but it's probably more general.  I find it amazing that some soccer or beach volleyball players create a mental map of the position, velocity, and acceleration of the other players including those they can't see and can bounce this off other information and communicate it to their teammate(s).  But great players run into the same problem as academic experts.  Finding the right level is difficult.  Great players rarely make great coaches.

 

Some organizations have worked out how to do this, but others tend towards narrow depth. If they appear to cover a broad range from the outside, inside they often are an array of poorly networked silos of local expertise.   Fortunately there seems to be a growing resistance to siloing.   And that brings me to a special kind of person.

 

Every now and again you come across a human impedance matches.  An impedance match is a bit of circuitry that allows as much of the signal as possible to go from sender to receiver (an over-simplification, but ...)  These people can sit between people with very different backgrounds or thought processes, often more than two, and make sure the signal gets through.    It astonishes me to see these people in action.  

 

breadth and depth

His parents were Danish, hers Swedish.  By some measures it was a mixed marriage with any number of small cultural differences. He noted and took delight in these small differences and ambiguities.  Rather than hunting, fishing or bowling he'd hike in the Summer and take long walks the rest of the year.   He liked to walk by himself and I suspect thinking about the stories he'd tell to friends and family about once a week.  He said storytelling was in his family and he had a great voice for it.      We'd sit in his yard and listen.   Some were short, some took a half hour.  They were imaginative with emotional moments coming in unsuspecting places.  They weren't the polished work of a writer, but left you wondering how he made those connections.  Only years later did I learn what an amazingly varied background he had and continually sought out.

 

My sister is a visual storyteller.  It took her half a lifetime to come to a place where she realized a single frame made of many images could be a short story that left you with questions and an open invitation to wonder.  She's extremely creative. The stories come to her quickly, but require a week or two to realize.  I suspect my Dad was a big influence.  He believed the best answers were incomplete and led to deeper questions.  He believed breadth was required to see simple answers weren't simple.  Corinne went for breadth, unfortunately I started down a path that was deeper than broad. 

 

A trigger for this post was a recent newsletter from David Epstein (The Sports Gene, Range).  He begins by talking about Emma Raducanu at the US Open:

Earlier this month, 18-year-old British tennis player Emma Raducanu won her first Grand Slam title. It was a shock; she entered the tournament with 400-to-1 odds. One of my favorite sportswriters, the Guardian’s Sean Ingle, asked Raducanu’s former coach about the factors that helped her talent blossom. Here’s what the coach said:

“From my perspective one of the best things with Emma is that she was exposed to a lot of sports from a young age, and didn’t go too specific into tennis straight away. I see that on court. When she’s learning a new skill, or trying something a little bit different, she has the ability and coordination to pick things up very quickly, even if it’s quite a big technical change.”

Raducanu added this:

“I was initially in ballet, then my dad hijacked me from ballet and threw me into every sport you could imagine. I was doing horse riding, swimming, tap dancing, basketball, skiing, golf and, from the age of five to eight, I was go-karting…From the age of nine I started motocross in a forest somewhere for a year. This was all alongside tennis.”

 

Although there are a few athletic geniuses like Tiger Woods who focus early, most elite athletes follow a very different path building a broad set of varied skills before specializing.   Epstein goes into depth in both of his books.  Outside of athletics, the generalists he focuses on in Range have richly diverse backgrounds. Something very different that the experience many have in trade school and college programs.  These people have built the tools they need to think creatively.  They're often better than narrow experts when confronted with a novel challenge.

 

 I'm sometimes asked to speak on the importance of STEM education at a local school and am doing it again.  I tell them STEM ok, but overemphasized in K12.  I think a broader liberal arts education leads to flexibility and creativity later on in life.  Unfortunately that isn't reflected in many (most?) hiring practices.  The lack of intellectual flexibility and diversity has lead to serous problems in some companies (tech in particular).   One can always add breadth later, but that can be inefficient once you're out of school.

 

I don't mean to disrespect STEM subjects.  Assuming the curriculum allows, they can be made relevant and exciting to those who won't use them in their work.   They add to breadth and can be a starting point for depth.   There are wonderful math and science books and teaching approaches that unlock wonder without getting bogged down in minutia.  Enough information and wonder that perhaps students will become citizens who can make informed choices.

 

Over the decades I've slowly broadened muself by talking to people and getting involved with their ideas and projects.  Many of you have your own diverse lists.  My short and incomplete list includes human powered airplanes, done strange things with sound, learned a little about animated film making, been around story tellers, learned a bit of anthropology and sociology, done art history research, learned about fashion and how clothes are made, learned a bit about diabetes, been involved in sandbending, the mental side of elite sport, and even know a bit about the fluid dynamics of balls used in sports.  Many of my guides and friends see this blog and I need to say thank you!   It amazes me how some of this triggers a thought in something I'm working on later.  You find yourself becoming more creative with age.  Who would have thought that the math for thinking about boundary layer separation on an almost non-spinning beach volleyball would help thinking about neutron star atmospheres.  Or the linkage between animation and fabric design, or...  the list goes on and on...   

 

Depth is great, but you need breadth to be creative.

 

 

on good design for those who need it

Olympian Sarah said she is more impressed by the achievements of Paralympians than Olympians.  She loves events like running with a guide and is particularly taken with goalball.  Goalball was invented after WWII for the blind.  The ball has two bells and the athletes have to use their sense of hearing to sort out where the ball is along with the other players.  It's stunning to watch.  (The first match is the gold medal match between the US and Turkey.)

There's a lot of interesting design in the Paralympics.  Sometimes the type of game, sometimes mechanical devices like special wheelchairs, and perhaps most important is a classification system to keep competition fair,  The amount of thinking that has gone into this puts many conventional sports to shame.  If you haven't watched any of the events go back and marvel at a few.  

 

Building proper access has been an uphill battle and people still fight against the Disabilities Act claiming it's "too expensive" or "just not worth it."  Getting the design right is a journey of its own.  A book that may change how you think about the built world is What Can a Body Do? by Sara Hendren. Solid recommendation!  This kind of design goes beyond physical affiances involving politics, law and sociology with the book addressing that and more.  The Paralympics are a shining example of it being done right in a limited area. 

 

This may seem a bit off topic, but I'd claim otherwise.  I've learned a lot from areas far from what I do.  Thinking about beach volleyball  led to a useful technique for studying neutron stars.   Get interested in something very different and you just might find interesting connections to something else.  Thinking about those with challenges is a rich area and probably useful for even non-designers to spend some time on.  It's a target-rich environment. 

 

 

on fundamental change

 

Ludwig Boltzman, who spent much of his life studying statistical mechanics, died in 1906, by his own hand. Paul Ehrenfest, carrying on the work, died similarly in 1933. Now it is our turn to study statistical mechanics. Perhaps it will be wise to approach the subject cautiously.

It's not uncommon for a professor to quote the first paragraph of States of Matter by D.L. Goodstein on the first day of an undergrad statistical mechanics course.  Statistical mechanics is an outgrowth of the study of thermodynamics which had become a major intellectual effort attempting to understand heat engines in the 19^th century.  You can derive the results of thermodynamics from it and it led to much deeper explorations including the beginnings of quantum theory.  It's also concerned with entropy.    Entropy is at the heart of understanding change.  It's deep enough to be tightly connected with why time only goes forward and what cause and effect are.  Popular definitions aren't accurate. It isn't the tendency to disorder and it isn't the entropy computer scientists talk about (although Shannon's entropy is an exceptionally important tool for thinking about information). 

 

Unfortunately the fundamental concept of entropy is a bit abstract.  xkcd notes a problem common in science and undoubtedly many other places.  I'm frequently guilty, but I started to put together a post on the difference between entropy and complexity and why increasing entropy doesn't imply increasing complexity that doesn't involve math.  I found myself sketching pictures and wishing they were animated.  Then I remembered Sean Carroll did a series of very short YouTube videos with Henry Reich creating the animations as part of Henry's Minute Physics series.  They're wonderful!

 

The third video: Where does complexity come from?,  gets at the core of the entropy and complexity and why entropy isn't disorder.  It works as a stand-alone, but I recommend watching all five in order.  They achieve a good balance of getting the basic concepts across without any danger of anyone committing suicide.

 

Sean begins with why doesn't time go backwards and covers a fair deal of what the Second Law of Thermodynamics implies.  Things like cause and effect, the origin of complexity and even how life can exist.

 

Some deep and sexy physics without the math.

 

 

playing with dimensions

Many occupations develop tricks to get "good enough" answers question.  These range from rules of thumb to shortcuts that are based on some insight.  In physics dimensional analysis - checking to see the technique or answer has the right dimensions - is important. After all - you don't want to measure someone's height and come out with an answer in pounds.   

 

The common shorthand is to use square brackets to denote the dimension of a physical quantity.   For a distance r [r] = L, velocity [v]  = L/T, g (the acceleration of gravity) [g] = L/T².  Generally M is the dimension for mass, L for length, and T for time. 

 

With a bit of additional information you can make quick estimates and even gain some insight.  Consider two athletes of similar build and physicality, but different heights.  One is six feet tall, the other five feet.  If you want to compare the power to weight ratio all you need to know is the power a muscle generates is proportional to its cross sectional area.  Their weights scale as the cube of their height, so  [power/weight] = L²/L³ or 1/L.  The shorter athlete has a twenty percent power to weight advantage.   You can use this type of analysis and freshman level physics to sort out why different sports dictate very specific body types at the elite levels of sport.  

 

Techniques like these are used during the early and very playful part of asking questions.  They can tell you if your approach is plausible or if it's going to be wrong.  Plausible doesn't mean right, but it's very useful to recognize what can't work so you can try something else.  It's a lovely way to learn by failing gently.  With time and experience you develop an intuition for what might work. 

 

One of these quick calculations is legendary.  A series of photos of the Trinity after the end of WWII.   Four stages of the explosion with a length and time indicators.  Details like yield were classified.  A British physicist didn't realize calculations were classified and did his own back of the envelope calculation in a few minutes.  His estimate was published and caused a kerfuffle worrying that secret information had been leaked.  

 

There wasn't a leak. The truth is many of the physicists involved made quick estimates that were good enough - enough to tell them the device's yield was about what they thought it would be.  They just didn't publish for obvious reasons. 

 

Here's my ten minute estimate using dimensional analysis and a bit of physical intuition. I'm avoiding a very difficult set of differential equations with some very messy boundary conditions - not to mention some quantities I have no way of knowing as an outsider.  To make it as simple as possible consider a spherical blast. The ground will have a minimal on the radius of the blast in the atmosphere, so ignore it.  The blast creates an expanding bubble that has to push against air outside the bubble. The most important terms in any expression will include the radius of the blast, the density of the air outside the blast, and the energy of the device.  There are many other things going on - this is just an attempt to see if a very simple high level relation of the relevant variables can be found in a few minutes.

 

Basically rearrange these terms dimensionally to see if you can find radius as a function of time after the device was set off.   Remarkably a simple relationship emerges.  So why not plug some numbers in?   The time and radius can be found in the photos and the density of air is well-known.    My radius measurement is crude - I know the device was on a tower and found a point that looked like the center.. draw some lines on a piece of paper, put it up to the picture and estimate 90 meters... perhaps a bit less.  A bit of arithmetic and a yield of equivalent to fifty thousand tons of TNT falls out.   

 

(pardon the handwriting, but it's much quicker and more natural than trying to typeset it)

 

 

The estimate isn't that far off - it gives you a good sense how the radius scales as the one fifth power of the blast's energy and to the two fifths power of time.  Those relationships are more illuminating than the estimated yield.  Since there are four images you could do something a bit more elaborate measuring all of the photos and making a plot of the growth of the fireball. 

 

 

 

objects and friction

Randall Munroe's xkcd is a necessary visit for anyone doing science, math, or engineering.   Artistically simple, he often sums things up with an almost poetic simplicity. Some have suggested topic ideas - he's taken two of mine and created beautifully distilled views of the underlying concepts that make me envious of his talent.  And he does it about three times a week.   Every now and again he creates something that resonates across a community.    It happened again last week:

 

 

Anyone who reads a lot of scientific papers recognizes this. Dozens of variations emerged overnight.  Some were very specialized - at least three relevant to astrophysics alone and I only know that because I know the community.    Here's one Abeba Birhane posted.¹

 

 

Serious truth!  A good deal of the community is this clueless.

It made me think of friction and objects.

 

One of the most remarkable features of physics is its simplicity.  While it may be non-intuitive and sometimes requires a bit of tricky math, you can remove complexity and discover underlying bedrock.  Once you understand the simple basics you can restore the complicating bits a piece at a time and describe a vast set of physical processes.  The fact that you can deconstruct and reconstruct so effortlessly is unique among the sciences.  It's why a physicist will tell you physics is the simplest science.  

 

Beyond physics complexity and emergent properties become important.  It turns out that asking "what is life?" is one of the most difficult questions. Working backwards from biology to biochemistry to chemistry to physics breaks down along the way.

But back to simplicity 

Students learning about motion and collisions start with a statement like "assume a frictionless surface."  Concepts become clear and it's easy to describe interactions where everything is understood.  Two blocks colliding elastically for example.  Later on you can restore friction.  Mechanical engineers, working in the real world,  are forced to deal with it.  In some of their systems - say a chain and gear bicycle transmission - it's possible to have efficiencies that exceed 99%.  Frictionless is the ideal here.  On the other hand you don't want frictionless tires or brakes - you'd never start and, if somehow put in motion, you couldn't stop.  The bicycle and road system is complicated enough that friction is good in places.  Fortunately good engineers know how to deal with such things.

 

The concept of "frictionless" has extended to interactions between computational objects and people.  In fact people are often treated as objects that contain a long series of properties.  Constructions like these lack the meaningful emergence that social creatures have. Serendipity and insight are often the result of social "frictions" in our interactions with other people.   We can have simple low friction interactions.  Sometimes they're great as we're not looking for much, but they're generally shallow.  A worry is large scale machine learning can create a faux sense that interactions with machines are deeper than they really are.  And many of these interactions are with other parties who make decisions about and for us. 

 

A few who build large scale social platforms have deep backgrounds in the social sciences and the humanities and think deeply about underlying social issues, but much of it is done without much clue by coders who build things quickly and then iterate to make them better - often more frictionless.  

 

Separately I had two wonderful reports from people at a very creative company.  Fully vaccinated people are back at the office with some precaution and maskless outside.  One reported she's had more insight and exciting ideas in the last week than in the last six months - largely through random talks with coworkers where they could "read" each other.  I hope all of you find the light at the end of the tunnel soon.

__________

¹ She's a cognitive scientist from Ethiopia who specializes in critical race theory - a rather important intersection these days.

 

 

 

when subtraction beats addition

The hammer and feather were released at the same time as a few million people watched back on Earth.  Absent air resistance, both objects fell to the lunar surface at the same rate.  David Scott had performed a version of the experiment Galileo Galilei is known for - the one your high school physics teacher said was true if you could ignore the air.

 

It turns out Galileo never dropped anything from the Leaning Tower of Pisa.   Instead he rolledballs of different masses down inclined planes.  The balls accelerated uniformly independent of their mass, but at a rate related to the angle of the plane.  He recognized their acceleration on a 90° ramp would be the same as dropping them from a tower.  One of his insights was if you get rid of friction and air resistance, the problem becomes simple.   This is one of the deepest insights in all of physics - that you can make seemingly ridiculous simplifications and get useful results. And once you know the idealized solution you can add in the fiddly bits that kept you from seeing things clearly at first. 

 

Physicists are trained to simplify wherever possible - (paraphrasing Einstein) just not too much. It's part of the art of the sport. It's so deeply engrained you find yourself using the approach in unrelated areas.  With this background I was struck by a piece in Nature showing people tend to add rather than subtract when solving problems.  It's very common.  Software can get overloaded with features in a hurry consider Microsoft Office.  It's fine to add some functionality over time.  The hard part is understanding something enough to subtract features to improve it's functionality takes serious creativity - in some areas it might be called taste.

 

Once the core ideas are understood it becomes possible to go much further. Before the scientific revolution of the 16^th and 17^th centuries Aristotle's teleological view of the world dominated Western thought.   An object's motion was determined by its nature and all processes were determined by goals.  It's a crude handwavy explanation that sort of makes sense if you don't ask too many questions.   Place a coffee cup around on your desk and give it a shove.  It moves for awhile and comes to a stop.   Everything in motion must constantly be moved by something. Galileo shattered this way of thinking and others built on it.  Newton came up with a good model for motion and gravity that still works well for most of what you and I do - you can and a probe on Mars and fly a helicopter there with it. .  About one hundred years ago Einstein, motivated by some foundational flaws in Newton's work, created "simple, but not too simple" theories that gave a much deeper view that solves a few thorny issues.  That helped to explode our view of the universe.  It also made global positioning systems work. 

 

With this deeper understanding of Nature our minds can travel to the most exotic places. Recently a visualization of a binary black hole system was released.  While the calculations are difficult, requiring a lot of supercomputer time, the core ideas are straightforward.  Enjoy the lightshow as the massive black holes warp nearby spacetime  (the notes are a good explainer)

 

There's much to be learned talking with people in very different fields.  Some are motivated by simplicity, but their approaches are often different and enlightening. .  These people have a lot of skill and experience playing with their kind of simplification.  I'm thankful for conversations I've had with some of you where you've been open enough to let me learn a bit from you.  It's sharpened my approach.

 

 

looking at the algorithmic economy

minipost

If you think about how society and the Internet, you probably know about Joan Donovan of Harvard's Shorenstein Center.  Among other things she's known for rejecting the notion of the "attention economy" as being somewhat gas lighting.  Instead she uses the phrase "algorithmic economy."

Andy Revkin of Columbia interviewed her this past Friday as part of his Sustain What series.  She talks about the possibility of a path to a public interest Internet while safeguarding speech.  Also how disinformation memes develop and need to be watched and how the current control of interests on the Internet fail.   You may or may not agree with her, but she's one of the deeper thinkers in this area and this is a particularly clear introduction to what she's about.  Andy does a great interview job, pushing back here and there to go deeper.  An excellent way to spend an hour.

getting down to the bedrock

Some areas are built on foundations of fundamental principals that can be built upon.  For example many of the world's religions have a form of the golden rule in their bedrock.  Physics has a few of these cornerstones that are so deep they're considered beautiful and have become guides.  I've been thinking about one of them - complementarity -  a lot recently.  Particularly as it appears outside of physics in many areas probably including some you're used to thinking about.

 

Neils Bohr and Albert Einstein were contemporaries - peers actually.  Both were great sources of quotes.  Einstein's fame is such that it's difficult to figure out exactly what he did say without original sources. Bohr's lack of fame outside of physics makes it easier. Here are a few:

 

“We are all agreed that your theory is crazy. The question which divides us is whether it is crazy enough to have a chance of being correct. My own feeling is that it is not crazy enough.”

“Never express yourself more clearly than you are able to think”

“A physicist is just an atom's way of looking at itself.”

“There are trivial truths and there are great truths. The opposite of a trivial truth is plainly false. The opposite of a great truth is also true.”

 

None were meant to be flippant and the last one is one of the richest quotes I know.  Really deep ideas have meanings that go beyond the surface.   As an example consider this question

 "is light a particle or a wave?"

 It turns out it's both, but sometimes it's most useful to describe it as a wave while other times you treat it as a particle.  It's impossible to apply both descriptions at the same time.   The essence of complementarity is there are different ways of looking at the world and each can have its own language and domain where it's true. 

 

You can step back a bit and look at a satellite in orbit.   Physics developed by Newton are good enough to put it there and predicting where it is to good precision, but if you're worried about the accuracy of its clock you need to bring in relativity.  Einstein and Newton offer very different theories that describe orbital motion and how clocks keep time.  Relatively turns out to be richer, but Newton's ideas are good enough for almost everything people normally do - that and I'd hate to describe the motion of a volleyball using special and general relativity.  

 

I won't go into quantum mechanics, but complementarity is at the core how you think about things.  That and like Newton and Einstein's models, there are boundaries where one is more useful than the other.  The trick is knowing both and where the boundary lies.  It's for another discussion, but I think complementarity is a good basis for talking about the concept of free will. 

 

Bohr was so taken with the idea of complementarity that he made it part of his coat of arms with a nod to Eastern religious philosophies and the Order of the Elephant.  (how's that for clickbait?)

 

Light offers another example. Newton used a prism to break whiteish sunlight into a spectrum of colors.  Later Keats objected to the beauty of science claiming Newton unwove the rainbow.  

Do not all charms fly/at the mere touch of cold philosophy?/There was an awful Rainbow once in heaven. 

 In reality something deeper is afoot.

 

 Consider a yellow light on your desk.  The wavelength of the light makes it look yellow, but if you are moving towards at a constant velocity you observe a shorter wavelength.  If you're moving fast enough it looks blue.  Faster still and it's ultraviolet.  If you're moving away the wavelength lengthens and it shifts towards the red.  In fact by selecting your velocity with respect to the light, the wavelength can be anything you want.   In this view of nature the color of light only depends on your velocity relative to it.   It may not seem useful, but it turns out to be one of the most important tools for measuring the size and age of the Universe. 

 

Complementarity appears all over physics and turns out to be a useful way of thinking about new phenomena.   Over time I've come to think of it in areas outside of physics.  The spoken word and a television show can both get across their own versions of something.  Neither is complete and understanding both can lead to a deeper appreciation.  Picasso and Rembrandt had very different portrait styles and both tell us something deep about their subjects in very different ways.  Mix different forms of art - a piece of music might describe the feeling of Winter quite differently from a painting, but both can offer deep if incomplete views of the feeling of the season.   Sports are offer many examples.  Movement in a sport can make statements that added with the emotion of the crowd give a more complete picture.

 

You can't use a flat Earth, geocentric universe, or being able to turn off gravity for an hour tomorrow.  The descriptions have to be valid in some domain  in the first place.  But having two good but very different representations of something in your head at the same time may just lead to a deeper understanding.  Usually you're not thinking about deep truths, but that's fine.  This doesn't come easily, at least not to me, but it's a lot of fun once you get the hang of it. 

 

 

questions inadequately probed

Kip sent this lovely piece 

 

 

It's pretty funny, but then you remember some misconceptions you had became you didn't ask the right questions.   When I was a kid we had to sing the Christmas carol Angels We Have heard on High.   Apart from the line  Gloria in excelsis Deo,  it made sense.  Our teacher didn't explain it was Latin, so my mind patched together a meaningless phrase that I could sing out out - something like in eggshells sustain -e-oh.   A few years later we had to sing it in a choir -  this time with a score.  I didn't know Latin, but at least there was enough information to track it down. 

 

Keeping with the family tradition one of my nieces proudly sang the line:  The ants are my friends, they’re blowing in the wind. The ants they’re a blowing in the wind.  (I wish I could remember her full take on the song - she was about four)

 

The mind is awfully good at coming up with an explanation when you don't have enough information, I've had several other dramatic misunderstandings - often much more serious than the lyrics in a song.  Over the years you learn you need to ask questions when there's cognitive dissonance.  Not that this works for all misinterpretations and misinformation, but it helps for some.  

 

Feel free to add some of yours in the comments.