Lee 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.
on 21 December 2014
Physics has encountered a tough problem in explaining why the fundamental constants which define the masses, charges and interactions of particles have the values they do. This impasse, decades in duration, was analysed by Lee Smolin in his 2006 book, "The Trouble with Physics".
Foremost among attempts at its resolution are schemes containing a plethora of universes, possibly an infinitude, of which our local one just happens to be the way it is; if it weren't we would not be here to wonder about these things. Hardly a falsifiable proposition, and therefore not scientific, as Smolin points out.
Mind you, his preferred scenario is also replete with universes, though in his universes a selection mechanism is at work which zones in on our particular cosmic environment as a fruitful one for propagation of more universes via black holes. Cosmic "genes" (fundamental constants, initial conditions) that are good for production of black holes are good also for galaxies, stars, planets and, ultimately, us. This theory is at least capable of making predictions which are falsifiable (or not) using available data sources.
Time is implicit in his hypothetical process. But universal time is associated with the concept of simultaneity which is ruled out by relativity. Smolin and his associates are working on a resolution of this conflict which might, as a bonus, explain non-local aspects of quantum entanglement without invoking the notorious hidden variables which have themselves been pretty well ruled out by clashes with Bell's theorem.
So far, nothing has come of this approach, though the reality of time is supported by the emergence of complexity in a universe which should by rights be heading for equilibrium. The discussion of how this happens through the intervention of gravity and the effective re-setting of entropy's clock when stars light up is fascinating and rewarding to read.
But, apart from a few such illuminating insights, this book makes tedious reading. It suffers from poor style, lack of conciseness in presentation of ideas, sloppy diagrams and a great deal of repetition. The epilogue is a rambling discourse upon life, the universe and everything, including subjects as diverse as ecology, economics, moral values, the origin and nature of consciousness - even global warming. Read this section first and you might save yourself an awful lot of time.
on 24 May 2013
Lee Smolin has truly made a book that does make you think very differently about time. His arguments are provocative and perhaps controversial but that is a good thing. I love that his emphasis is always on making his theories as amenable to experiment as possible. Having read the book I am especially swayed by his arguments about trying to build a cosmological theory that is not based on what he calls the "physics in a box" theories which always involve boundary conditions. The most important thing about this book is that it is easy to read and engaging. Another reviewer was horrified that he was promoting a nonlocal hidden variables theory, but at least he has made a justification for it and his focus is always in trying to build such a justification for a new theory that will be experimentally falsifiable. I also rather like his ensemble-interpretation of quantum physics because it at least is trying to make the theory based on real-ensembles. Almost throughout the book this falsifiability is his main commitment, and if it was throughout the whole book then I would have given it 5 stars. However, he recapitulates in the epilogue and claims that there are things that are probably "intrinsic" and "essence-like" and seems to hark back to dualist and unfalsifiable theories of consciousness. Though this is a tiny section of the book it scares me that he would build such a wonderful relational justification for the universe and then discard it because he can't "see" how consciousness would fit into it. He drives a difficult path through the mire and then seems to jump on an easy one at the end for a bit of light relief! It is difficult to imagine a relational and heterophenomenological theory of consciousness, but just because it is difficult to imagine is no argument against it, and certainly should justify believing in essences! He was admittedly coy about even delving into this topic and I just wish he hadn't. It seemed to come out of nowhere. In the rest of the book he argues very well that people have been stuck in a rut and think about physical theories in a dubious way, and I think is argument is important and should be well-read. I also like his arguments for things having an actual history and evolving being a very important criteria in science - as else we are effectively presuming timelessness. His main thesis is certainly very palatable, and deserves serious attempts to falsify it. One of the most exciting sections of the book is the section on shape dynamics - theories which are equivalent to general relativity but in which size is not absolute, but relative, yet which also has a preferred time slicing. A wonderful idea. In summary: read this book, just be careful with the epilogue!
on 26 April 2013
Professor Lee Smolin argues that we need to move away from 'timeless' theories of physics and put 'now' back where it belongs, at the centre of our theories, just as it is at the centre of our experience. This, he maintains, will allow progress in quantum theories beyond the discomfiting and untestable notion that we live in an infinite multiverse, where anything that can happen does happen, an infinite number of times. Exciting stuff, presented in a non-mathematical way that does not presume an extensive knowledge of physics. Einstein found 'now' puzzling... I guess he might approve of this approach.
on 16 January 2014
Lee Smolin is a researcher at the Perimeter Institute in Canada and considers low level issues in physics like why it's so hard to formulate gravity in a quantum framework. He's also a bit of an outsider because he thinks modern physics hasn't really progressed in 30 years. Sure we have light emitting diodes and smartphone but there's been no change in fundamental physics. For example, the theoretical under-pinnings of the recently discovered Higgs boson were written down 50 years ago.
So in the book Smolin advances his view of a possible alternative formulation of fundamental physics which he believes will allow progress to be made. Core to this alternative formulation is our perception of time as an eternal, outside constant. This is why the book has the name it does. He's not proposing to rewrite general relativity or quantum mechanics he's just suggesting looking at these pillars from a different perspective.
If you are into physics and want a non-establishment view of current ideas and research in physics this will be a good read for you.
on 27 May 2013
Lee Smolin examines the possibility that our universe is the product of some kind of natural selection involving black holes and/or cyclic Big Bang/Big Crunch scenarios. Like Ilya Progogine, he maintains that the future is uncertain to some extent and amenable to human influence here on Earth, so we should take seriously our responsibility for reducing global warming for example. Entanglement could be explained if the holographic nature of our 3D reality is based on information stored on a quasi 2D surface, analogous to the event horizon of a black hole. By reinstating time, Lee makes a good attempt to bridge the gap between what Einstein's relativity and quantum theory say about the nature of reality.
on 22 January 2015
I thought that Lee Smolin's "The Trouble With Physics" was a timely and important critique of string theory's dominance of the research agenda in fundamental physics, given that it has failed to deliver - or even progress towards - testable predictions about reality. I was looking forward to his new book, which purports to offer some new approaches which might start to bring theory back on an intercept course with experiment.
Central to Smolin's proposed new approach is the idea that time is "real", in the sense that there is such a thing as "the present moment", which is qualitatively different from the future and the past, independently of any observer perceiving it to be so. The fact that pretty much all scientific advances since Gallileo have suggested the contrary (that all moments are equally real and it is a subjective experience that the present moment is fundamentally different from those that have gone before or are yet to come) is, Smolin suggests, a mistaken notion that is holding scientific progress back.
Smolin offers no data or experiment to support this conclusion, but merely a set of logical and linguistic arguments - Time Reborn should therefore really be classed more as philosophy than science. Unfortunately, Lee Smolin is not a good philosopher, and his arguments turn out to be a house of cards built on flimsy foundations.
Things start off badly when Smolin hints at a sympathy for platonism - a 2400 year old metaphysical system basically expressing Plato's inability to comprehend the concept of an abstraction. Much ink is dedicated to what Smolin calls the Newtonian Paradigm of science - experiments performed repeatedly on isolated systems from which conclusions are drawn about the underlying laws that are operating. Smolin suggests that because a system can never be truly isolated (it is always at least gravitationally affected by its environment), anything we conclude from such experiments can be at best an approximation to a fundamental "law" because there will always be other factors at play. He seems either not to understand or to be skeptical of the idea that what remains true across multiple repetitions and in many environments is deduced to be an underlying law, even though any specific experiment is always going to be affected by other factors. This is reminiscent of Plato's failure to understand that an abstraction is basically just grouping objects by their commonalities and ignoring their differences. It cannot and does not try to capture every single detail of specific concrete objects. Similarly, scientific "laws" do not purport to capture every aspect of a system, but hopefully to model what is common between them. To conclude (as Smolin does) that there can be no such thing as a universal law because there is never a perfectly isolated system that embodies it seems to rather miss the point.
Smolin further suggests that physics has hit a roadblock because it tries to apply the Newtonian Paradigm to cosmology (the study of the whole universe), but fails because the universe cannot be isolated (from the observer, at least) or repeated. Smolin criticises scientists for trying to apply a method which works on small parts of the universe to the universe as a whole, but then repeatedly commits the equivalent philosophical error - many of his arguments boil down to logical arguments constructed in domains where the words used cannot reasonably be assumed to apply - broadly what would be called a "category error". Just because we can ask "What was happening before time began?" it does not mean there must be an answer, for instance (Smolin's arguments are not so crude, but often resolve to a similar misuse of logic).
It is Leibniz that gets the most name checks in the book though, with Smolin citing several of the philosopher's principles as guides. The Principle Of Sufficient Reason is the first pillar on which Smolin attempts to construct his cosmology, though I am not sure Leibniz would condone Smolin's interpretation of it. Starting from his Principle of Sufficient Reason and through dubious logical gymnastics Smolin deduces a series of principles which he believes a valid cosmological theory must embody. At each step he seems to try to make the case that reconceiving time as fundamental and "real" both implies and is implied by his arguments, though I don't think he ever makes a convincing case for it either way.
Time Reborn starts off pretty unconvincing and gets even more so as it goes on. By the midpoint it had become a real slog to get through, as Smolin deduces new conclusions and principles from arguments he has failed to convincingly make earlier. It all comes across as sophomoric philosophical speculation with little or no connection with scientific experiment. By the time Smolin is basing his arguments on things like a "Principle of no unreciprocated action" that he basically pulls from nowhere (just the observation that it worked for Einstein - I don't think it was a major motivation for General Relativity, to be honest) he might as well just be filling the page with the word "bibble". At one point he suggests that a new understanding of quantum mechanics might be based on a "principle of precedence" - essentially that the universe makes up the results to any given experiment as it goes along, constrained only by the rule that it must be consistent with the results of previous experiments. How such consistency is enforced is never even speculated about, and no method by which we could prove that the result of an experiment we have never performed was undetermined before we performed it is suggested. It seems basically to be motivated by a desire to show that the future is "open", in that novel events can happen which are not determined by the history of the system, and therefore that humans might have "free will", because that would be nice. Maybe, but it's not science.
I do agree that string theory has taken physicists on a detour down what is looking increasingly like a blind alley, and that fresh new ideas are needed to get the discipline back on a productive course. Those ideas have to be driven by the data though - theories which can explain the data we already have better than existing theory, or ideas for novel experiments that might yield fresh leads. Second rate philosophy and speculation ain't going to do it.
The aim of the book is to restore time to its `rightful' place as a `real' quantity in the description of the universe. For most readers, and also most scientists (despite what Smolin says) time is already `real'; we observe its passage daily as things, including ourselves, decay. On the other hand, there is the paradox that although we live `in time' we commonly judge our activities by timeless standards; Smolin gives `truth' and `justice' as examples. In the scientific context, what he means is not that the laws of nature don't contain a time variable, because some of them obviously do, rather the form of the laws themselves are timeless. Newton's laws of motion are the same now as when he discovered them and will remain so indefinitely; that is the assumption on which physical science at present is based. Progress within this framework is made by making improvements to experiments and treating the outcomes as timeless. Smolin starts by reviewing how this has become the orthodox view.
Smolin believes that the orthodox view is an illusion that stems from a common belief (the Newtonian paradigm) which assumes we can predict the future state of any system from its initial conditions and the laws acting on it and, crucially, that this can be extended to the universe as a whole. One consequence of this is that the universe would ultimately reach equilibrium where entropy is maximized and a universe such as ours could occur only briefly as a random fluctuation, which leads to some very weird predictions and essentially renders scientific research pointless. Smolin believes the Newton paradigm is a fallacy, because in practice physics deals with closed systems, and we have to accept that the laws as we know them are approximations. In his view everything can evolve, including the laws of nature. He also believes that the conventional viewpoint has led cosmology into its present dilemmas and that by restoring time, a new cosmological theory might emerge that will satisfy Leibnitz's `principle of sufficient reason', i.e. there has to be a rational answer to any reasonable question that we may ask about why the universe has some particular feature. He shows that such a theory would have no symmetries or conservation laws and the outcome of future experiments would be determined by the collection of past cases. Needless to say, these are very radical ideas, and it will take a lot of evidence to persuade the vast majority of physicsists of their correctness. Although at present there is not a scrap of evidence to support these ideas, one has to admire Smolin for still insisting that any new theory would require experimental verification, contrary to some theorists who, out of frustration one feels at not being able to think of suitable experiments, advocate `following the maths' and going where it leads. Interestingly, Smolin thinks that maths may actually be inhibiting the development of a new cosmological theory.
I am not sure for whom this book was written. The subject is very esoteric, even for particle physics/cosmology, and to understand Smolin's views, which are very unorthodox, requires much concentration and thought. It is certainly not for the fainthearted and cannot really be classified as `popular science'. It is not helped by his repetitive style of writing, some very poor hand-drawn diagrams and his tendency to wander off the point. Having said that, he does make one think about things that are usually taken for granted.
on 6 October 2014
In this remarkable book Lee Smolin carefully builds the case for adopting time rather than space as the fundamental property of the universe. The principal models which describe the physical behaviour of material, Newtonian, relativistic and quantum mechanics agree very well with experiment but do not give completely consistent accounts of experimentally observed reality because they model isolated systems. A truly fundamental description of physical reality must take into account the rest of the universe in which we exist. By considering the dynamic behaviour of material in an unbounded universe Professor Smolin concludes that there is good reason to expect that a consistent account of reality can be achieved if we accept the reality of absolute time and space as an emergent property. The case for this approach is beautifully made without recourse to mathematics and the author shows that it leads to experimentally testable conclusions. Despite the absence of maths the book is not an easy read because the arguments are detailed, but the writing is lucid. I find the book both enjoyable and exciting because it offers the hope of progress in deepening our understanding of reality.
on 12 July 2015
The first book I've read by this author.I won't go into details but it is accessible to the general science reader and is less complex than other books on the subject of hidden variables.
If you think time is to do with clocks and measurement of change you should find something else to read.