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The Spinning Magnet: The Electromagnetic…

The Spinning Magnet: The Electromagnetic Force That Created the Modern… (édition 2018)

par Alanna Mitchell (Auteur)

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"A cataclysmic planetary phenomenon is gathering force deep within the Earth. The magnetic North Pole will eventually trade places with the South Pole. Satellite evidence suggests to some scientists that the move has already begun, but most still think it won't happen for many decades. All agree that it has happened many times before and will happen again. But this time it will be different. It will be a very bad day for modern civilization."… (plus d'informations)
Titre:The Spinning Magnet: The Electromagnetic Force That Created the Modern World--and Could Destroy It
Auteurs:Alanna Mitchell (Auteur)
Info:Dutton (2018), 336 pages
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The Spinning Magnet: The Electromagnetic Force That Created the Modern World--and Could Destroy It par Alanna Mitchell


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Maybe this one was just up my alley in all the right ways or maybe the author is pretty spot-on with her mix of science history, humanization of the players, and just the right dose of scientific explanation for laymen.

Maybe it was both.

Regardless, I seriously enjoyed this non-fiction all about magnetism. It shouldn't come as all that much surprise that it has serious biological roots and it's all about physics and chemistry, but the author balances everything in such a way that it's always interesting. I didn't realize that magnetism was under controversy back in the days of Galileo. The way that it all ties seamlessly into geology should also be obvious, but I never felt uncomfortable in the writing. Indeed, I was pretty much uniformly fascinated.

The big zinger about the poles reversing and the effects on modern society aren't sensationalized, either. There's a big "I Don't Know" in there, but so much of the evidence points to a protracted (say a few thousand years) time of less magnetic shielding as the poles do their thing. The fact they will flip is not in doubt. The fact that we might be undergoing a radical influx of harmful radiation because the Earth isn't going to be blocking solar storms is probably the scariest thing I can imagine.

That's even worse than losing all our electronics. I mean, that's bad enough and I'll have to go buy a bedpan and a shotgun to defend myself in my new dystopian nightmare, but we're talking about a mass-extinction event. Well, assuming we or the animals don't start breeding for rad-tolerant biologies or take rad-x.

Can you imagine a bunch of teens running around with early onset dementia?

Oh, wait, yeah. I've read quite a few YA novels.

Really fascinating non-fiction, here! It's right up there with some of the very best non-technical popular science books I've read! (That's saying a bit. I like good science books. :)

Thanks to Netgalley for the ARC!

( )
  bradleyhorner | Jun 1, 2020 |
I am a bit conflicted when it comes to reviewing a book by someone who does not have expertise in the field. A lot of popular science writers make a living out of producing books on subjects where they are non-experts. (Well at least initially). I guess, they can approach the subject without any pre-conceptions or commitments to particular schools of thought and that is an advantage where there are often multiple competing theories. Assuming that they are intelligent information hounds they can also question all the acknowledged experts in the field and draw on their knowledge...and hopefully, ask some of the tough questions that the experts might be trying to avoid. And finally, a good writer can usually put together a readable book. Though this one follows the well worn formula of personal anecdote (maybe with a bit of the flavour of the eccentric scientist she is interviewing) then into the science ...or often history in this case. Mitchell traces the development of knowledge about magnets and the earth's magnetic field from the very beginnings though until the present. Along the way we are treated to the intriguing story of magnetism in rocks and reversals of magnetism and how the magnetism in rocks let to the gradual adoption of the drifting continents theory. (although not without huge opposition). William Gilbert put it rather well when he said that he would be..."dammed and torn to pieces by the maledictions of those who are either sworn to the opinions of other men, or are foolish, corruptors of good arts,learned idiots, grammatists, sophists, wranglers , and perverse little folk"....And sure enough the Jesuits led the attack. "Heliocentism was ...monstrous. According to contemporary (around 1600AD) interpretations of the bible, the earth was the core of God's creation . This meant that everything else had to revolve around it.To claim anything else was was to claim that the Bible was wrong . Heresy".

Hard to fight against these sorts of ideas. They were pretty resistant to evidence and reason or common sense. And quick to burn people at the stake to make their point about "wrong belief". Interesting how it was so often those doing the burning who were wrong. Seems like justice was in rather short supply and one wonders what a just god was doing about this sort of activity.
And it wasn't just the clerics who hounded unorthodox belief. P 186 has a nice little vignette about poor Alfred Wegener..who came up with the idea (in 1915) that the continents actually drifted apart ...he was ostracised and unable to find work at a university in his home country...he died trapped in a storm ...when he was 50 and long before he was vindicated. It was not until the 1950's that vindication came. (I recall my high school Geographer teacher commenting the he believed in the Continental Drift theory ..this was about 1959. And he obviously felt he was being quite radical.
Cambridge's Sir Edward Bullard, one of the British lions of geophysics, who first repudiated Wegener's ideas and then championed them, wrote about the backlash in a retrospective essay in the 1970's. "There is always a strong inclination for a body of professionals to oppose an unorthodox view. Such a group has a considerable investment in orthodoxy: They have learned to interpret a large body of data in terms of the old view, and they have prepared lectures and perhaps written books with the old background. To think the whole subject through again when one is no longer young is not easy and involves admitting a partially misspent youth". This is undoubtedly true but perhaps a kinder, more tolerant view of unorthodoxies might also be warranted rather than the savage burnings and public excoriations felt out to people like Giodorno Bruno and Wegener.

I do like the way that Mitchell tracks down some of the historic places and historic documents . I find that quite fascinating and it certainly adds interest to her tale.
And I did find her summary of electromagnetism quite riveting. P 102: "A stationary charged particle makes an electric field but not a magnetic one. A moving charged particle makes an electrical field and an electrical current, which makes a magnetic field. That can mean a bunch of moving charged particles in a current, or it can be the spin of an electron within an atom.You can take the idea down to the scale of a single atom of iron. Its negatively charged, unpaired electrons are creating a tiny magnetic field. If you put enough of these atoms together so that the tiny magnetic fields arrange themselves to amplify one another instead of cancelling each other out, you get a magnetic substance". There seems to me to be hints there of the particle-wave duality. (If it doesn't's a point with an electric charge....but if it moves then it behaves as waves (electrical and magnetic)). And movement implies space and time changes...and there are serious problems with the space-time concepts.

As she says: "Albert Einstein realised that what constitutes "movement" here depends on one's frame of reference If you are at rest with respect to an electrical charge, you will see an electrical field. If you are moving with respect to the same electrical charge, you will see a moving charge which is producing an electrical current as well as a magnetic field. The same is true when you are stationary with respect to an electrical charge that is moving. It's all about perspective. It's all, as Einstein would say, relative".

The story ends....kind of....with Mitchell musing about another reversal of the poles. "When the poles revers and the earth's shield is weakened, some of that solar and galactic radiation will reach into the lower atmosphere and even parts of the surface".....and that will be very bad for humankind: acute radiation poisoning etc. Not so much a question of if it might happen but rather how soon it will happen?
Quite a nice book. Would it have made a difference if Mitchell was an expert? Probably. But then we would not have been able to detect the bias. It would have benefited from some diagrams and pictures. I give it 4 stars. ( )
  booktsunami | Mar 9, 2020 |
I really wanted to give this book at least 3 stars but just couldn't. I certainly learned something about magnetism and the Earth's magnetic field, I'll give you that. But, in my opinion, the book has some serious flaws.

The author tends to anthropomorphism to much. But this I mean, and I'm paraphrasing here, statements like "the electrons want to do this or that", "the earth and sun's magnetic fields frolic", the "conflict" between the inner and outer core. I read a lot of general science books and I'm sure other authors do this sort of thing but I don't remember it being so blatant as it is here.

The book could seriously use some diagrams. Some of these concepts are hard to visualize and visualization helps with understanding. Some diagrams depicting the magnetic lines of force around the planet, the Van Allen Belts, and a few others would have really helped.

The cover states "The electromagnetic force that created the modern world - AND COULD DESTROY IT". This is where the book really fails. She has a lot of information about the discovery of the earth's magnetic field and the relatively recent discovery that the field has reversed itself a number of times in the past. It's been 780,000 years since the last reversal, she mentions several times, leading us to think we're overdue. Maybe, but that wasn't clear. It sounds as if there is no real agreement on that among the scientists who study this. Some are worried, some are not. The magnetic field has apparently been weakening as long as it's been studied but we've only been studying it for a few hundred years and the field has been around for billions of years. There's just no way of knowing if what we're seeing is just normal fluctuations (at least as far as I could tell from this book) or if it means the field is going to reverse tomorrow.

Is there a way to prepare for a field reversal? Don't know from here. It's been hard enough to get governments interested in global climate change, which has near universal acceptance among scientists. And what might happen to us? More cancer? Disruptions in communications? The end of FaceBook? The end of civilization? Hard to tell.

This part of the book bothered me the most, mainly due to the tease on the cover. 80% of the book is leading up to the question of field reversal and the payoff was meager. ( )
  capewood | Jun 10, 2018 |
With all the talk of climate change, the sixth extinction, the collision of galaxies and the death of the sun, Alanna Mitchell adds another – the fading of our magnetic field. We are protected from the sun’s ferocity by a magnetic field that comes from the core of the planet. The sun can blow it back, but it can’t blow it away. Worryingly, all is not well with that shield.

The Spinning Magnet is almost entirely history. Mitchell looks at the long list of milestones as we discovered and tried to understand electricity and magnetism. There are as many wrong turns as right ones, but today we have a good idea of what came before (though no feel for what comes next). The most important discovery was that electricity and magnetism are both manifestations of the same force. We ignore one for the other at our peril. By 1838 we knew the magnetic field came from the center of the Earth. We’ve spend the following 200 years taking measurements everywhere, all the time, to figure out the patterns, the intensity, the movements and the implications. But that’s also how we know it is fading.

The magnetic north and south poles used to reverse fairly regularly, and they leave traces when they do. There hasn’t been one since we came along, so we don’t know what to expect. But reversing the poles and the field will almost certainly wreak havoc like we’ve never seen. For one thing, we now run on electricity. When extraordinary solar flares penetrated the field in the mid 1800s, batteries powering the telegraph network all over the western world caught fire, seemingly spontaneously. Disconnecting them did not shut the system down, however. It ran on “celestial power”. Today, everything is electric. But in addition, everything runs on magnetic media. All the software, hard drives and memory banks in the world might be wiped if the magnetic field behaves badly. It could be like Puerto Rico after Hurricane Maria, but with no possibility of aid, as nothing would work anywhere. And that doesn’t count what it might do living beings. Birds for example, can actually see the magnetic field, and use it to navigate thousands of miles twice a year. Many insects use it too. We have no idea how they will handle a reversal. If the field doesn’t reverse but fades away, the sun will be free to fry the Earth into another Mercury, and continually bombard it with killer radiation (which is why “escaping” to Mars is no solution. Its magnetic field is long gone). It gives one pause.

Mitchell’s style is fast and spare. Her book is very easy to read. The sentences are short, direct and declarative. The chapters are short and concise. They are discrete entities, each having its own tight purpose. She avoids the worst complexities. It is page 96 before Mitchell uses the word quantum. And it only appears once more later. That’s pretty remarkable for a book on atomic structures and processes.

The irony is that our discovery of electricity, magnetism and how to employ them has allowed us to understand that life as we know it could end with the change or demise of the magnetic field and all the wonderful ways we have deployed electricity and magnetism.

David Wineberg ( )
  DavidWineberg | Oct 20, 2017 |
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"A cataclysmic planetary phenomenon is gathering force deep within the Earth. The magnetic North Pole will eventually trade places with the South Pole. Satellite evidence suggests to some scientists that the move has already begun, but most still think it won't happen for many decades. All agree that it has happened many times before and will happen again. But this time it will be different. It will be a very bad day for modern civilization."

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