Tag Archives: Quantum physics

EVENT – 2013-07-04 Computing with Quantum Cats – John Gribbin – London

Posted on by
Reply

When - 4 July 2013, 7pm

Where - Royal Institution, London

The quantum computer is no longer the stuff of science fiction. Pioneering physicists are on the brink of unlocking a new quantum universe which provides a better representation of reality than our everyday experiences and common sense ever could. The birth of quantum computers – which, like Schrödinger’s famous ‘dead and alive’ cat, rely on entities like electrons, photons or atoms existing in two states at the same time – is set to turn the computing world on its head.

John Gribbin gives an account of the the nature of quantum reality, arguing for a universe of many parallel worlds where ‘everything is real’. Looking back to Alan Turing’s work on the Enigma machine and the first electronic computer, John explains how quantum theory developed to make quantum computers work in practice as well as in principle. He takes us beyond the arena of theoretical physics to explore their practical applications – from machines which learn through ‘intuition’ and trial and error to unhackable laptops and smartphones. And he investigates the potential for this extraordinary science to create a world where communication occurs faster than light and teleportation is possible.

Tickets: £10. Booking essential – see website.

Time Reborn – Lee Smolin *****

Posted on by
2

As I write this we are a third of the way through 2013 (time is important here) and I can say with hand on heart this is the best popular science book I have read all year.

Screenshot_30_04_2013_09_28Lee Smolin’s book is largely accessible (more on this later) and simply mind-boggling in its scope. What he does here is take on time, and specifically the position of time in physics. Even taken as a simple book on time this is brilliant. The fact is, the majority of books that claim to be about time tell you nothing. It’s striking that A Brief History of Time tells us that amongst a list of deep scientific questions that have answers suggested by ‘Recent breakthroughs in physics, made possible in part by fantastic new technologies’, is ‘What is the nature of time?’ But you can search the book from end to end for any suggestion of what time is or how it works. There is plenty on how we observe time, and how interaction with matter can change these observations, but nothing deeper.

Smolin gives what is, for me, the best analysis of the nature of time from a physics viewpoint in a popular science book I have ever seen. He goes on to describe how most physicists consider that ‘time does not exist’, and comes up with an approach where time becomes real in physics. Now I do have one issue with Smolin here. He says that amongst his non-scientific friends ‘the idea that time is an illusion is a… commonplace.’ This is garbage (or at least his friends are non-representative). The vast majority of people who aren’t physicists or philosophers would say ‘Of course time exists.’ However, Smolin sets off to first persuade us it doesn’t, using the most common arguments of current physics, and then to show how this is a mistake.

In fact, I think the reason most people wouldn’t agree is because it isn’t really true that modern physics says time doesn’t exist. What it says is that the idea of time as a moving present that heads from the past into the future isn’t real, and that there are plenty of concepts in physics like natural laws that appear to be outside of time, and so time isn’t as fundamental as people think. Nor, relativity shows us, is it absolute. This isn’t the same as something not existing or being an illusion, and I think the physicists who use this label have spent too much time talking to philosophers. Dogs aren’t fundamental to the laws of physics, but this doesn’t mean they don’t exist.

Nonetheless, current mainstream physics does prefer time to be kept in a box – and this is where Smolin breaks out. He shows us that pretty well all of physics is based on the idea that we are dealing with closed systems, where in reality there is no so such thing – meaning that it is quite possible that pretty well all existing physics is just an approximation. And he comes up with a mechanism where time, something that actually ticks by and has a universal meaning, can exist (though at the expense of space being quite so real as we thought).

In doing this, Smolin will have irritated a whole lot of physicists. Some will simply not agree – any string theorists, for example, would dismiss his loop quantum gravity viewpoint. Many others will simply not be able to cope. Physicists are, on the whole, a fairly conservative bunch (with a small ‘c’) – they aren’t very good at coming with radical shifts in viewpoint like this. Of course this doesn’t make Smolin right, but it is a fascinating bit of speculation.

The book isn’t perfect. Smolin’s writing style is workmanlike, but suffers from too academic a viewpoint – he doesn’t have the common touch. Oddly, it’s not so much that he baffles us with science, but rather he baffles us with labels which don’t have enough science attached. He has a tendency to use terminology and then say effectively ‘but you don’t need to know what that’s all about.’ I think popular science is much better if you avoid the jargon and instead explain what lies beneath. Also he uses really scrappy hand-drawn illustrations that I suspect are supposed to make them look more friendly and approachable, but actually makes them practically incomprehensible.

These are minor moans though. Whether or not you agree with the physics, this is a book to get you thinking, awash with ideas and totally fascinating. It isn’t the easiest popular science book to understand – it is very much of the ‘read each sentence slowly, and some times several times’ school, yet it is a superb contribution to the field that really puts that cat among the pigeons. Three cheers for Lee Smolin who is, for me, apart from lacking that common touch, the nearest thing we have in the present day to the late, great Fred Hoyle.

Hardback:  

Kindle:  

Review by Brian Clegg

Dice World – Brian Clegg *****

Featured

Posted on by
1

As human beings we are adept at seeing patterns. It’s how we understand the
world. But as Dice World makes plain, reality is all too often driven by
DiceWorldrandomness, without a pattern in sight. At an entertaining canter, Brian Clegg takes us through the way superstition turns correlation into causality; why economists are so bad at predicting real human responses; and how the power of statistics can reveal hidden truths that, if it weren’t for the logical walkthroughs, you just wouldn’t believe. The book starts by showing us how the world seemed an ordered place - briefly in-line with Newton’s clockwork universe – and then how the cracks began to show when it proved impossible to accurately predict the movement of just three bodies in space.

Chaos and randomness intertwine – chaos technically predictable but practically impossible to do so, while true randomness, the behaviour at the heart of quantum theory is totally unpredictable but often fits neat distributions. You’ll meet the smartest person in the world – and strange creatures like Schrödinger’s cat and
Maxwell’s demon; see why a window at night is a fiendishly complex quantum
device with randomness and probability at its heart; and find out what’s
going on with entropy, the end of the universe and free will. Oh and
discover how to get the best prediction of whether or not someone owns a
golden retriever.

In equal parts fascinating and mind-boggling this is a real revelation if
you have any interest in why things happen (and why they go wrong). We’re no
good at probability and we hate randomness. We rarely see either of them at
work – and yet they’re everywhere. Clegg has a gift for making this kind of
thing approachable and informative but still fun. With this book to hand
you’ve got your best chance of understanding just what’s going on in the
universe; and to have some laughs along the way. Not to mention discover how
to win a sports car rather than a goat. Which can’t be bad.

Large Paperback:  

Kindle:  

Review by Peet Morris

Please note, this title is written by the editor of the Popular Science website. Our review is still an honest opinion – and we could hardly omit the book – but do want to make the connection clear.

Unraveling the Universe’s Mysteries – Louis A. Del Monte **

Posted on by
2

As I have mentioned before, we are distinctly fussy about taking on self-published books, but made an exception in this case. ‘Unraveling’ combines an exploration of the currently accepted cosmology with some speculative alternative physics ideas and even a quick delmontediscussion of the existence of God.

Although I was prepared to set aside an aversion to self-publication, it does show through quite strongly in this book, and I ought in all fairness to mention the bad side of this first. Like almost all self-published books, the print layout on the page looks wrong – more like a Word document than a book. This isn’t insuperable, but mildly irritating. What’s worse is that it is very clear that the book hasn’t been professionally edited (or if it has, the author should get his money back). There are far too many errors. So, for instance, when talking about string theory, at one point it is sting theory, and at another spring theory. Professor Ronald Mallett, who is discussed at some length, quite often only had one ‘t’ in his name. And so it goes on.

Putting that aside, what we get here is a combination of a quite reasonable introduction to the big bang and string/M theory with some personal speculation from Mr Del Monte and an interesting exploration of some ‘mysteries that still baffle modern science.’ I ought to divide this into three: how well Del Monte does at explaining the basic science, how readable the book is, and what to think of Del Monte’s original theories.

Most of the basic science is good and some is reasonably well explained. The author is a lot better on cosmology than he is on quantum theory and relativity, which can be rather confusing in the way they are covered, but overall it’s a workmanlike job. What is slightly worrying is that the author doesn’t seem to understand special relativity, as he suggests that the ‘twins paradox’ is presented as only being an illusion, because the effect is symmetrical. This runs counter to even undergraduate level physics – in any special relativity textbook it is clearly explained why the twins paradox is real and not an illusion because the symmetry is broken – one twin is accelerated and the other isn’t. That’s worrying.

As for the readability, the book starts off pretty well in an approachable, quite chatty fashion, but it suffers from not having any clear structure, jumping episodically from chapter to chapter, and there is no evidence that the author has any great expertise in science communication. There’s nothing particularly new in the basic science here, and there are plenty of other books on cosmology and string/M-theory that do the job of getting them across better.

We are left with the author’s own theories. I have a problem here. I have no issue with a working scientist with academic standing presenting their own, speculative theories. However when someone without appropriate credentials does so, it is worrying. Del Monte has a masters in physics and then spent his working life as an engineer. Nothing wrong with this, but it does not make him a ‘physicist’ as he is described, and it does not give a great deal of weight to his theories. To be fair I am not saying that they are in the typical ‘Einstein was wrong, my new theory shows why’ fruit-loopery class. There is some interesting reasoning here – but I am not qualified to say if there is anything of interest, and neither, really is Del Monte.

Taking all this into account, this isn’t a bad book, but the combination of self published, poorly edited, not brilliantly written, and combining nothing that isn’t done better elsewhere on standard cosmology with some pet personal theories does not make it one I can recommend either.

Paperback:  

Kindle:  

Review by Brian Clegg

Neils Bohr and the Quantum Atom – Helge Kragh ***

Posted on by
Reply

This is a bit of specialist one. If you don’t have a physics degree, don’t bother to read any further. Neils Bohr and the Quantum Atom is not intended to be popular science (if you want a more approachable book, try Abraham Pais’s Niels Bohr’s Times), quantbohrbut I was very interested to read it as it’s a subject that is close to my heart.

Bohr himself tends to be underrated – he tended to come across rather badly when public speaking, and some of his quasi-philosophical pronouncements on the nature of quantum physics were painfully obscure. But we must not forget the huge contribution he made to kick-starting quantum theory, starting with his key development of the quantum model of the atom.

Although the book does plunge into equations on a number of occasions it is primarily a historical narrative of the development of Bohr’s model of the atom, including a fair amount of biography, from his early thoughts at Manchester in 1912 to its full fruition and subsequent transformation by the new quantum mechanics in the 1920s. I would be lying if I said that reading it wasn’t quite hard work – but if you really want to get a feel for the detailed process of the development of one of the key foundations of twentieth century physics, the book is unparalleled. There is a lot of detail – but this is about real science, not the sanitised version.

Overall, if you are the right reader (and I was), very satisfying.

Hardback:  

Kindle:  

Review by Brian Clegg

Neils Bohr’s Times – Abraham Pais ****

Posted on by
1

Fully, if clumsily titled Neils Bohr’s Times, in physics, philosophy, and polity, this is the definitive scientific biography of Bohr by fellow physicist Abraham Pais who knew and worked with him.

paisbohrThe good news is that this chunky title will give you an in-depth look at Bohr and his work. From his early days in Copenhagen, through his brief but fruitful stay in the UK, his return to Denmark, the rush to safety in the Second World War and his gradual move to elder statesman of quantum physics, it’s all here.

As is often the case with a biography written by another scientist, the science content is quite heavy and sometimes not the easiest to digest, but it is worth battling through, and the picture of Bohr himself that comes out of this book is second-to-none. Niels Bohr sometimes gets a rough time of it, in part because his own communication was often rather opaque, but Pais will really open your eyes to Bohr’s importance.

The book dates back to 1991 but is none the worse for that. If you really want to understand the development of quantum physics in its historical and scientific context, this should be on your reading list.

Hardback:  

Paperback:  

Review by Brian Clegg

The Quantum Divide – Christopher C. Gerry & Kimberley M. Bruno ***

Posted on by
1

Broadly speaking, science books are either popular science or textbooks. The popular science book is aimed at a general audience with little or no science background required and fills in the basics in a far more interesting way than science was every taught at school. The textbook does the business of educating with the theories, while not worrying too much about the historical context, with readability always coming a distant second. It assumes the reader has science and maths education to the required level. But The Quantum Divide, perhaps in keeping with the concept of quantum superposition, manages to be a bit of both at the same time.

What we have here is an exploration of quantum physics and the divide between the world of quantum particles and the macro universe. It is pitched in a way that I have simply never seen before. For a very narrow band of readers this book is absolutely superb. If you have been fascinated by a book on a quantum subject, like my own The God Effect on quantum entanglement, but want to dig into more depth about what is actually going on, and what was really undertaken in some of the experiments you usually have to either read a textbook or go to an academic paper. But both of these are pretty impenetrable and too maths-heavy for the general reader. Gerry and Bruno give that extra meat without requiring heavy duty mathematical support. There are equations in here, but they are used as shorthand, not to do maths. The result is quite extraordinary – it really expands on anything you can get from a popular science book without being too heavy to cope with, and for that, the authors need a huge pat on the back.

To be honest, though, I don’t think most popular science readers actually want this extra detail. On the other hand, university level physics students will find it too basic and not mathematical enough (though it could provide a good introduction before a course). This is a great book for, say, science journalists and those with a similar level of semi-professional interest – but probably not for many others.

The other slight problem is that the authors can occasionally be quite prissy and negative about guess who… science writers. Their audience in all probability. Take this quote:

Quantum theory does not predict that an object can be in two or more places at once. The false notion to the contrary often appears in the popular press, but is due to a naïve interpretation of quantum mechanics.

The problem with this attitude is that it entirely misses the point. All descriptive models of something as counter-intuitive as quantum theory are inevitably approximations – what they are really doing here is not liking someone else’s language, even though it gets the basic point across better than their version. I don’t think this is any more a problem than when physicists speak of the big bang or dark matter as if it they are facts, rather than our current best accepted theories.

There’s a similar cringe-worthy section where the authors attack the suggestion that light is a particle in the true sense, which again seems nit-picking. Their argument seems to make little sense and given Richard Feynman was happy to say ‘I want to emphasize that light does come in this form – particles’ I find their position hard to justify. So there are a couple of places where a particular slant of interpretation gets in the way of what otherwise is excellent explanation – but I think that can be forgiven.

Overall, then, a worthy and fascinating book but one that I suspect will only ever have a very limited audience.

Hardback:  

Review by Brian Clegg

The Particle at the End of the Universe – Sean Carroll ****

Posted on by
1

The possible discovery of the Higgs boson has prompted a flurry of books – in part because it’s significant (and because the Large Hadron Collider is a sexy bit of kit) and in part because the whole business of the Higgs field and its importance for the mass of particles is one of the most obscure and unlikely bits of physics in the current canon.

I have really mixed feelings about this entry in the genre from physicist Sean Carroll. It’s not because his book is too difficult to understand – it’s almost because it’s too easy. Generally speaking, there are three levels of good popular science. There’s TV news popular science, which cuts a lot of corners to make things totally simplistic, but manages to get the message across quickly. There’s the kind of book a good popular science writer will produce – highly approachable and readable, giving a lot more depth than the TV news and the best way to actually get an understanding of what’s going on for most of us, but still cutting some scientific corners. And there’s the kind of book a good scientist will write, which will probably go over your head the first time you read it, but if you persevere will give you the best illusion of knowing what the real science is about and getting some feel for the world of the scientist.

In his previous book From Eternity to Here, like Cox & Forshaw’s Why Does E=mc2, Carroll didn’t pull the punches. Much of the text was readable, but it may well have taken several attempts to get it to sink in. It was the perfect popular science book by an academic. Parts of this one, unfortunately verge on TV science. Some of it is so fluffy and approachable that it almost disappears into meaninglessness.

Luckily, this isn’t true of all the book. The early parts are worse. Oddly, he gets significantly better when talking about the building of the Large Hadron Collider than he does in his first attempts on the physics. And it is worth persevering as Carroll improves with his approach further in (best of all are a few appendices where he goes into more detail and we see the old, mind-bending Carroll emerging).

Some specific issues I had: it was really irritating that Carroll uses units like degrees Fahrenheit and miles rather than scientific (or European) units throughout. This is real poor TV science stuff. A lot of his science is what I’d call ‘plonking’ he states it as if it is absolute truth, not the current best theory. So, for instance, he speaks of dark matter as if it were certain fact (nary a mention of the rival MOND theory). And he says at one point ‘The world is really made out of fields. Sometimes the stuff of the universe looks like particles… but deep down it’s really fields.’

I have two problems with this. One is that one of my absolute heroes was Richard Feynman and he said of light ‘I want to emphasize that light does come in this form – particles.’ If particles are good enough for Feynman, they’re good enough for me. Secondly I think that what Carroll should be saying is ‘fields are the model that work best to describe what’s out there.’ In the end it’s a human devised model of something we can only inspect extremely indirectly. It is almost bound to be wrong – it’s just better than anything else we have at doing the job. (Yet.)

Perhaps the worst problem is the way he oversimplifies. Oddly this is a classic problem when a scientist is writing popular science (and why a good science writer is usually better) because he doesn’t know what the lay reader finds puzzling, so doesn’t bother to explain. His explanation of the application of symmetry to physics simply doesn’t fill in enough of the gaps. He says, for instance, that a mentos and diet coke experiment is symmetrical in all sorts of ways – you can point it in any direction, or translate it to any position and it works the same. Clearly this isn’t true. It wouldn’t work the same if the bottle was upside down, pointing straight at the ground, nor would it be the same if you translated it under the sea or into space. It’s a classic case of handwaving generalisation, missing out all the provisos and so making the explanation fail.

It’s certainly not a bad book – but I did prefer its rivals on a couple of counts. For a better heavy duty attempt at the physics, Frank Close’s The Infinity Puzzle wins (though that definitely is a ‘several reads to get it’ book). And for the best overall description of the search for the Higgs, combined with the most approachable but informative information on the Higgs field and the whole standard model of particle physics I’d recommend Higgs by Jim Baggott. But Sean Carroll’s book still did have a lot going for it and is still well worth considering.

Hardback:  

Kindle:  

Paperback (from May 2013):  

Review by Brian Clegg

Quantum Physics for Poets – Leon Lederman & Christopher Hill ***

Posted on by
Reply

I am always suspicious when a book makes a big thing about the author being a doctor. When you see ‘The Wonder of Vitamins’ by Fred Doser M.D., you just know it’s more about selling product than information. Although not quite as bad, I was a little put off by the way the cover of this book tells us it’s not by Leon Lederman, but Leon LedermanNobel Laureate. Now don’t get me wrong, Leon Lederman, the scientist who came up with the nickname ‘God particle’ for the Higgs Boson is a real scientist, and is, indeed, a Nobel Prize winner. But I couldn’t help but find this splashing around of the fact a distraction rather than an aid. Was his Nobel Prize for explaining physics to ordinary folk? No. Does it make him any better at it? No. So why such a big thing of it?

Once you’ve got past this branding, it’s certainly an interesting title. Unlike The Cosmic Verses, this isn’t a book that’s all in rhyme, though admittedly a few poems do appear. It’s more a book that is intended to be read by people who don’t read science books like, well, poets.

It certainly manages to fulfil half the title. There’s plenty of quantum physics in here, along with a bit of Newton/Galileo style science to give the background. And Lederman & Hill don’t hold back in going into some quite hard to follow areas. They spend quite a while, for instance, on Bell’s theorem, the indirect way by which it’s proved that quantum entanglement really does involve non local effects, rather than carrying information in hidden variables. But the trouble is, I don’t get the impression that either of the authors are great communicators. Lederman’s God Particle book is significantly more readable, but I think his co-author was a writer. The fact is any poet (or anyone else not reasonably versed in science) is going to struggle to keep up with this book and having a few cartoons (which quickly die out) doesn’t transform it into effective science communication.

What you end up with, then, is not a book for poets, but rather one that gives an introduction to quantum theory for, perhaps, those who are nearing the end of school and are hoping to study physics at university. The trouble is, even that market is better covered Brian Cox & Jeff Forshaw’s The Quantum Universe. If Leon Lederman had brought hosts of personal insights to the table, it would have made this book worthwhile, but there are only a couple of very short instances. It’s fine as alternative to Cox and Forshaw, but certainly isn’t for those of a poetic disposition.

Hardback:  

Also on Kindle:  

Review by Peter Spitz

The Quantum Universe: everything that can happen does happen – Brian Cox & Jeff Forshaw ****

Posted on by
1

Brian Cox has picked up a lot of fans (and a few parodies) for his light and fluffy ‘here’s me standing on top of a mountain looking at the stars’ TV science shows – no doubt a fair number of them will rush out and buy his latest collaboration with Jeff Forshaw. They will be disappointed. So, I suspect, will a number of My Little Pony fans, as with its rainbow cover and glittery lettering it only needs a pink pony tail bookmark to complete the look.

The reason The Quantum Universe will disappoint is not because it is a bad book. It’s brilliant. But it is to Cox’s TV show what the Texas Chainsaw Massacre is to Toy Story. It’s a different beast altogether.

As they did with their E=mc2 book, but even more so here, Cox and Forshaw take no prisoners and are prepared to delve deep into really hard-to-grasp aspects of quantum physics. This is the kind of gritty popular science writing that makes A Brief History of Time look like easy-peasy bedtime reading – so it really isn’t going to be for everyone, but for those who can keep going through a lot of hard mental work the rewards are great too.

More than anything, I wish this book had been available when I started my undergraduate course in physics. It would have been a superb primer to get the mind into the right way of thinking to deal with quantum physics. Using Feynman’s least action/sum over paths with ‘clocks’ representing phase, the authors take us into the basics of quantum physics, effectively deriving Heisenberg’s uncertainty principle from basic logic – wonderful.

They go on to describe electron orbitals, the mechanics of electronic devices, quantum electrodynamics, virtual particles in a vacuum and more with the same mix of heavy technical arguments, a little maths (though nowhere near as much as a physics textbook) and a lot of Feynman-style diagrams and logic.

The reason I think I would have benefited so much is that this book explains much more than an (certainly my) undergraduate course does. Not explaining why quantum physics does what it does – no one can do that. But explaining the powerful logic behind the science, laying the groundwork for the undergraduate to then be able to do the fancy maths and fling Hamiltonians around and such. It is very powerful in this respect and I would urge anyone about to start a physics degree (or in the early stages of one) to read it. I would also recommend it for someone who is just really interested in physics and is prepared to put a lot of work into reading it, probably revisiting some pages several times to get what Cox and Forshaw have in mind – because they don’t ease up very often.

What I can’t do, though, is recommend this as general popular science. It isn’t the kind of excellent introduction that gives you an understanding of what’s going on in quantum theory, a view of the mysteries and a broad understanding of what the topic is about. This book is just too hard core. I’d suggest that 90% plus of popular science readers shouldn’t touch it with the proverbial barge pole. If that sounds condescending, it isn’t meant to be. Good popular science can and does have a lot more content and thought provoking meat than a typical Brian Cox TV show – but this book goes so much further still than that, inevitably limiting its audience.

Hardback:  

Also paperback from June 2012: 

Also on Kindle:  

Also on Audio CD:  

Review by Brian Clegg