The Scientific Problem That Must Be Experienced
To understand turbulence we need the intuitive perspective of art.
When the German physicist Arnold Sommerfeld assigned his most brilliant student a subject for his doctoral thesis in 1923, he admitted that “I would not have proposed a topic of this difficulty to any of my other pupils.” Those others included such geniuses as Wolfgang Pauli and Hans Bethe, yet for Sommerfeld the only one who was up to the challenge of this subject was Werner Heisenberg.
Heisenberg went on to be a key founder of quantum theory and was awarded the 1932 Nobel Prize in physics. He developed one of the first mathematical descriptions of this new and revolutionary discipline, discovered the uncertainty principle, and together with Niels Bohr engineered the “Copenhagen interpretation” of quantum theory, to which many physicists still adhere today.
The subject of Heisenberg’s doctoral dissertation, however, wasn’t quantum physics. It was harder than that. The 59-page calculation that he submitted to the faculty of the University of Munich in 1923 was titled “On the stability and turbulence of fluid flow.”
Sommerfeld had been contacted by the Isar Company of Munich, which was contracted to prevent the Isar River from flooding by building up its banks. The company wanted to know at what point the river flow changed from being smooth (the technical term is “laminar”) to being turbulent, beset with eddies. That question requires some understanding of what turbulence is. Heisenberg’s work on the problem was impressive—he solved the mathematical equations of flow at the point of the laminar-to-turbulent change—and it stimulated ideas for decades afterward. But he didn’t really crack it—he couldn’t construct a comprehensive theory of turbulence.
Heisenberg was not given to modesty, but it seems he had no illusions about his achievements here. One popular story goes that he once said, “When I meet God, I am going to ask him two questions. Why relativity? And why turbulence? I really believe he will have an answer for the first.”
It is probably an apocryphal tale. The same remark has been attributed to at least one other person: The British mathematician and expert on fluid flow, Horace Lamb, is said to have hoped that God might enlighten him on quantum electrodynamics and turbulence, saying that “about the former I am rather optimistic.”
STARRY, STARRY MATH: Vincent van
Gogh’s Starry Night offers a gripping way to visualize a hidden
regularity of
turbulence, a constant mathematical relationship between
points, later discovered by Soviet physicist Andrei Kolmogorov.
You get the point: turbulence, a ubiquitous and eminently practical problem in the real world, is frighteningly hard to understand. Nearly a century after Heisenberg, scientists are still trying to figure it out. And it’s still a cutting-edge problem: Russian mathematician Yakov Sinai won the 2014 Abel Prize for mathematics—often seen as the Nobel of math—partly for his work on turbulence and chaotic flow........MUCH MORE
Here's that July 1, 2019 post:
World Class Fisheries: Our Friend The Cod (and an amazing bit of research)
Starting about fifteen years ago there were signs that Atlantic cod were heading north and invading the territory of their polar cousins, which may, or may not, be a harbinger of changes brought about by anthropogenic global warming.
The attribution studies are still too simplistic, compared to the systems they are trying to correlate, to be of much use to policy makers.
If done correctly, the interactions in this kind of study, between the atmosphere, sea-surface, deep sea and biology become mind-boggling very shortly after you turn your supercomputer on.
One, just one factor that goes into figuring out what is going on, turbulence, is called the "oldest unsolved problem in physics" and it is but one factor in the complex-chaotic systems - and their interactions - that you are trying to understand. We'll have more on that after the jump.
And we'll have more on fishies and global warming later in the summer.
First though, a survey paper put together by a Korean high-schooler which, if he is at all representative of the Korean education system pretty much tells the rest of the world, even the vaunted Finnish schools, that we are doing it wrong.
One quick note, the school has an English-only policy during the school day, which is helpful for folks who don't speak Korean....MUCH MORE
Also 2012's: Turbulence
