The Singular Universe and the Reality of Time: A Proposal in Natural Philosophy 1st Edition

This is a superb and important book. It is quite long and two books in one, the first by Roberto Unger and the second by Lee Smolin. Both address the same topic, the reality (and fundamentality) of time and the failure of the Newtonian paradigm when applied to the whole universe. Each author takes a different approach to the subject on which, for the most part, there is a wide area of agreement between them and a few differences as concerns some details.Neither book is "popular science", but rather both are serious attempts at a novel "natural philosophy" that contributes (or should contribute) to advancing the subject of cosmology by illuminating little considered implications and interpretations of the physical (standard model) and cosmological data we already have.Unger's approach is more purely philosophical. He begins straightforwardly enough with the common (in science) metaphysical assumption that only the material universe is real. Although he abjures a strong metaphysics and offers instead what he calls a "proto ontology" that does not attempt to fix the kinds of things there are in the universe for all time, he is nevertheless stuck with this basic materialism and that forces him onto one of two horns of a dilema. The mystery is the extreme unlikeliness of "the settings" that make the universe hospitable to life. Most physicists being philosophically trapped in the "block universe" model of relativistic time (which in effect denies the fundamentality of time by casting time in terms of spatial geometry) have gone over to the multiverse as an (untestable) explanation (along with the "anthropic principle) for the unlikely values of the settings in our universe. From Unger's viewpoint, the opposite tack, assuming time to be both real and fundamental, and that there is a global "preferred time" (perfectly compatible with relativity given appropriate alterations in what Unger calls its "metaphysical gloss") which all means that there is nothing in the physical universe that is immune from the effects of time including the laws and settings which change (albeit in this universe phase very slowly) and that instead of multiple universes, the unlikeliness of our settings is explained by our one universe having an indefinite (not eternal) past that has gone through phases having various settings and has just happened, in this phase, to end up with the settings it has. Unger believes that this option, the "indefinite past" and a single universe at a time is better than the multiverse hypothesis because it provides for a causal (although the laws governing causal interactions will be different from phase to phase) continuance between phases. Time and causation entail one another, they are both fundamental in that what ever the laws and settings operative at a given moment happen to be, there is still some sort of causal interaction in time. As difficult as it might be to detect records of past universe phases (that is prior to our own big bang) such detection remains possible and therefore within the scope of science, while non-communicating multiverses that preclude any interaction do not.Unger covers his ground very well. His approach is to revisit the same questions and issues over and over again like a skeleton on which he lays a little more flesh with each pass. In the end he leaves out two things. He offers no specific explanation for our particular settings this time around, and he fails to address how it is that the laws and settings we measure in our universe phase happen to hold over a range of conditions from the cold of interstellar space to the interior of stars. He admits that in our present "cooled down" universe the laws and settings appear very stable. His failure to offer any explanation for their stability does not detract from the argument that time is real and there is only one universe at a time. He explicitly leaves the rest to Lee Smolin.Smolin is a physicist writing here as a natural philosopher and he is very good at it. His argument here is a reprise of his book "Time Reborn". He's had a few years to chew over these ideas, and I think his more concise treatment here is clearer than it was in that book. Smolin does offer two possibilities for explaining what Unger leaves out. The first is his "principle of precedence" which goes only part of the way, explaining how it is that the settings might get set, but not why they are what they are. The second, his notion of "cosmological natural selection" does actually explain both the settings and to some extent their stability across the wide range of conditions in our present universe. But these explanations rely on two rather speculative ideas.First, new universes arise from the interior of black holes. The point of the settings and their stability is that these two properties are necessary to produce lots of black holes from massive stars. Such black holes in effect set the parameters of the universes they generate. Our own universe is in fact such a baby universe generated by a black hole in another universe. Second, the range of possible (or likely) settings of the baby universe would be different than those of the parent universe but only and always in a small range. This is what sets up the "natural selection".. Universes whose properties happen to produce a lot of those kinds of black holes will end up dominating a history of branching universes such that the great majority of them have settings similar to ours just so that they can produce a lot of black holes.Of course the very idea that universes are born in black holes (or that ours emerged from a black hole) is at present utterly beyond observational science, so this is sheer speculation whose only relation to physics (as distinct say from asserting that "God did it") is that there is a potential causal chain (no matter what transformation the settings might undergo in between) connecting parent (black hole) to child (new universe). Smolin fails to say why it is that the variation in settings through black holes from massive stars (he explicitly rejects primordial black holes as selectable parents for this reason) should vary by only a little.This property is what makes them selectable. If the settings vary by very much, the outcomes (as far as black hole creation are concerned, not to mention life) will be random and not converge to an optimal type. There is no mention here that the coincidence of these same settings being conducive to life AND black holes is itself something of a mystery. Dr. Smolin spends a small chapter addressing the nature of qualia in consciousness, but he is interested in suggesting an example of precedent-agnostic causation (brain correlates of qualia) and not the coincidence of settings conducive to both black holes and life.Both men address "the unreasonable effectiveness of mathematics", and claim, reasonably enough given their history-first foundation, that present mathematics happens to be fit-able to present physics but that the discipline has no magic insight into the nature of every particular event in the history of the universe (Smolin) or into some Platonic structure that is metaphysically prior to actual history taken in aggregate (Unger). This is one of the more fascinating parts of both arguments because both men get to the same place about math in very different ways.It is unfair to criticize either author for not solving every problem. For both this book is to be the foundation of a natural philosophy, not its completed edifice. Both author's arguments rest on a foundation of time, causation, and therefore history as being fundamental. The universe is what it is and if we discover structure in its behavior, that structure, mathematically describable regularities, it doesn't mean those very regularities weren't different in the past and won't change in the future. There is every reason to believe they are both onto something here. Smolin's illustration of how we slip from an observation of causal stability in the present universe to a mistaken notion of absolutely deterministic precedents is illuminating to say the least. All of this above does not do justice to the over-all philosophical integrity of this work. Drs. Unger and Smolin happen to discover in one another kindred spirits as far as this business of the reality and fundamentality of time is concerned. I hope there will be more collaborations between them in the future.

In his 2013 book  Time Reborn , Lee Smolin argued that, despite its extraordinary effectiveness in understanding the behaviour of isolated systems, what he calls the “Newtonian paradigm” is inadequate to discuss cosmology: the history and evolution of the universe as a whole. In this book, Smolin and philosopher Roberto Mangabeira Unger expand upon that observation and present the case that the current crisis in cosmology, with its appeal to multiple universes and mathematical structures which are unobservable, even in principle, is a consequence of the philosophical, scientific, and mathematical tools we've been employing since the dawn of science attempting to be used outside their domain of applicability, and that we must think differently when speaking of the universe as a whole, which contains all of its own causes and obeys no laws outside itself. The authors do not present their own theories to replace those of present-day cosmology (although they discuss the merits of several proposals), but rather describe their work as a “proposal in natural philosophy” which might guide investigators searching for those new theories.In brief, the Newtonian paradigm is that the evolution of physical systems is described by differential equations which, given a set of initial conditions, permit calculating the evolution of a system in the future. Since the laws of physics at the microscopic level are reversible, given complete knowledge of the state of a system at a given time, its past can equally be determined. Quantum mechanics modifies this only in that rather than calculating the position and momentum of particles (or other observables), we calculate the deterministic evolution of the wave function which gives the probability of observing them in specific states in the future.This paradigm divides physics into two components: laws (differential equations) and initial conditions (specification of the initial state of the system being observed). The laws themselves, although they allow calculating the evolution of the system in time, are themselves timeless: they do not change and are unaffected by the interaction of objects. But if the laws are timeless and not subject to back-reaction by the objects whose interaction they govern, where did they come from and where do they exist? While conceding that these aren't matters which working scientists spend much time thinking about, in the context of cosmology they pose serious philosophical problems. If the universe all that is and contains all of its own causes, there is no place for laws which are outside the universe, cannot be acted upon by objects within it, and have no apparent cause.Further, because mathematics has been so effective in expressing the laws of physics we've deduced from experiments and observations, many scientists have come to believe that mathematics can be a guide to exploring physics and cosmology: that some mathematical objects we have explored are, in a sense, homologous to the universe, and that learning more about the mathematics can be a guide to discoveries about reality.One of the most fundamental discoveries in cosmology, which has happened within the lifetimes of many readers of this book, including me, is that the universe has a history. When I was a child, some scientists (a majority, as I recall) believed the universe was infinite and eternal, and that observers at any time in the past or future would observe, at the largest scales, pretty much the same thing. Others argued for an origin at a finite time in the past, with the early universe having a temperature and density much greater than at present—this theory was mocked as the “big bang”. Discovery of the cosmic background radiation and objects in the distant universe which did not at all resemble those we see nearby decisively decided this dispute in favour of the big bang, and recent precision measurements have allowed determination of when it happened and how the universe evolved subsequently.If the universe has a finite age, this makes the idea of timeless laws even more difficult to accept. If the universe is eternal, one can accept that the laws we observe have always been that way and always will be. But if the universe had an origin we can observe, how did the laws get baked into the universe? What happened before the origin we observe? If every event has a cause, what was the cause of the big bang?The authors argue that in cosmology—a theory encompassing the entire universe—a global privileged time must govern all events. Time flows not from some absolute clock as envisioned by Newtonian physics or the elastic time of special and general relativity, but from causality: every event has one or more causes, and these causes are unique. Depending upon their position and state of motion, observers will disagree about the durations measured by their own clocks, and on the order in which things at different positions in space occurred (the relativity of simultaneity), but they will always observe a given event to have the same cause(s), which precede it. This relational notion of time, they argue, is primordial, and space may be emergent from it.Given this absolute and privileged notion of time (which many physicists would dispute, although the authors argue does not conflict with relativity), that time is defined by the causality of events which cause change in the universe, and that there is a single universe with nothing outside it and which contains all of its own causes, then is it not plausible to conclude that the “laws” of physics which we observe are not timeless laws somehow outside the universe or grounded in a Platonic mathematics beyond the universe, but rather have their own causes, within the universe, and are subject to change: just as there is no “unmoved mover”, there is no timeless law? The authors, particularly Smolin, suggest that just as we infer laws from observing regularities in the behaviour of systems within the universe when performing experiments in various circumstances, these laws emerge as the universe develops “habits” as interactions happen over and over. In the present cooled-down state of the universe, it's very much set in its ways, and since everything has happened innumerable times we observe the laws to be unchanging. But closer to the big bang or at extreme events in the subsequent universe, those habits haven't been established and true novelty can occur. (Indeed, simply by synthesising a protein with a hundred amino acids at random, you're almost certain to have created a molecule which has never existed before in the observable universe, and it may be harder to crystallise the first time than subsequently. This appears to be the case. This is my observation, not the authors'.)Further, not only may the laws change, but entirely new kinds of change may occur: change itself can change. For example, on Earth, change was initially governed entirely by the laws of physics and chemistry (with chemistry ultimately based upon physics). But with the emergence of life, change began to be driven by evolution which, while at the molecular level was ultimately based upon chemistry, created structures which equilibrium chemistry never could, and dramatically changed the physical environment of the planet. This was not just change, but a novel kind of change. If it happened here, in our own recent (in cosmological time) history, why should we assume other novel kinds of change did not emerge in the early universe, or will not continue to manifest themselves in the future?This is a very difficult and somewhat odd book. It is written in two parts, each by one of the co-authors, largely independent of one another. There is a twenty page appendix in which the authors discuss their disagreements with one another, some of which are fundamental. I found Unger's part tedious, repetitive, and embodying all of things I dislike about academic philosophers. He has some important things to say, but I found that slogging through almost 350 pages of it was like watching somebody beat a moose to death with an aluminium baseball bat: I believe a good editor, or even a mediocre one, could have cut this to 50 pages without losing anything and making the argument more clearly than trying to dig it out of this blizzard of words. Lee Smolin is one of the most lucid communicators among present-day research scientists, and his part is clear, well-argued, and a delight to read; it's just that you have to slog through the swamp to get there.While suggesting we may have been thinking about cosmology all wrong, this is not a book which suggests either an immediate theoretical or experimental programme to explore these new ideas. Instead, it intends to plant the seed that, apart from time and causality, everything may be emergent, and that when we think about the early universe we cannot rely upon the fixed framework of our cooled-down universe with its regularities. Some of this is obvious and non-controversial: before there were atoms, there was no periodic table of the elements. But was there a time before there was conservation of energy, or before locality?

A follow-up to Smolin's 'Time Re-born', this volume attempts to establish a triple thesis: the case for there being only one universe; that time is real; and that mathematics is, though a useful scientific tool, is not homologous to (i.e. cannot totally mirror) the universe. Though the first part (by Unger) is somewhat repetitive at times, it nonetheless does an excellent job of providing the philosophical underpinning of the triple thesis. The second part (by Smolin) is more pithy, if at times a tad scientifically challenging for the lay reader. Still, all in all, the joint author's have done yeoman service in providing the foundation of a new - and more quintessentially - scientific cosmological project. A solid and sobering counterargument to the mysticism and fanciful maunderings of the 'multiverse' crew.

Probably the most complex book i have read in a long time.It assumed a fair level of initial knowledge in both Physics and Philosophy but if you can do the work then the ideas that are discussed within this text are well worth itIn particular is the treatment of Mathematics and the discussion about it not being the fundamental science and his treatment of the infinite as being purely a mathematical work around that we should always keep in mind does not reflect anything real in the universeIt took me a long long time to get through this text, but highly worth the effort

There seems to be too much repetition. I am in no position to comment on the content. I enjoyed readng it

I thought it was a Smolin book, but it's not. Full of cheap philosophy, and not a single equation, at least in Mangabeira's half. Dumb ideas such as "laws that change": any "changing law" is part of a higher level law. Even a Brazilian philosopher should know that.

New perpective...the historical view and constant change of even "immutable laws" makes sense. The view of time/space is different, and my own thoughts are time exists due to space, and vis versa, but the concepts are coherent, necessary for conceptual progress, and intriguing. Bravo, Mr Mangabeira Unger and Mr. Smolin, a work of eminence. Enjoyable read and brain flex.