Lee Smolin: Time Reborn (2013)

Edition: Allen Lane, 2013
Review number: 1494

 Annoyingly poorly argued book about moving beyond current ideas of time in physics, with some interesting ideas. Smolin spends most of the book discussing the "timelessness" of modern physics, both relativity and quantum mechanics, without ever properly defining what he means by the term. It's clearly not whether the theories have a time parameter in them, but it seems in some places to mean that time is treated as a whole, as it is in the "block universe" of relativity, and in others that the laws of physics themselves do not change. Smolin thinks we need to look at changing laws in order to fix some of the problems with these theories, but his ensuing discussion of what form these changes may take is infuriatingly inconsistent and contains logical flaws (there is a particularly glaring one on p.163 of this edition). Sometimes he seems to be envisaging laws changing only at the creation of a new universe (if his earlier ideas about black holes in one universe containing new generations of universes inside them is adopted); at others, he seems to be talking about changes between distant parts of the same universe or over time, again in a single universe. Where was the editor when they were needed?

My rating: 4/10.

Mark Alpert: Final Theory (2008)

The quoted reviews of this novel almost all compare it to The Da Vinci Code, and that is probably as good a place as any for me to start mine. Alpert is clearly a far better writer than Dan Brown, which may seem like faint praise, but the idea behind Final Theory is so closely related to The Da Vinci Code that it needs to be said.

Alpert studied physics, and now works for Scientific American, and the secret which is at the heart of Final Theory is a physical theory rather than a religious idea. Towards the end of his life, Einstein spent a lot of time searching for a unified theory which would bring together the physical forces and provide an explanation for the results of quantum theory, something which he was uneasy with despite his involvement in its early stages. He never succeeded in doing this. Alpert has combined this idea with Einstein's belief in pacifism, and the secret in Final Theory is a unified theory which Einstein did find, only to conceal it because of his concerns at the military uses to which it could be put. However, Einstein ensured that the secret theory would survive, by telling parts of it to each of his three assistants, so that if the world became peaceable, the theory could be reconstructed and revealed.

Many years later, one of the assistants posts his portion of the theory online before killing himself, and then Einstein's worst fears begin to be realised as several groups including the American government start a hunt for the keepers of the rest of the secret. The central character of Final Theory, David Swift, is, like Alpert himself, a science journalist who was once a physics graduate student. He is summoned to the hospital bed of his former professor, who was one of the three assistants, to be told a series of apparently meaningless numbers, which is designated "the key" by the dying man. This was the secret for which he had been attacked in his apartment and which leads the FBI taskforce which to take over the investigation from the NYPD, and then to illegally detain David. When the detention centre David is taken to is attacked by a Russian mercenary, David goes on the run, trying to find the secret - not necessarily the best thing to do in the circumstances, I suspect, but this gives a direction to his flight.

The big problem with Final Theory, as have been gathered from this summary, is that even for a thriller the plot is extremely implausible. It hinges around the willingness of large numbers of government employees to act illegally on a minimal suspicion that David might know something about the secret, and that the secret will be something which can be used to create a devastating weapon (and if it were possible, the development process involved would be decades long);  but this is bread and butter to a conspiracy theory novelist. The problems arise more from David's escape and the ensuing chase across the United States, during which he and other amateurs consistently outwit or have superior skills to those of trained police and mercenary soldiers. Thrillers do not have to be plausible in these respects, but the action sequences in Final Theory do not distract the reader enough to stop holes in the plot being noticeable.

Unsurprisingly given Alpert's background, the physics used as the background is interesting and works well. His idea about how Einstein could plausibly have found a unified theory despite his rejection of quantum mechanical uncertainty is quite convincing, though  those readers who have never read popular explanations of relativity and quantum mechanics might find unexplained terms including "timelike closed curve" intimidating - and these people probably make up most of the intended readership for Final Theory. The periodic pauses in the action during which the physics is discussed is probably the reason why the holes in the plot are quite as evident as they are.

Entertaining for the most part, but generally unconvincing and unlikely to hold up for thriller fans not already interested in the science. My rating - 3/10.


Edition: Pocket Books, 2009
Review number: 1438

Janna Levin: How the Universe Got Its Spots: Diary of a Finite Time in a Finite Space (2002)

Edition: Weidenfeld & Nicolson, 2002
Review number: 1123

It is not, generally speaking, usual for modern science books to be concerned with the private lives of their authors, even though it is inevitable that the scientific work that they have done will have been influenced by this. This is a result of the idea that scientific ideas should be valid without any cultural context, but the anecdotes which litter popular science books demonstrate how important some subjectivity is for interesting the reader - few people read textbooks for pleasure. An excellent example is Pais' 'Subtle is the Lord...', which is a biography of Einstein which places equal emphasis on his life story and an explanation of his ideas.

How the Universe Got Its Spots is based on a series of letters written by cosmologist Janna Levin to her mother, which seek to explain her work. I don't know how much Levin's mother already knew, but the letters don't presuppose significant amounts of scientific and mathematical education; which makes even writing the letters in the first place quite a brave thing to do; a parent is a far more difficult audience than some unknown reader. The letters also contain details of her personal life over a two year period, a diary of the gradual breakdown of Levin's relationship with musician Warren.

Levin's work is in the topology of cosmology, trying to come up with possible descriptions of the large scale shape and structure of the universe. This may be discernible as patterns in such measurements as the COBE map of variations in the cosmic background radiation. The ideas which are introduced to explain this include a fair amount of topology, which is one of the more entertaining branches of mathematics. The explanations of the ideas behind Levin's work are clear and simple (though as someone who has studied topology I might well not be a good judge).

It is for the combination of the science and the personal history that readers will pick up How the Universe Got Its Spots, however. The way that the two are put together makes the book reminiscent of a novel which was a bestseller a few years ago, Sophie's World by Jostein Gaardner. That book, though intended to introduce children to philosophy, was enjoyed by large numbers of adults; and if you liked it, you are pretty certain to like this.

Nigel Henbest and Michael Marten: The New Astronomy (1983)

Edition: Cambridge University Press, 1983 (Buy from Amazon)
Review number: 1067

After almost twenty years, the contents of this book cannot really be described as "new" astronomy any more. It is a lavishly illustrated description of the then current achievements and methods in observational astronomy, with an emphasis on the discoveries made by extending this field beyond the visible part of the electromagnetic spectrum. Developments since 1983 include massive expansion in satellite observations with the deployment of the Hubble Space Telescope, detection of extra-solar planets, work to find incontrovertible evidence of black holes, more sophisticated computer analysis of data, and so on. Most of these are building on the methods described in The New Astronomy rather than being revolutionary and new in themselves.

The illustrations are of primary importance in The New Astronomy; the text is designed to explain the pictures rather than the other way round. It is appropriate that Cambridge have taken the unusual step of giving Michael Marten, the picture editor, a co-author credit. The two aspects of the book are well integrated, but it is the sumptuous illustration which makes the book stand out. I'm going to look out for a more recent equivalent (or, indeed, a revised edition) - it's a book which should be in the library of anyone interested in modern astronomy.

John D. Barrow: The Universe That Discovered Itself (1987, 2000)

Edition: Oxford, 2000 (revision of The World Within the World, 1987)
Review number: 1001

Barrow's book, an updated version of The World Within the World, is a philosophical look at the history of science and contemporary scientific ideas with a rather unusual slant. It takes a list of nine statements about the laws of science and how they relate to the underlying reality of the universe, and then sees a general trend up to the work of Newton to establish these statements, followed in the twentieth century by the opposite trend with the development of new theoretical frameworks very different from the Newtonian one. These statements are things like "Space and time exist" or "The world can be described by mathematics", and are a set of basic philosophical assumptions about the universe, informing scientists' attitudes to physical theories.

The Universe That Discovered Itself is aimed at the experienced reader of popular science. Even though brief explanations are given, it would be difficult to follow without a previous acquaintance with relativity, quantum mechanics, string theory, and the anthropic principle among other ideas. With a familiarity with these concepts and an interest in the philosophical, there is much pleasure to be obtained from the book. The title refers to the thought that we, as part of the universe, have discovered a great deal about it, and is particularly appropriate given the quite lengthy discussion of the role of the observer in quantum mechanics and particularly quantum cosmology.

The presentation is typical of Barrow, with each section enlivened by interesting and frequently amusing quotations, including the following anecdote. In an Oxford physics viva in the 1890s, a student was asked to define electricity. His response was that he did know but had forgotten, to which the examiner drily replied, "How very unfortunate. Only two persons have ever known what electricity is, the Author of Nature and yourself. Now one of them has forgotten".

I'm not sure how radical a revision was made to the earlier book, and there are some sections which seem to be less up to date than others, which is a pity. Still, I found The Universe That Discovered Itself a fascinating exploration of the philosophy behind modern physics.

Bernard Lovell: In the Centre of Immensities (1979)

Edition: Hutchinson, 1979 (Buy from Amazon)
Review number: 961

Now sadly out of date, Bernard Lovell's wonderful popular science book was an inspiration to me in my teens. It tells a familiar story, the history of human understanding of the cosmos and our species' place in it, but stands out because of the excellence of Lovell's writing and a slightly unusual viewpoint.

Most popular science books seek to make the reader wonder at the marvels of the universe, particularly the paradox that the best descriptions currently available are not intuitively obvious. There is a subtext to this, though, which is that science is wonderful for having discovered so much out about the universe and for describing things in such a subtle way.

Lovell is interested in the wonders of the universe, but he is also concerned with the way in which changing perceptions of the universe have affected our species' view of itself. A considerable proportion of the book, including the whole last chapter, is about morality, something which it has become fashionable for scientists to ignore completely with the argument that scientific research is morally neutral. The problem with this is that the application of research is not neutral, and there is certainly some scientific work which is so tightly tied to a particular application that it can itself hardly be termed neutral (biological weapons work, for example).

The foregoing perhaps overstates the importance of this aspect of In the Centre of Immensities. It is this, though, which makes it different from most histories of cosmological speculation, and it is this which made it such an important book to me.

Stephen Hawking: A Brief History of Time (1988)

Edition: Bantam, 1998 (revised tenth anniversary edition)
Review number: 892

It is difficult, from the contents of A Brief History of Time, to see how it managed, famously, to become the least read bestseller of the twentieth century. The answer, of course, is the romance of Hawking's life and the way in which he was able to overcome his disability.

The book itself, in this revised edition marking the tenth anniversary of the original publication, is a clear account of modern cosmology from one of the subject's leading researchers. To anyone who has read this sort of thing before, it contains no particularly difficult concepts, and its style is simple and generally easy to follow (with occasional lapses into more technical language). Hawking's involvement in many of the advances in the field lends his writing a particular authority, and even those who read a lot of popular science will find this classic a useful summary, more or less up to date. (The current research into neutrino violations of the Standard Model is the main development to have taken place since publication.)

John Barrow: The Origin of the Universe (1994)

Edition: Phoenix, 1995
Review number: 649

Part of a series of explanations of important areas of current science by leading science writers, The Origin of the Universe would be an ideal place for to start for a reader with virtually no scientific background who wants to try to understand something of current thought on the subject. It is concise and simple, admirably written, and has the odd point of interest even to a voracious reader of popular science books. It reminded me of the science books of Isaac Asimov, and is a worthy successor to his books on cosmology, written skilfully in the same spirit yet up to date. I found Asimov's books fascinating when I was a teenager - they were all about the interesting science they didn't teach at school - and I think that The Origin of the Universe could have the same effect on an interested teenager today.

Kip S. Thorne: Black Holes and Time Warps: Einstein's Outrageous Legacy (1994)

Edition: Picador, 1994
Review number: 590

Picador has the makings of a most interesting series of popular science books. The idea is to get a personal picture on topics of current interest, written by prominent characters involved in the research. However, as a series, it rather shoots itself in the foot by omitting any listing of the other books; this one merely mentions that there are four earlier volumes, information of absolutely no help in identifying them.

There are problems in this book too, particularly the dull first half. I would imagine that, given their importance in twentieth century physics, quantum mechanics and relativity will be explained in every book in this series, and the length at which these explanations are repeated is really unnecessary. I feel that more writers should follow Brian Greene's example in The Elegant Universe, and keep the explanation as brief and to the point as possible, pointing the reader who has never read a detailed account to other books. (There can be few public libraries which would not have at least one good book on this subject.) Certainly, Black Holes and Time Warps could do with a good deal of editing, if not re-writing, in its chapters on these subjects.

There is a sudden improvement as soon as the account turns to the renewed research into black holes following the end of the Second World War, particularly once Thorne himself becomes involved during the sixties. He is clearly quite a character, involved in smuggling manuscripts out of the Soviet Union to be published in the West, and in several bets made about then current questions about the detailed nature of black holes. He is also effectively responsible for the discovery of the possibility that if a stable wormhole could be created and manipulated in a specific manner without destroying it, then it would form a type of time machine. (The mass media coverage of this result included a photograph of Thorne "doing physics in the nude".) As can be expected, his account of black hole research includes much that is about the personalities of those involved; illustrations include private snap shots of dinner parties.

The second half is interesting, well explained popular science; any reader put off by the first four chapters is missing out.

Brian Greene: The Elegant Universe (1999)

Edition: Jonathan Cape, 1999
Review number: 552

The Elegant Universe is not, as the title might suggest, an examination of the philosophical question of why so much of the operation of the physical universe can be described by relatively simple mathematics. Instead, it is a popular account of superstring theory, currently considered to be a major candidate for a cosmological "theory of everything". Strangely enough, from a mathematical point of view, the picture painted is far from elegant, string theory still being full of supposition, reasoning by analogy and with known problems. The elegance is in the approach; if it did provide, at the end of the day, a unified picture of quantum mechanics and general relativity, it could then be considered elegant in other senses.

The book starts, as many popular science books do, with a description of the origins and theory of general relativity, yet even here it scores over many similar volumes by finding descriptions and illustrations I at least had not seen before, and new details of well known pedagogic analogies such as the rubber sheet model of relativistic curved space.

The focus of the book is the string theory, and an admirable job is made of the task of conveying something of what this incredibly difficult mathematical discipline is about and why it is important, without using any mathematics - no equations at all. (It would probably be rather heavy going to someone who has not at least a reasonable familiarity with popular accounts of quantum mechanics, however.)

Greene is an enthusiast for string theory, and an optimist regarding both the completion of the theory and the description of the universe by the theory. These attributes stem, as does the authoritative nature of the narrative, from his position as an active researcher in the field. Some space is given to the arguments of sceptics, but not much. String theory is certainly a worthwhile area of research in mathematical physics, and probably the current best bet for a theory of everything. Objections mainly stem from the feeling that because of this work in the field tends to be overhyped, or amount to philosophical objections to the idea of an ultimate theory. In the first category falls the frequently made point that superstring research has produced little (if anything) in the way of experimentally verifiable prediction (Greene counters this by pointing to parts of the theory which he feels are close to doing so), or that much of the mathematics is fragmentary (since it is so difficult; only more work can fill in the gaps). The second category is barely touched on, though forming a major part of the discussion in such books as John Horgan's The End of Science or John Barrow's Impossibility. Philosophical speculation is by its very nature difficult to answer, and is was perhaps wise not to stray into this territory.

The Elegant Universe is a fascinating book, a clear account of one of the most complex parts of modern science. It is worth reading by anyone with an interest in the physical investigation of the fundamentals of the universe.

John D. Barrow: Impossibility: The Limits of Science and the Science of Limits (1998)

Edition: Oxford University Press, 1998
Review number: 483

In what is almost a response to John Horgan's The End of Science, Barrow examines the limitations of scientific thought from several different points of view with the aim of working out what science can say about what it cannot say. He skims quickly over some of the problems Horgan talks about, such as the increasing economic cost of scientific experimentation; these limitations are not scientific in nature (non-scientific events such as a change of government may change their nature) and there is little that can be said about them beyond acknowledging their existence.

Barrow is far more interested in the limitations inherent in modern scientific theories, such as the impossibility of knowing what happens outside the edge of the visible universe. He concentrates on the less well known ideas, rather than ploughing once again the well worn furrow of the popular account of relativity and quantum mechanics. His final section is a brief but sensible account of Gödel's Incompleteness Theorem and its relationship to physics. The problem with this relationship is that it is only possible to determine its nature when the more basic question of how mathematics is embodied in the universe is answered. If mathematical physics is only a description of patterns in the universe, for example, then there is not necessarily any connection. Even if sufficiently complex mathematics is in some way embodied in the universe - you need to have arithmetic with both addition and multiplication - then it is not at all clear what the physical version of a Gödel Undecideable Sentence would be (it would depend on the precise nature of the embodiment, for a start).

Barrow is less polemic than Horgan, more interested in the nature of the various types of scientific impossibility than in ramming home the point that there are limitations to science. Barrow is much more pro-science than Horgan - he is after all a research physicist - which means that his book is less excitingly iconoclastic but perhaps more informative. (The structure of the book also helps here; Horgan's is organised around interviews with prominent scientists which means that his main philosophical points are hidden behind personalities.)

Paul Davies: About Time: Einstein's Unfinished Revolution (1995)

Edition: Viking, 1996
Review number: 424

About Time is an eminently readable popular account of the current ideas about time in physics, with a short historical section examining philosophical perceptions of time from the ancient Greeks to the time of Newton. The main concerns of the book are to explain the role played by time in the keystones of modern physics, general relativity and quantum mechanics. Since much of physics is concerned with processes, time can be used as a single theme to motivate a discussion of many of the more interesting aspects of modern physics.

The nature of time and its role in the cosmos also lie at the heart of some of the unsolved problems of physics, many people thinking that these issues will provide the key to the next generation of physical theories. Most prominent among these is the asymmetry of time, a major problem when underlying theories would be unchanged if time ran backward rather than forward. In slightly different areas, issues of human perception of time are briefly touched upon as well as what exactly we might be measuring with different kinds of clocks.

The descriptions of relativistic and quantum effects are now the commonplace of popular physics, and the most interesting parts were those dealing with more unusual matters, such as the nature of the interior of black holes or the asymmetry in kaon decay. The device of having a second voice used as a sceptic to facilitate the discussion is slightly annoying but not a big problem.

John Huizenga: Cold Fusion (1992)

Edition:  Oxford University Press, 1993
Review number: 287

It is now almost exactly ten years since the press conference was held which launched cold fusion before the world, and it seems now an almost forgotten chapter in the history of science in the twentieth century. At the time, however, the amazing promise offered by cold fusion should the supporters' claims prove true, and the generally unsubstantiated and (to many experts) ludicrous nature of the claims led to angry and passionate exchanges. Huizenga, as chair of the committee appointed by the US Department of Energy to investigate the claims of cold fusion, is well placed to offer an account of the whole affair (though his sceptical  attitude - to my mind the proper one - led to accusations of bias and prejudice).

To quickly summarise the history of cold fusion, in 1989 two chemists from the University of Utah held a press conference to announce the discovery of the century: when electrolysing heavy water, they seemed to be getting out more energy than they were putting in. They ascribed this to fusion of the deuterium which takes the place of normal hydrogen in heavy water. Scientists have been working on deuterium fusion for years, but the possibility that it could happen at room temperature seemed so remote that their work had been concentrated on super-heated deuterium plasmas, kept under pressure by extremely intense magnetic fields (hence the name cold fusion for the new discovery).

Critics picked up several things which acted as danger signals almost instantly. The speciality of Pons and Fleishmann was electrochemistry, massively removed from nuclear physics. They had carried out their experiments and come to their conclusions in a way that didn't satisfy the nuclear physics community that the conclusions were correct. The way that fusion works is that it produces larger atoms than the ones started with along with the energy, and the two of them had not systematically looked for evidence that these atoms had been produced with good quality detectors. By the standard mechanisms of nuclear fusion, to produce the amount of excess heat they claimed to have done, Pons and Fleishmann would have received lethal doses of radiation. In addition, they had carried out the heat measurements in a way which was known to be susceptible to systematic errors.

Apart from these scientific warning signs, many of their colleagues were extremely suspicious of the way in which the results obtained by Pons and Fleishmann were communicated to the scientific community. They had worked in unusual secrecy for a number of years, not even involving the nuclear physics department at Utah. Then their results were not revealed to the world through a peer-reviewed journal article, as is the norm, so that it didn't form part of the academic system designed to promote the excellence of science by allowing qualified experts to check your account of your work before publication. The details given at the press conference were vague, and that didn't make it easy for others to check the results, by reproducing and trying to understand their work. When their academic paper came out, it had been allowed to bypass the peer review procedure, and not only was it also vague, but its account contradicted what had been said at the press conference. It contained so many mistakes that the errata published in the next issue of the journal where it appeared amounted to a quarter of the length of the original article (and even included the name of another author who had been omitted from the first publication).

The politics of the announcement were also mishandled. The University of Utah insisted that crucial details were kept secret, so as not to prejudice a future patent application. Dissatisfaction among the scientific community was met with accusations that the science establishment was biased towards the prestigious establishments in the eastern US which received the largest government grants toward research projects. Applications were made to both Federal and Utah State government bodies for funds outside of the normal mechanism for grant making (which involves peer review of proposals).

So why did cold fusion polarise the scientific community, given the many flaws listed above (and more became apparent as time went by)? The main reason seems to be that its proponents were blinded by the potential benefits should the claims have proven to be true. Basically, these included an end to the energy crisis, with virtually inexhaustible power available for a tiny cost. People wanted to believe in it, and so tended to interpret experimental results in a way that bolstered the possibility of cold fusion.

As chairman of the DOE committee, whose unfavourable report was instrumental in the Federal decision not to formally support cold fusion research, John Huizenga was strongly attacked by the supporters of cold fusion. He could hardly be expected to be positive about it, but he very carefully refrains in this book from going beyond purely scientific criticism of the results a nd methods of those involved. He does occasionally resort to rather inflammatory language, as for example when he describes an attempt to explain cold fusion as a 'non-theory' resting on a series of 'miracles'. (In fact, what he means by the word miracle, distinctly pejorative in a scientific context, is an unsubstantiated hypothesis contrary to generally accepted scientific ideas, such as an altered probability of a particular type of deuterium fusion.)

Bias is possibly present, though I think this is as a result of the treatment Huizenga received, but not prejudice. The book is a useful summary of the history of cold fusion and an examination of its scientific credentials. What grated with me was one particular aspect of the writing style - it is very repetitive. Huizenga repeats the same criticisms of cold fusion experiments in chapter after chapter, to the point that they read like a series of more or less independent articles on the subject. I suspect that this is partly because he had made these criticisms over and over again to cold fusion supporters without them being answered, preferring to launch personal attacks upon him and other sceptical scientists instead.

Roger Penrose: The Emperor's New Mind (1989)

Edition: Oxford University Press, 1989
Review number: 283

It is easy to lose track of what The Emperor's New Mind is about. It is intended as an examination of the claims of 'strong AI' from a fairly sceptical viewpoint (as the title indicates). The style aims at popular science, but it is difficult to follow and occasionally, I suspect, dauntingly full of complex mathematics (as a mathematician myself, I find this a little difficult to
tell).

The strong AI position is basically that it is possible for a sufficiently complex computer program to mimic the workings of an intelligent mind. In computer science terms, this is more precisely expressed by saying that the workings of the mind are algorithmic or computable in nature. Penrose's book naturally starts, then, with an explanation of these terms, together with a discussion of related ideas by Turing (the famous Turing test, and the Turing machine, which is one of the more accessible ways to define computability). He also talks about results showing that there are concepts which are not algorithmic in nature: the halting problem (there is no algorithm to determine in general if a computer program will ever complete its task) and Gödel's incompleteness theorem (which implies that there is no computer program which can mechanically prove every mathematical result about arithmetic). This first section ends with a digression into the lambda calculus, an alternative formulation of computability, which is extremely difficult to follow.

The second - and longest - section of The Emperor's New Mind is an exposition of the physics that Penrose expects to lie behind the aspects of the mind that would be non-algorithmic: quantum mechanics and, in particular, the resolution of the differences between quantum mechanics and relativity. (This is one of the most important and most difficult problems in modern theoretical physics.) He postulates that the way this incompatibility will be overcome will involve the incorporation of an asymmetric time element into the theory, and this requires a discussion of thermodynamics and entropy. (The question of why time appears to flow and many events seem irreversible when the major physical theories behind them are indifferent to the direction in which time flows is another important problem in today's physics.)

It is in this section, dealing admittedly with three of the most notoriously difficult parts of physics, that the limitations of Penrose's ability to write for the layman become apparent. His explanations seem to simplify in the wrong places, and complex mathematics is presented without sufficient textual exposition to make it palatable. He has not a great deal of space, but does tend to digress to explore areas of the theory that he finds interesting, but which are not relevant to his main theme. That would be fine in a book about quantum mechanics, for instance, but is misplaced when quantum mechanics is being introduced for another purpose.

Following a brief description of the physical construction of the human brain and some experiments to do with consciousness, Penrose rounds off the book with his explanation of how the brain might work, contrasted with the ideas of strong AI enthusiasts. He is not in fact particularly concerned to detail reasons for finding strong AI unlikely, but is more interested with coming up with a physical description of consciousness which would be intrinsically non-algorithmic in parts. He does list some arguments against strong AI, including a most interesting couple of pages about mathematical thought, often considered to be one of the most strongly algorithmic modes of consciousness (because mathematical writing uses a style which can make proofs look rather like algorithms).

The level of detail into which Penrose goes when explaining quantum mechanics and general relativity is unnecessary, and he would perhaps have been well advised to cut this section of the book considerably, expanding the final discussion about intelligence and consciousness instead. That discussion is, after all the main point that Penrose wants to make, the reason why he wrote the book. It is also the most interesting and lucid section. If you already know something about relativity and quantum mechanics, the rest of the book may well seem fascinating, but it cannot be recommended as an introduction to either subject.

If I have been rather critical of Penrose's writing, it is not because I disagree with his position on strong AI, but because I feel that his style is not suited to a popular approach. (I would tend to think strong AI unlikely on intuitive grounds - the way I think and feel doesn't seem mechanically determined to myself - and therefore I would say that the burden of proof lies with its proponents.)

Steven Weinberg: Dreams of a Final Theory (1992)

Edition: Radius, 1992
Review number: 149



Steven Weinberg, winner of the Nobel prize in physics for his work on elementary particle theory, wrote this book while involved in the campaign by American physicists to obtain a grant for the Superconducting Super-Collider (SSC). This campaign colours the book, a lot of it being Weiberg's responses to the type of questions both physicists and non-physicists asked about the project and its aims, or an outcome of his own background thought as he marshalled his arguments for his testimony to the Congress committee involved.

Because of the nature of the project, however, the book goes far beyond arguments for one particular particle accelerator. For the SSC was intended to test theories of the fundamental nature of the universe in which we live, to help physicists formulate a final theory, or "theory of everything". Thus the kind of questions which are being asked include: What do physicists mean by a final theory? What indications are there that such a theory may exist? How close are we to one? What sort of things might such a theory say? How could we tell it is indeed final? What would be the role of God in a universe governed by such a theory?

The last question is the one which is always asked by non-physicists, though it is perhaps not so interesting as some of the others, from either a philosophical or scientific viewpoint. Weinberg has written this book as an attempt to answer all these questions from the point of view of a professional physicist; he doesn't pretend to a vast understanding of the academic philosophy of science, the vast majority of which is seen as of no use or interest to those involved in scientific research. Indeed, some sociological analyses of science are positively inimical to the practice of research, because they assert that accepted scientific theories are a purely human construct, with no relationship to "truth" or "reality" (whatever these terms may be taken to mean). There clearly is some cultural influence on devising and interpreting experiments, but there is no motivation for doing so if you believe that there is no other factor involved. Such sociological theories have the same problem as naively expressed logical positivism - their pre-suppositions are destroyed by their application to themselves. In other words, the idea that scientific research is a cultural phenomenon should apply to itself, assuming that sociologists believe that what they do is scientific (and I believe that they do). (The statement that has the same problem in logical positivism is the idea that only verifiable statements should be considered as true - a statement which is not verifiable.)

The fact that in the end the battle for continued funding for the SSC was lost does not mean that this is a book only of interest in the mid-nineties. In the end, the debate was more an example to be quoted in the book and a motivation for writing it than its absolute centre; the questions it raised and Weinberg's discussion are of far wider interest.

Abraham Pais: 'Subtle is the Lord...' (1982)

Edition: Oxford University Press, 1982
Review number: 63


Subtle is the Lord... (the Einstein quote finishes "...but he is not malicious") is an excellent biography of Albert Einstein written by an eminent physicist. A fair knowledge of physics is necessary to read this, but reading a biography of Einstein which doesn't convey the work that he did is much less interesting to those who have such a knowledge.

Pais is not uncritical of Einstein. A major theme of his book is to answer the question of why, after the major achievements of special and general relativity and his quantum mechanics papers, Einstein produced so little work of permanent value in the second half of his working life. In fact, Pais suggests that the very aspects of Einstein's character which made the earlier breakthroughs possible meant that his work became more divorced from the mainstream of twentieth century theoretical physics as time went on.

Subtle is the Lord is rather less interested in the non-physics related activities of Albert Einstein, though considerable space is given to his pacifism and Zionism. There are other biographies which concentrate on these matters, and are much more interested in Einstein's private life. Pais' work is where to come for a definitive description of the way in which Einstein's work and life fitted together.

Richard P. Feynman: Surely You're Joking Mr Feynman - Adventures of a Curious Character (1985)

Edition: Vintage, 1992
Review number: 22
 
As the subtitle suggests, this is the story of an unusual man, a Nobel Prize winning physicist who worked on the atomic bomb who was also an amateur artist who had a successful one man show - among many other talents. It is an interesting read, even to those who (like me) don't normally enjoy (auto)biographies.

The book presents an honest picture of Richard Feynman, based mainly on taped conversations with a friend. This means that his personality comes through strongly, showing both the admirable traits and the less than admirable traits. I didn't like Richard Feynman practical joker, but found Richard Feynman indefatigable science educator more to my taste. (I particularly enjoyed the story of his evaluations of school physics textbooks for the state of California.)

As well as thinking that people in general could benefit by better understanding of science (and better science education), I also think that many scientists would benefit from being able to write as well as Feynman, and the public would probably have a better understanding of science if they did!