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Archive for the ‘Physics’ Category

the-universe-in-100-key-discoveries-by-giles-sparrowThe Universe in 100 Key Discoveries, Giles Sparrow (Quercus 2012)

Possibly the best book I’ve ever read on astronomy: text and images complement each other perfectly. Even the solidness of the book was right. It’s a heavy book about heavy ideas, from the beginning of the universe to its possible endings, with everything astronomical in between.

And everything is astronomical, if it’s looked at right. The elements vital for life were cooked in stars before being blasted out by supernovae. We are star-stuff that has the unique privilege – so far as we know – of being able to understand stars.

Or trying to. This book was first published in 2012, so it’s inevitably out of date, but many of the mysteries it describes are still there. And when mysteries are solved, they sometimes create new ones. Even the behaviour and composition of a celestial body as close as the Moon is still impossible for us to explain. But sometimes it’s easier at a distance: the interior of the earth can harder to study than galaxies millions of light years away, as I pointed out in “Heart of the Mother”.

In every case, however, understanding depends on mathematics. Astronomers have been building models of the heavens with shapes and numbers for millennia, but the models had to wait for two things to really become powerful: first, the invention of the telescope; second, the development of modern chemistry and physics. Whether or not there is life out there, celestial light is full of messages about the composition and movement of the stars and other bodies that generate it.

But visible light is only a small part of the electromagnetic spectrum and modern astronomy probes the universe at wavelengths far above and below it. The more data astronomers can gather, the more they can test the mathematical models they’ve built of the heavens. The best models make the most detailed predictions, inviting their own destruction by ugly facts. But when predictions fail, it sometimes means that the observations are faulty, not the models. Cosmological models predicted much more matter in the universe than we can see. Is the gap accounted for by so-called “dark matter”, which “simply doesn’t interact with light or other electromagnetic radiations at all”? (ch. 98, “Dark Matter”, pg. 396)

Dark matter is a strange concept; so is dark energy. Astronomy may get stranger still, but the cover of this book is a reminder that human beings inhabit two kinds of universe. One is the universe out there: matter and radiation, moons, planets, stars, galaxies, supernovae. The other is the universe in here, behind the eyes, between the ears and above the tongue. The cover of this book offers a vivid contrast between the swirling complexity and colour of a star-field and the sans-serif font of the title and author’s name. But the contrast is ironic too. The stars look complex and the font looks simple, but language is actually far more complex and difficult to understand than stars.

Consciousness may be far more complex still. In the end, is the value of science that it expands consciousness, offering new physical and mental sensations of discovery and understanding? The powerful and beautiful images and ideas in this book could only have been generated by science, because the universe is more inventive than we are. But without consciousness, the universe might as well not exist. Without language, we’d never be able to try and understand it. Then again, the universe seems to have invented language and consciousness too.

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restless-creatures-by-matt-wilkinsonRestless Creatures: The Story of Life in Ten Movements, Matt Wilkinson (Icon 2016)

A fascinating book about a fascinating thing: the movement of plants and animals. It’s also a very familiar thing, but it’s far more complex than we often realize. Human beings have been watching horses gallop for thousands of years, but until the nineteenth century no-one was sure what was happening:

The man usually credited for ushering in the modern study of locomotion is the brilliant photographer Eadweard Muybridge. […] His locomotory calling came in 1872, when railroad tycoon and former California governor Leland Stanford invited him to his stock farm in Palo Alto, supposedly to settle a $25,000 bet that a horse periodically becomes airborne when galloping. (ch. 1, “Just Put One Foot in Front of Another”, pg. 16)

To answer the question, Muybridge used a series of still cameras triggered by trip-wires. And yes, galloping horses do become airborne: “not when the legs were at full stretch, as many had supposed, but when the forelimbs and hindlimbs were at their closest approach.” However, Matt Wilkinson calls another man “the true founding father of the science of locomotion”: the French scientist Étienne-Jules Marey, who had been investigating movement using a stylograph. In fact, it was Marey who first proved that galloping horses become airborne (ch. 1, pg. 19). Muybridge’s photographs were dramatic confirmation and the two men began to collaborate.

Marey also pioneered electromyography, or the recording of the electrical impulses generated by moving muscles. Like the rest of modern science, biokinesiology, as the study of animal movement might be called, depends on instruments that supplement or enhance our fallible senses. It also depends on mathematics: there is a lot of physics in this book. You can’t understand walking, flying or swimming without it. Walking is the most mundane, but also in some ways the most interesting, at least in its human form. Bipedalism isn’t an everyday word, but it’s an everyday sight.

What does it involve? How did it evolve? And how important was it in making us human? Wilkinson looks at all these questions and you’ll suddenly start seeing your legs and feet in a different way. What wonders of bioengineering they are! And what a lot of things happen in the simple process of “just putting one foot in front of another”. Scientists still don’t understand these things properly: for example, they can’t say whether or not sport shoes are dangerous, “lulling us into a false sense of security, causing us to pass dreadful shocks up our legs and spine without our being aware of them” (ch. 1, pg. 29).

But there’s much more here than horse and human locomotion: Wilkinson discusses everything from eels, whales, pterodactyls, bats and cheetahs to amoebas, annelid worms, fruit-flies, zombified ants and the “gliding seed of the Javan cucumber Alsomitra macrocarpa”. He also discusses the nervous systems, genes and evolution behind all those different kinds of movement. This book is both fascinating and fun, but I have one criticism: its prose doesn’t always move as lightly and gracefully as some of its subjects do. Wilkinson mentions both Stephen Jay Gould and Richard Dawkins. I wish he’d written more like the latter and less like the former. If he had, a good book would have become even better.

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journey-to-the-centre-of-the-earth-by-david-whitehouseJourney to the Centre of the Earth: A Scientific Exploration into the Heart of Our Planet, David Whitehouse (Weidenfeld & Nicolson 2015)

Can you touch anywhere on your body with your right hand? Replying quickly, you might say you can. But what about your right elbow? You can’t touch that with your right hand. Science is like that, because distant things are often easier to study and understand than close things. We have a good understanding of how stars work, for example, but not of how the earth’s magnetic field is generated.

And while we’ve been able to predict solar eclipses for millennia, we still can’t predict earthquakes or volcanic eruptions. Understanding the deep earth is difficult, so there are a lot of mysteries and conjectures in this well-written and compelling book about the interior of our home planet. Scientists have landed probes on Mars, millions of kilometres away, but the “deepest hole ever drilled on earth – the Kola Superdeep borehole in northern Russia” reached only 12,262 metres. That’s a mere pinprick by comparison with the radius of the earth. To get beyond that, scientists have had to study the shockwaves generated by earthquakes. The medium is the message: as the waves pass through or hit different regions and materials, they behave in different ways.

For example, when the Croatian scientist Andrija Mohorovičić (1857-1936) “studied the records from several seismometers” after an earthquake near Zagreb, “he realised that some of the shockwaves […] were being reflected back to the surface from a boundary region between the crust and mantle.” (pg. 82 of the 2016 paperback) The region is now called the Mohorovičić discontinuity. But that discovery was made before the First World War and deep geology hasn’t advanced very much in the intervening century. This book borrows the title of a Jules Verne novel published in 1864. If Verne came back to life, he would be pleased to see that his work is still popular, but he would be disappointed to see that the human race was no nearer reaching the centre of the earth.

Or would he? The American geologist Don Anderson says: “Almost everything known or inferred about the inner core from seismology or indirect inference is controversial.” (pg. 211) Deep geology is a difficult science, but that’s part of what makes it so interesting. Something else that makes it interesting is that the inner earth can visit catastrophes on the outer earth and the film of the life that clings there:

The big question is: can we see mass extinction events on the way up? Some scientists believe that we can by looking for the plumes [i.e., giant plumes of rising magma]. Such a thing is seen in the south-west Pacific near the Fiji Tonga subduction zone. It’s 700 km deep, has a structure consistent with a massive temperature anomaly and may be rising. It could render the earth uninhabitable for humans and it will reach the surface in an estimated 200 million years. (ch. 17, “Plumes”, pg. 146)

Asteroid impact and gamma-ray bursts are not the only catastrophes that threaten the continued existence of the human race. They may not even be the most likely. The film of life on the surface of the earth is fragile and one day it won’t be there any more.

But there’s also life deep inside the earth, living in conditions of extreme pressure, heat and darkness. We still know little about this “deep biosphere” and it may hold some big surprises. The rest of the deep earth almost certainly does. And the deep earth is just the beginning: as Whitehouse describes in chapter 26, there are “Other Worlds, Other Journeys” to come, including the even more extreme conditions at the heart of Jupiter, where the temperature is a “staggering 37,000 degrees C” and the pressure is “over ten times that found at the centre of the Earth.” (pg. 239)

Or so scientists estimate. Will scanners be invented to prove their theories? Will probes ever get there and find out for real? We can hope so. In the meantime, this book is an excellent introduction to the ideas, the pioneers and the modern researchers into mysteries that are right beneath our doorsteps. Whether it’s discussing diamonds, demons or “Double-D-Prime”, Journey to the Centre of the Earth is popular science that’s interesting, entertaining and informative all at once.

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The Invention of Science by David WoottonThe Invention of Science: A New History of the Scientific Revolution, David Wootton (Allen Lane 2015)

I picked up this book expecting to start reading, then get bored, start skimming for interesting bits, and sooner or later give up. I didn’t. I read steadily from beginning to end, feeling educated, enlightened and even enthralled. This is intellectual history at nearly its best, as David Wootton sets out to prove what is, for some, a controversial thesis: that “Modern science was invented between 1572, when Tycho Brahe saw a new star, and 1704, when Newton published his Opticks” (introduction, pg. 1).

He does this in a clever and compelling way: by looking at the language used in science across Europe. If there was indeed a scientific revolution and science was indeed a new phenomenon, we should expect to see this reflected in language. Were old words given new meanings? Did new words and phrases appear for previously inexpressible concepts? They were and they did. “Scientist” itself is a new word, replacing earlier and less suitable words like “naturalist”, “physiologist”, “physician” and “virtuoso”. The word “science” is an example of an old word given a new meaning. In Latin, scientia meant “knowledge” or “field of learning”, from the verb scire, “to know”.

But it didn’t mean a systematic collective attempt to investigate and understand natural phenomena using experiments, hypotheses and sense-enhancing, evidence-gathering instruments. Science in that sense was something new, Wootton claims. He assembles a formidable array of texts and references to back his thesis, which is part of why this book is so enjoyable to read. As Wootton points out, the “Scientific Revolution has become almost invisible simply because it has been so astonishingly successful.” Quotations like this, from the English writer Joseph Glanvill, make it visible again:

And I doubt not but posterity will find many things, that are now but Rumors, verified into practical Realities. It may be some Ages hence, a voyage to the Southern unknown Tracts, yea possibly the Moon, will not be more strange then one to America. To them, that come after us, it may be as ordinary to buy a pair of wings to fly into remotest Regions; as now a pair of Boots to ride a Journey. And to conferr at the distance of the Indies by Sympathetick conveyances, may be as usual to future times, as to us in a litterary correspondence. (The Vanity of Dogmatizing, 1661)

Glanvill’s prescience is remarkable and he’s clearly writing in an age of pre-science or proto-science. He wasn’t just a powerful thinker, but a powerful writer too. So was Galileo and Wootton, who has written a biography of the great Italian, conveys his genius very clearly in The Invention of Science. You can feel some of the exhilaration of the intellectual adventure Galileo and other early scientists embarked on. They were like buccaneers sailing out from Aristotle’s Mediterranean into the huge Atlantic, with a new world before them.

Wootton also emphasizes the importance of Galileo’s original speciality:

The Scientific Revolution was, first and foremost, a revolt by the mathematicians against the authority of the philosophers. The philosophers controlled the university curriculum (as a university teacher, Galileo never taught anything but Ptolemaic astronomy), but the mathematicians had the patronage of princes and merchants, of soldiers and sailors. They won that patronage because they offered new applications of mathematics to the world. (Part 2, “Seeing is Believing”, ch. 5, “The Mathematization of the World”, pg. 209)

But there’s something unexpected in this part of the book: he describes “double-entry bookkeeping” as part of that mathematical revolt: “the process of abstraction it teaches is an essential precondition for the new science” (pg. 164).

He also has very interesting things to say about the influence of legal tradition on the development of science:

Just as facts moved out of the courtroom and into the laboratory, so evidence made the same move at around the same time; and, as part of the same process of constructing a new type of knowledge, morality moved from theology into the sciences. When it comes to evidence, the new science was not inventing new concepts, but re-cycling existing ones. (Part 3, “Making Knowledge”, ch. 11, “Evidence and Judgment”, pg. 412)

Science was something new, but it wasn’t an ideology ex nihilo. That isn’t possible for mere mortals and Wootton is very good at explaining what was adapted, what was overturned and what was lost. Chapter 13 is, appropriately enough, devoted to “The Disenchantment of the World”; the next chapter describes how “Knowledge is Power”. That’s in Part 3, “Birth of the Modern”, and Wootton wants this to be a modern book, rather than a post-modern one. He believes in objective reality and that science makes genuine discoveries about that reality.

But he fails to take account of some modern scientific discoveries. The Invention of Science is a work of history, sociology, philology, and philosophy. It doesn’t discuss human biology or the possibility that one of the essential preconditions of science was genetic. Modern science arose in a particular place, north-western Europe, at a particular time. Why? The Invention of Science doesn’t, in the deepest sense, address that question. It doesn’t talk about intelligence and psychology or the genetics that underlie them. It’s a work of history, not of bio-history or historical genetics.

In 2016, that isn’t a great failing. History of science hasn’t yet been revolutionized by science. But I would like to see the thesis of this book re-visited in the light of books like Gregory Clark’s A Farewell to Alms (2007), which argues that the Industrial Revolution in England had to be preceded by a eugenic revolution in which the intelligent and prudent outbred the stupid and feckless. The Invention of Science makes it clear that Galileo was both a genius and an intellectual adventurer. But why were there so many others like him in north-western Europe?

I hope that historians of science will soon be addressing that question using genetics and evolutionary theory. David Wootton can’t be criticized for not doing so here, because bio-history is very new and still controversial. And he may believe, like many of the post-modernists whom he criticizes, in the psychic unity of mankind. The Invention of Science has other and less excusable flaws, however. One of them is obvious even before you open its pages. Like Dame Edna Everage’s bridesmaid Madge Allsop, it is dressed in beige. The hardback I read does not have an inviting front cover and Wootton could surely have found something equally relevant, but more interesting and colourful.

After opening the book, you may find another flaw. Wootton’s prose is not painful, but it isn’t as graceful or pleasant to read as it could have been. This is both a pity and a puzzle, because he is very well-read in more languages than one: “We take facts so much for granted that it comes as a shock to learn that they are a modern invention. There is no word in classical Greek or Latin for a fact, and no way of translating the sentences above from the OED [Oxford English Dictionary] into those languages.” (Part 3, “Facts”, pg. 254)

He certainly knows what good prose looks like, because he quotes a lot of it. But his own lacks the kind of vigour and wit you can see in the words of, say, Walter Charleton:

[I]t hath been affirmed by many of the Ancients, and questioned by very few of the Moderns, that a Drum bottomed with a Woolfs skin, and headed with a Sheeps, will yeeld scarce any sound at all; nay more, that a Wolfs skin will in short time prey upon and consume a Sheeps skin, if they be layed neer together. And against this we need no other Defense than a downright appeal to Experience, whether both those Traditions deserve not to be listed among Popular Errors; and as well the Promoters, as Authors of them to be exiled the society of Philosophers: these as Traitors to truth by the plotting of manifest falsehoods; those as Ideots, for beleiving and admiring such fopperies, as smell of nothing but the Fable; and lye open to the contradiction of an easy and cheap Experiment. (Physiologia Epicuro-Gassendo-Charltoniana, 1654)

The Invention of Science is also too long: its message often rambles home rather than rams. If Wootton suffers from cacoethes scribendi, an insatiable itch to write, then I feel an itch to edit what he wrote. It’s good to pick up a solid book on a solid subject; it would be even better if everything in the book deserved to be there.

But if the book weren’t so good in some ways, I wouldn’t be complaining that it was less than good in others. In fact, I wouldn’t have finished it at all and I wouldn’t be heartily recommending it to anyone interested in science, history or linguistics. But I did and I am. The Invention of Science is an important book and an enjoyable read. I learned a lot from it and look forward to reading it again.

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Chaotic Fishponds and Mirror Universes by Richard ElwesChaotic Fishponds and Mirror Universes: the maths that governs our world, Richard Elwes (Quercus 2013)

Most popular introductions to maths cover well-trodden ground: the prime numbers, the square root of 2, the Fibonacci sequence, Möbius strips, the Platonic polyhedra, and so on. Chaotic Fishponds and Mirror Universes covers some of those, but it lives up to the promise of its title and also talks about less familiar things: Voronoi tilings, Delaunay triangulation, neural networks, the simplex algorithm, discrete cosine functions, Pappus’s theorem, kinematic equations and the most effective ways to test blood samples for syphilis. Or coins for counterfeits.

Syphilis and counterfeits are both covered by the mathematics of group-testing, after all, but then maths covers everything. As Richard Elwes puts it: maths governs our world. He is good at explaining how and at demonstrating how it has, does and will shape the world. Some of the fields he discusses are very complex, so he can’t explain them properly in a popular introduction, but I couldn’t cope with a full explanation. It doesn’t matter: you don’t have to be able to climb Everest to be awed and enriched by the knowledge of its existence. Chaotic Fishponds and Mirror Universes is about what you might call hyperdimensional Himalayas: the mountains of maths and the men who climb them. The mountains rise for ever and contain everything that is, was or ever could be. Matter and energy are susceptible to mathematical modelling and may, in the final analysis, be maths, but maths is about much more. Richard Elwes is a mather placing a stethoscope to the heart not just of the world but of all possible worlds.

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Physics in Minutes by Giles SparrowPhysics in Minutes: 200 key concepts explained in an instant, Giles Sparrow (Quercus 2014)

In Borges’ story “The Book of Sand” (1975), the narrator acquires a heavy little book that has an infinite number of pages. When he opens it, he can never find the same page twice. The discrepancy between its finite size and its infinite contents begins to prey on his mind. He decides the book is a monstrous thing and wants to get rid of it: “I considered fire, but I feared that the burning of an infinite book might be similarly infinite, and suffocate the planet in smoke.”

It’s a good story, but the central idea doesn’t work, unless you assume magic is at work. A book with an infinite number of pages would be infinitely heavy. In fact, it would instantly become a black hole and start swallowing the universe.

So I assume, anyway. I’m interested in physics but I don’t know much about it. This book is aimed at people like me. It reminded me of Borges’ Book of Sand, partly because it’s small but heavy, partly because of the density of its ideas and the weight of history behind those ideas. Each page of explanation could easily become a hundred or a thousand: physics is daunting in its scope and complexity. Some of the greatest minds in history have put centuries of effort into understanding the behaviour of matter and energy.

That’s how we got astonishing things like electronics, X-rays and the atom bomb. Physics is an intellectual over-achiever, the super-star of the sciences, the most spectacular, powerful and difficult of all. But it’s the most difficult science because it’s also the simplest. Stars and steam-engines are much less complex than societies or brains, which is why you can’t get away with talking nonsense in physics. And although mathematics governs everything, it’s the simpler things – pendulums, light-rays, atoms, stars – that we can mathematize first.

Or some of us can, at least: the highly intelligent and obsessive men, like Galileo and Isaac Newton, who began modern physics by finding ways to extract abstract mathematics from concrete realities. If they’d tried to find maths in psychology or culture, they would have failed, because those things are too complex. They had to look at much simpler things like falling objects, planetary motion and light-rays. Galileo and Newton laid the foundations and later physicists have built on them, so that physics now towers into the scientific skies, the envy and awe of those working with more complex and intractable aspects of existence.

Giles Sparrow takes his readers on a tour of the tower. I suppose you could say he’s operating an express elevator, stopping briefly on the floors and offering a brief explanation of what it contains: elastic and inelastic collisions on one floor, fluid mechanics on another, mass spectrometry, electromagnetic induction and quantum electrodynamics on more. Then the doors snap shut and the elevator shoots up another floor. But one thing is found everywhere: mathematics. Sparrow quotes a lot of equations and uses a lot of numbers. If you want to understand physics, you have to know the maths. If you don’t, there’s no way to disguise your ignorance.

The maths is beyond me, so until brain-modification arrives I won’t be able to understand physics properly. Until then, this book is a good way of glimpsing the glories of the science. It’s also the closest you’ll get to handling Borges’ Book of Sand in real life.

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