Books: “How to Teach Relativity to Your Dog”
June 3, 2012
I still argue with the voice on my GSP. Don’t look at me that way: You do it, too! The voice has a British accent; we call her Petula. And I still argue when I want to stay on I-95 and she tries to send me onto US-1. But I do have a little more respect for her — or, at least, for the device — now that I’ve read Chad Orzel’s book “How to Teach Relativity to Your Dog.”
Orzel, a professor who also wrote “How to Teach Physics to your Dog,” explains in this more recent book that the technology of global positioning systems relies on a principle of the theories of relativity first formulated by Albert Einstein. A principle of the special theory of relativity holds that a clock that is in motion will “tick” increasingly more slowly as the speed of its motion increases. The general theory of relativity, on the other hand, holds that a clock runs faster the higher it is — that is, the greater its altitude in the gravitational field.
The atomic clocks aboard the GPS satellites speed up because of their altitude and slow down because of the speed at which the satellites orbit the earth. At the altitude of those satellites, the clocks are quickened more than they are slowed, but they are still keeping time at a different rate than clocks on the surface of the earth. Each satellite emits a radio signal with the time on its atomic clock. The GPS unit picks up two or three of those signals, calculates the difference between the time on the satellite clock and the time on the surface of the earth, and uses that information to determine the distance to each satellite and, from that, the location of the unit on the ground.
Pretty cool, huh?
Still, I don’t read about physics because I’m interested in the practical applications so much as because I’m interested in the theories and principles. It can be mind-bending stuff, but if given enough concentration and persistence, it can lead to some moments of enlightenment about how the universe works. And studying the theories of relativity, in particular, can be an eye-opening series of reminders that things are not always what they appear to be.
Orzel’s technique in this book is to explore the special and general theories of relativity, and some other matters, as though he were discussing them with his real-life dog, Emmy. This is the writer’s way of making the material more accessible to people like me, but frankly, it gets tiresome. The dog’s constant references to Orzel as “Dude” and the overworked jokes about Emmy’s appetite, disdain for cats, and fixation with chasing rabbits, grow old pretty quickly. And the premise crumbles as the dog begins to talk about physics as if she were a graduate student at Princeton.
I think anyone who picked up this book thinking that the dialogue with the dog, and the use of dog-world examples, would make physics easier to understand would be disappointed. Orzel’s explanations are clear, but he could have been just as clear without the input from the dog. More important, with or without the dog, a reader won’t get much out of this book without focusing attention on it, frequently stopping to think hard about what Orzel has just written, frequently re-reading paragraphs or whole sections and consulting the glossary at the back of the book.
Both the special and general theories of relativity depend on the idea that the laws of physics work the same for observers who are in motion and observers who are stationary, even though an event — such as a person dropping a ball from above his head to the floor at his feet on a moving train — will appear differently to the person dropping the ball and a person observing the event while standing still on the station platform.
An interesting thing that comes up again and again in Orzel’s book is the fact that researchers are still discovering implications of these theories that Einstein expounded at the beginning of the 20th century. Already Einstein’s work has led to the understanding that the mass of an object is a measure of its energy and the two properties are connected by the constant e=mc²; that time and space are expressions of the same thing; that gravity bends light; that large objects bend space; that a moving object shrinks in length in the direction in which it is moving — the faster it moves, the more it shrinks.
Orzel’s also discusses black holes, those concentrations of mass so dense that even light can’t escape their gravity; the principles behind nuclear energy — both the relatively weak energy that holds atoms together and the enormous energy that can power cities or destroy them; the discovery that the universe is expanding at a constantly increasing rate; and the likelihood that this expanding universe began as a single point that exploded in what we know call the “big bang.”
The dog? I can take or or leave her. But reading this book — some of it two or three times — was worth the energy (which, by the way, equals mass times the speed of light squared)
Em cee squared
May 17, 2010

A blackboard with formulas written by Albert Einstein, preserved in the Museum of the History of Science at the University of Oxford.
Several decades ago, I began to make a point of reading several books each year on subjects about which I knew little or nothing — including subjects that I found repulsive. Among those subjects have been mathematics and physics, both of which bedeviled me when I had to study them in high school and college. As I have mentioned here before, at least with respect to mathematics, I have derived a great deal of satisfaction from pondering these subjects when examinations and grades are not at issue, and I have found that those who claim that there is beauty and wonder in these fields are telling the truth
That background explains why I grabbed the opportunity to review a popular biography entitled “Einstein: The Life of a Genius” by Walter Isaacson. This is a coffee table book that contains a limited amount of text in proportion to the number pages and illustrates its points with many photographs and also with facsimiles of several letters and documents. Among these are Einstein’s letter to Franklin D. Roosevelt in which the scientist advised the president to call together a group of experts to study the possibility of developing an atom bomb — something Nazi Germany was known to be doing at the time. As it happened, Einstein — a pacifist whose work in physics helped pave the way to such weapons — was considered too great a security risk to work on the project himself, what with him being a native of Germany, a socialist, and a Jew.
Isaacson records that one of Einstein’s early physics instructors described him as “an extremely clever boy,” but added, “You have one great fault: You’ll never let yourself be told anything.” It wasn’t meant as compliment, but still, this tendency as much as anything else led to Einstein’s achievements in theoretical physics. Einstein — like Isaac Newton before him — would not accept anything as settled just because it was handed on to him by authoritative sources. He wondered and questioned and “experimented” with physical phenomena such as light and motion by forming images in his mind, and he changed the world.
Einstein is a curiosity in a way, because he was one of the most widely known celebrities of his time and his name is part of our language more than 50 years after his death, and yet most of us have little or no idea what he was up to. That doesn’t matter. He deserves his place in our culture if for no other reason than his persistence in questioning even his own conclusions.
Book Review: “Newton and the Counterfeiter”
February 19, 2010
I was working in the faculty room yesterday when one of the instructors asked the open air, “Does anyone know anything about Newtonian physics?” I told him his question was coincidental, because I had just finished reading a book about Isaac Newton, the 17th century physicist, mathematician, and natural philosopher.
I think I correctly answered my colleague’s question, which had to do with Newton’s Second Law of Motion: “A change in motion is proportional to the motive force impressed and takes place along the straight line in which that force is impressed.” But while the book I just read explained the achievements for which Newton is still regarded as one of the greatest of geniuses, its purpose is to recount the work of his later life, when he was warden of the Royal Mint — and particularly the relentless detective work with which he brought to justice Britain’s most brazen counterfeiter.
Newton did his signature scientific work at Trinity College in Cambridge, but he lobbied friends for many years to get him a political appointment in London. It finally came in the form of position at the mint, which made the silver coins that were Britain’s only hard currency at the time. When Newton arrived at his office in the Tower of London, the kingdom’s economy was on the verge of collapse, partly because of expensive military operations undertaken by William of Orange and partly because the royal currency was, in a word, disappearing. An old issue of coins was being degraded by so-called “clippers” who shaved bits of silver from the money to be melted down and sold. Meanwhile British silver was leaving the country altogether because it was worth more in exchange for gold in other countries than it was in exchange for commodities in England. The result was a bull market for counterfeiters, including the audacious and dangerous William Chaloner.
Newton’s predecessors as warden of the mint had not taken the job seriously except as a source of income, and that was expected of Newton, too. But he applied to the mint the same combination of energy and curiosity that had fueled his discoveries in fields like gravity and the behavior of light and his development of the mathematical system known as the calculus.
First, Newton took control of a program already underway when he arrived – the recall and replacement of all British coins then in circulation. This project was limping along when Newton took over, and he put the means in place to accelerate it and get the job done in a fraction of the projected time. Then he turned his attention to the counterfeiters, employing a network of spies and informers and counter-agents and double crossers to gather information and pounce on “coiners” – eventually including Chaloner, whose career as a counterfeiter had had its ups and downs.
Like most such scoundrels, Chaloner made his share of mistakes, and one of them was to publicly claim that the heart of the nation’s counterfeiting problem was in the mint itself, and imply that Newton’s incompetence was partly to blame. Don’t knock the Rock. Newton went after Chaloner with a vengeance, spending hundreds of hours personally interrogating people who could help build a case against the fraud. Chaloner had been in and out of prison several times and had dodged the noose that was reserved for counterfeiters, whom British law regarded as traitors. In Newton, he had met his match and – ultimately – his maker.
“Newton and the Counterfeiter,” both informative and entertaining, was written by Thomas Levenson, who is a professor of science writing at MIT.
A topic that Levenson discusses throughout this book – in fact, it’s an important thread that runs through all of Newton’s activities – is Newton’s search for contact with God. In fact, Levenson reports that religious matters became the preoccupation of Newton’s life when he had put most scientific inquiry behind him. I discussed that aspect of the book in a column in the Catholic Spirit, and it’s available at THIS LINK.
Warp speed and other diversions
July 2, 2009

BUSTER CRABBE as Flash Gordon
I once saw a cartoon panel taped to the wall outside a psych professor’s office at Kean University. A man of middle age was slumped in an easy chair in what seemed to be a state of depression. His wife stood over him, hands on her hips, and addressed him more or less as follows: “What I can’t understand is why you would read a book called ‘Oblivion and the Abyss’ in the first place!”
Well, I just got around to reading “Physics of the Impossible” by Michio Kaku, who is a theoretical physicist. In this book, which came out last year, Kaku discusses the possibility that various achievements that human beings have imagined and even tinkered with will become practical realities. We’re talking here about such things as teleportation, telepathy, time travel, invisibility, and visitations from “outer space,” concepts that have been the fodder of science fiction from Jules Verne to Flash Gordon to Star Trek.
I don’t know why I was disappointed; I think I already knew the overall thrust of what Kaku would say. Certain of these concepts – invisibility and teleportation, for example – are not contrary to the known laws of physics and may be achievable within a forseeable amount of time, where what is forseeable might be measured in hundreds of years. (I’m oversimplifying this.) Others, such as travel to other galaxies, are not contrary to the known laws of physics but are beyond the capabilities of a civilization of our rudimentary level of advancement. Still others — perpetual motion and travel into the past, for example — are contrary to the known laws of physics and impossible, period.

SATURN
Intellectually, I’m not surprised, but I’m disappointed nonetheless. I would rather have continued nursing the fantasy, born while I watched Flash Gordon and Doctor Zarkov matching wits with Ming the Merciless, that some day, somehow, I would board a space-going vessel and leave the gravitational pull of this planet, at least for a long weekend.
But Kaku has taken the wind out of my sails, if I may be allowed the metaphor, and I look with a twinge of melancholy at the images of Saturn and her moons being transmitted by the Cassini craft — and particularly the one in which Alpha Centauri gleams in the perpetual night sky far beyond the great planet’s rings (http://saturn.jpl.nasa.gov/index.cfm).

MING THE MERCILESS Charles Middleton
A friend of mine told me a couple of years ago that her employer had reserved a place for her on a voyage into space as soon as such a thing became available to consumers. That would have been all right as far as it went, but the trip envisioned would have been a little more than 300 miles each way. My ambition far exceeded that, and Kaku has made it clear that I was deluding myself.
Well, it was a relatively short time ago that some of the ideas that Kaku fools around with — such as an electron that can be in two places at the same time — were not only unknown but unimagined. So rather than put my vacation to Alpha Centauri out of my mind, I’ll put it on hold. After all, I’m only 66 years old. In the meantime, I still have to see the Grand Canyon.

CASSINI VIEW OF ALPHA CENTAURI OVER THE RINGS OF SATURN