Middle World


One of the traditional ways to explain a scientific subject is the historical approach: start at the beginning of the endeavor and explain why people asked the questions they did, how they answered them, and how each answer blossomed into new potential. It’s a popular way of teaching science, too, because it emphasizes the process that leads to new discovery. Middle World: The Restless Heart of Matter and Life(amzn/b&n/abe/pwll), by Mark Haw, exemplifies the technique. Not only is it effective, but this one slim book manages to begin with a simple, curious observation in 1827 and ends up synthesizing many of the major ideas of modern physics, chemistry, and biology!

That beginning is with Robert Brown, a botanist scrutinizing pollen grains dancing in a drop of water. He was hoping to discover how fertilization occurs in plants, but instead noted a physical phenomenon that would be posthumously named after him, Brownian motion. We learn that he set off on his voyage of discovery with a literal ocean voyage during the Napoleonic wars; that his ship fought off pirates shortly after setting sail; that he circumnavigated the Australian continent in a shabby, disintegrating ship, on a trip in which many of the crew died of malnutrition; and that he did all that to pull weeds, i.e. “botanize” for the Crown. That was an era of heroic science, and I have to confess that I did feel like a bit of a poseur after reading all that.

Brownian motion, though, was a mystery — one that was unexplained in Brown’s lifetime — and to many seemed to violate Newton’s laws. It wasn’t rule-like behavior — it was random and complex and didn’t fit into the conception of a clockwork universe that glided along on smooth trackways of causality and predictability. How to reconcile Newton with chance?

And then the book just takes off. We get Carnot, Thomson, and Clausius and an introduction to thermodynamics; Maxwell and Boltzmann and atoms and molecules; then the Miracle Year and Einstein’s hat trick, which included a theory of Brownian motion; Langevin and Perrin, the man who proved atoms. The entire revolution in physics is presented from the perspective of trying to explain a botanist’s observation of a few pollen grains. It works, too — it’s a beautiful summary of how science works, proceeding from question through trial and error testing to theory and refinement. The reconciliation with Newton requires an understanding of the Middle World, this broad domain between the atomic and the macroscopic, where behavior is in flux and the rules have to be explained in statistical terms — where cause has probabilistic, not hard and fast deterministic, effects.

In the 20th century, Haw tells us about the really cool stuff: modern chemistry and biochemistry, and how the behavior of the objects in the Middle World is central to understanding those processes. For example, he talks specifically about observations of kinesin, an important transport molecule in cells that you can see portrayed in this animation of activity in a cell as a two-legged stalk attached to a gigantic vesicle, making a stately march along a microtubule. Only in reality, a molecule’s progress is anything but steady and stately—it’s a wiggly jitterbug, buffeted by the soup of surrounding molecules, and it sometimes takes a step back, or two steps forward, or lurches and halts. Our “molecular machines” are not at all like the familiar ones in the macroworld, they are ruled by chaos and chance and all biochemistry does is skew the odds to get an average response in a particular direction, a tricky balancing act between randomness and order.

The final chapters explain that the study of the Middle World is not done. The next steps include new challenges, like nanotechnology and life itself.

It’s a phenomenal book. It’s slender and makes for an easy read, yet still it explains fundamental concepts well, in terms of the experiments that led to their discovery. There’s a reason we make biology students take physics and chemistry, and it’s because their essential ideas are all tightly interlinked — and this book makes a good case that viewing molecules as inhabitants of that Middle World is a powerfully unifying perspective.

Comments

  1. says

    ` I like historical viewpoints! That’s actually my favorite approach! I may actually read that book.
    ` …I may even write from a historical standpoint on my new soon to be scholarly blog (shameless plug – crosses fingers).

    ` BTW, what exactly is the Middle World (not to be confused with Middle Earth)? Isn’t that the world before Prometheus?

  2. says

    I am concerned and disappointed, PZ. I come here for atheism and liberalism and you rant about science. This is why I no longer come here, except for three or four times a day.

    Actually, you have made me add yet another book to the list of those I want to read. To hell with reconciling religion and science. Now we get to reconcile botany and piracy.

  3. Christian Burnham says

    Well, it doesn’t take an Einstein to work out what Brownian motion is caused by.

  4. says

    “Our “molecular machines” are not at all like the familiar ones in the macroworld, they are ruled by chaos and chance and all biochemistry does is skew the odds to get an average response in a particular direction, a tricky balancing act between randomness and order.”

    Nice!

  5. DaleP says

    Einstein used the mathematical theory of Brownian motion as “a way to indirectly confirm the existence of atoms and molecules.” (Wikipedia) His clear presentation was part of the final debate among physicists whether atoms were real and to estimate their size.

  6. Christian Burnham says

    DaleP: Then maybe I should have said that it doesn’t take an Einstein to work out gravity.

  7. Abbie says

    As a layperson with a lay interest in lay science I’ve read a number books with that historical perspective… “Big Bang” and “Empire of Light” are two good examples.

  8. mgarelick says

    Is “Middle World” the one we live in — between atomic world and galaxy (universe) world?

  9. Christian Burnham says

    mgarelick: From its Amazon page:

    Between the microscopic world of quarks and atoms, and the macroscopic one of pebbles, planets, and galaxies there is another world, strangely neglected by science since Isaac Newton.

    To be honest- I’m not sure middle world is that neglected given that Paris Hilton, the iPhone and Las Vegas all fit the above criteria (bigger than a quark, smaller than a galaxy). I myself tend to spend quite a bit of time inbetween those two size-ranges. Maybe I should write a book about my travels in middle world.

  10. Bobby says

    “it’s a beautiful summary of how science works, proceeding from question through trial and error testing to theory and refinement.”

    Just like Intelligent Design?

  11. Eric TF Bat says

    @Bobby: Intelligent Design lacks the “testing” and the “refinement” parts, but otherwise, yes.

  12. Bobby says

    >>> it’s a beautiful summary of how science works,
    >>> proceeding from question through trial and error
    >>> testing to theory and refinement
    >>
    >> Just like Intelligent Design?
    >
    > Intelligent Design lacks the “testing” and the
    > “refinement” parts, but otherwise, yes.

    It also lacks the “question”, “trial and error”, and “theory” parts, unless the question is “How can we sneak our religious beliefs past the courts”, the theory is “You can fool most of the people all of the time”, and the trial and error is the ever-evolving spin put on creationism in attempts to make people confuse it with science.

  13. cm says

    Christian Burnham “Between the microscopic world of quarks and atoms, and the macroscopic one of pebbles, planets, and galaxies there is another world, strangely neglected by science since Isaac Newton.”

    To be honest- I’m not sure middle world is that neglected given that Paris Hilton, the iPhone and Las Vegas all fit the above criteria (bigger than a quark, smaller than a galaxy)

    No, Paris, iPhone, and Vegas are in the macroworld of pebbles planets and galaxies. “Middle world”, if I gather correctly, must mean molecules. Small but not quantum small.

  14. cm says

    This middle world stuff puts me in the mind of an old favorite sketch from SNL:

    The World of Discover! with Peter Graves:

  15. Mike Kinsella says

    Ah for the days of heroic science! I know exactly how you felt- I felt like a poseur too when I first read of Darwin’s adventures during the voyage of the Beagle…Thanks for the review; I’ll put it on my must read list.

  16. Ian H Spedding FCD says

    Bobby wrote:

    It also lacks the “question”, “trial and error”, and “theory” parts, unless the question is “How can we sneak our religious beliefs past the courts”, the theory is “You can fool most of the people all of the time”, and the trial and error is the ever-evolving spin put on creationism in attempts to make people confuse it with science.

    As someone said, the only trial and error in Intelligent Design is the error they made in going to trial in Dover in the first place.

  17. Luna_the_cat says

    Excellent. And bad, too, because now I have yet another book on my reading list.

  18. Azkyroth says

    Our “molecular machines” are not at all like the familiar ones in the macroworld, they are ruled by chaos and chance and all biochemistry does is skew the odds to get an average response in a particular direction, a tricky balancing act between randomness and order.

    That’s funny; the same description more or less fits a lot of the machinery I work with. ;/

    [Insert predictable potshot at Windows here]

  19. hoary puccoon says

    I was once on an archaeological expedition on a remote Greek island when high winds prevented the supply boat from landing. My husband and the island caretaker had to go out and shoot a wild goat to feed us. It was sort of, if you squinted, a little heroic. Nobody died of malnutrition, though. I have just got to get Haw’s book.

  20. Paul Schofield says

    Man, just from that description I can see a dozen more jumping off points.

    For example, the kinesin ‘walk’ is often studied using optical tweezers, which are a nice illustration of several critical optical principles, as well as concepts of momentum and similar mechanics. The same tweezers are used in experiments that involve manipulations that go right down to single molecules. One of the more interesting ones involved stretching DNA to reveal a whole new form.

    I believe that all that fits nicely in the middle world regime. The optical tweezers effect in particular is an utterly counter-intuitive and strange result of optics and mechanics acting in an unfamiliar scale.

  21. ShavenYak says

    Einstein essentially got his Nobel prize for discovering how tea works.

    No, Einstein got his Nobel “for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect.” I suppose discovering how tea works is part of his services to theoretical physics, but I think the photoelectric effect was more important in getting him the prize.

    But I’m just a silly American, so I’m sure I’m underestimating the importance of tea.

  22. SLC says

    Re middle world

    Richard Dawkins has an entire chapter in his book, “The God Delusion,” discussing the concept of middle world as it relates to the very large and the very small.

  23. stogoe says

    per SLC, Dawkins used the term Middle World, but to refer to the world of stuff about the size of humans. Haw seems to be using Middle World to refer to molecule-sized things.

  24. Bruce says

    Brownian Motion inside Diatom 1000x here. -386sx

    THAT’S Brownian motion? I thought cells had little outboard motors and factories with whistles for the lunch break. I’m very disappointed.

  25. says

    There’s a reason we make biology students take physics and chemistry, and it’s because their essential ideas are all tightly interlinked

    It’s a good reason too. I enjoyed biology much more after organic chemistry because it made a lot more sense.

  26. says

    I think part of why Brownian motion was so puzzling for a while is that people had no real idea how small the ultrasmall (even, say, large molecules) are. Even today, one can boggle at the idea that there are 1024 molecules of water in a glass.

    And the “middle world” is hardly neglected – that’s what chemists deal with all the time!

  27. says

    There used to be a great science TV series based on this kind of principle.

    It always started with a random factoid, then went into some scientific discovery, and worked it’s way back to the seemingly random factoid….

    I think it was produced by the BBC…late 80s, early 90s maybe? Maybe even early 80s. Anyone know what I’m thinking of?? Can’t for the life of me come up with a name…..

    Cheers.

  28. tony says

    Re: Avogadro’s number……

    My Son & I were talking about ‘how many molecules’ and ‘how small are they really’… and used the following analogy…

    the number of molecules in a 300cl glass of water is about 1025 (avogadro * 300 / 18 (molar weight))

    the earth has a volume of about 1021 cubic meters = 1027 cc.

    a golf ball has a volume of about 100 cc.

    therefore: there are approx 1025golf balls in a volume the size of the earth! (10^27 / 10^2 = 10^25)

    So, if a molecule was the size of a golf ball…. the glass would need to be the size of the earth to hold all the molecules.

    response: whoa!

  29. tony says

    sorry — a golf ball has a cubic volume of approx 100cc (it’s in a box about 4.65 per face dimension; holding the golf ball with diameter 4.3 cm)

    It’s an approximation…. ok?