Lee Smolin’s 00:00 Time Reborn, Allen Lane 2013, ISBN 9781846142994: A curious read, as I, too, was off-put by the development of the first section in believing LS would actually agree with the “No Time’rs”, ploughing on with No! No! You can’t seriously mean that! when suddenly LS makes a u-ey and explains how things actually are. And then, unfortunately, ends with an almost delirious account on the edge of philosophy – before caving in to e.g., religion. An unfortunate afterburner where the twist to that, should’ve been straight ahead into hermeneutics.
But then again, here we have the, not really representative quotes:
Anyone who thinks that the correct theory of politics or economics was written down in the century before last is thinking outside of time. (p.XV)
We reenter time when we realize that every feature of human organization is a result of history, so that everything about them is negotiable and subject to improvement by the invention of new ways of doing things. (p.XVI)
On a personal level, to think in time is to accept the uncertainty of life as the necessary price of being alive. To rebel against the precariousness of life, to adopt a zero tolerance to risk, to imagine that life can be organized to completely eliminate danger, is to think outside time. To be human is to live suspended between danger and opportunity. (pp.XVI-XVII)
Could we overcome the capriciousness of life and achieve a state in wherein we knew, if not everything, enough to see all the consequences of our choices – the dangers and the opportunities alike? This is, could we live a truly rational life, without surprises? If time were an illusion, we could imagine this as possible … Some number, some formula, could be computed and decoded to tell us all we needed to know.
But if time is real, the future is not determinable from knowledge of the present. (p.XVII)
Relativity strongly suggests that the whole history of the world is a timeless unity; present, past, and future have no meaning apart from human subjectivity. Time is just another dimension of space, and the sense we have of experiencing moments passing is an illusion behind which is a timeless reality. These assertions may seem horrifying to anyone whose worldview includes a place for free will or human agency. (p.XXII)
Now, a pic, and Moar:
[May have used this Dudok beauty before, H’sum]
This framework views nature as consisting of nothing but particles with timeless properties, whose motions and interactions are determined by timeless laws. … This framework is ideally suited to describe small parts of the universe, but it falls apart wen we attempt to apply it to the universe as a whole. … When we describe a part of the universe, we leave ourselves and our measuring tools outside the system. … Most crucially …, we leave out the clocks by which we measure change in the system. (p.XXIII)
Moreover, a cosmological theory must do without two important aspects of the methodology of science. A basic rule of science is that an experiment must be done many times to be sure of the result. But we cannot do this with the universe as a whole – the universe only happens once. Nor can we prepare the system in different ways and study the consequences. (p.XXIII)
Law is par excellence the thing that wants a reason. (p.XXV)
Laws, then, are not imposed on the universe from outside it. (p.XXVI)
Rather the laws of nature emerge from inside the universe and evolve in time with the universe they describe. It is even possible that, just as in biology, novel laws of physics may arise as regularities of new phenomena that emerge during the universe’s history. (p.XXVII)
Leibnitz formulated a principle to frame cosmological theories called the principle of sufficient reason, which states that there must be a rational reason for every apparent choice made in the construction of the universe. Every question of the form, “Why is the universe X rather than Y?” must have an answer. So if a God made the world, He could not have had any choice in the blueprint. (p.XXVII)
Time must be a consequence of change; without alteration in the world, there can be no time. (p.XXVIII)
As we are quickly coming to realize, biology is about information, and there is no more relational concept than information, … (p.XXIX)
Emergence is an important term in a relational world. A property of something made of parts is emergent if it would make no sense when attributed to any of the parts. Rocks are hard, and water flows, but the atoms they’re made of are neither solid nor wet. (p.XXX)
If space is emergent, does that mean that time is also emergent? If we go deep enough into the fundamentals of nature, does time disappear? In the last century, we have progressed to the point where many of my colleagues consider time to be emergent from a more fundamental description of nature in which time does not appear.
I believe – as strongly as one can believe anything in science – that they’re wrong. Time will turn out to be the only [emphasis added, ed.] aspect of our everyday experience that is fundamental. (p.XXXI)
Mathematical objects are constituted out of pure thought. We don’t discover parabolas in the world, we invent them. A parabola or a circle or a straight line is an idea. (p.7)
Curves and other mathematical objects do not live in time. The value of pi does not come with a date before which it was different or undefined and after which it will change. … Mathematical objects transcend time. (p.8)
One question that Jim and other Platonists admit is hard for them to answer is how we human beings, who live in bounded time, in contact only with things similarly bounded, can have definite knowledge of the timeless realm of mathematics. (pp.9-10)
But what sense does it make to assert that we have reliable knowledge about a domain of nonexistent objects? (p.10)
Galileo’s simple discovery then takes on a transcendental or religious significance: It is the discovery of a reflection of timeless divinity acting universally in our world. (p.11)
Because we have no physical access to the imagined timeless world, sooner or later we’ll find ourselves just making stuff up … There’s a cheapness at the core of any claim that our universe is ultimately explained by another, more perfect world standing apart from everything we perceive. If we succumb to that claim, we render the boundary between science and mysticism porous. (p.11)
It is far more challenging to accept the discipline of having to explain the universe we perceive and experience only in terms of itself – to explain the real only by the real, and the time-bound only by the time-bound. (p.11)
Human being perceive time as change. The time an event takes place is measured relative to other events – for example, the reading of the dial of a clock. (p.12)
If we take this method too seriously, we may be tempted to imagine a clock external to the whole universe, by which we can measure change in the universe. This is the route to a big conceptual mistake, which is to believe that the universe as a whole evolves with respect to some absolute notion of time coming from outside of it. Newton made the mistake because he was caught in the fantasy that the physics he invented captured God’s view of the universe as a whole. The mistake persisted until Einstein corrected it – by finding a way, within relativity theory, to put the clock inside the universe – and we should not make it again. (pp.40-41)
This brings us back to our key question: Is the disappearance of time in the representation a deep insight into the nature of reality, or is it a misleading and unintended consequence of a method for approximately describing small parts of the universe? (p.42)
In its essentials, the Newtonian paradigm is constructed from the answers to two basic questions:
• What are the possible configurations of the system?
• What are the forces that the system is subject to in each configuration?
The possible configurations are also called the initial conditions because we specify them to get started. The rules by which the forces and their effects are described are called the laws of motion. These are represented by equations. (p.44)
We should be aware that this powerful method is based on some powerful assumptions. The first is that the configuration space is timeless. It’s assumed that some method can give the whole set of possible configurations ahead of time – that is, before we can watch the actual evolution of the system. The possible [emphasis added, ed.] configurations do not evolve, they simply are. A second assumption is that the forces, and hence the laws the system is subject to, are timeless. … The lesson here is as simple as it is terrifying. To the extent that the assumptions underlying the Newtonian paradigm are realized in nature, time is inessential and can be removed from the description of the world. (p.44)
But there is one important assumption that can be questioned, which is that you can extend the Newtonian method to the universe as a whole, by including everything in the box. But physics in a box starts by isolating a small subsystem of the universe. Can Laplace really get away with ignoring that step? Let’s go back to the game of catch in the park. (p.46)
Many laws of physics are time-reversible. One is Newtonian mechanics, another is general relativity, still another is quantum mechanics. The Standard Model of Particle Physics is almost time-reversible but not fully so. (There is one mostly inconsequential aspect of the weak nuclear interaction that does not reverse.) … These reversals are another argument for the unreality of time. If the direction of the laws of nature can be reversed, then there cannot, in principle, be any difference between the past and the future. (pp.52-53)
In his early work, Einstein also utilized a strategy called operationalism. According to this approach, the only meaningful way to define a quantity like time is to stipulate how to measure it. If you want to talk about time, you must describe what a clock is in your theory, and how the clock works. When you’re approaching science operationally, you ask not about what is real but what an observer could observe. … This enables you to ask whether different observers will agree of disagree about what they’re seeing. …The test of whether something is real – objectively true – is that all observers will agree on it. … What Einstein found was that there’s an ambiguity in any definition of distant events as simultaneous. (p.56)
For physics to make sense, observers have to agree on the order of causally related events to avoid confusion about the attribution of causes. But there’s no reason for observers to agree about the order of events that could not possibly affect each other. In Einstein’s theory of special relativity, they don’t agree. (p.57)
Besides the existence of a universal speed limit that all observers agree on, special relativity depends on one other hypothesis. This is the principle of relativity itself. It holds that speed, other than the speed of light, is a purely relative quantity – there’s no way to tell which observer is moving and which one is at rest. … Thus, there can be nothing objectively real about simultaneity, nothing real about “now”. … No meaning to “future” or “past” or “present”. (pp.57-58)
The number of times it ticked between the two events is something else all observers, regardless of their relative motion, can agree about. This is called the proper time. (p.59)
The block universe is the culmination of the movement begun by Galileo and Descartes to treat time as if it were another dimension of space. (p.59)
John Randoplh Lucas writes: “The block universe gives a deeply inadequate view of time. It fails to account for the passage of time, the pre-eminence of the present, the directedness of time and the difference between the future and the past.” (p64)
In general relativity, time can be measured at each point by a different clock, each running arbitrarily fast compared to the others, as long as surfaces of equal time are not causally related to each other. We call this freedom for time to be “many-fingered”, … (p.65)
Because of the relativity of simultaneity, different observers differ as to which events are simultaneous. There is no simple, objective, observer-independent way to describe how space is curved. (p.68)
Perhaps the most remarkable consequence of the equations of general relativity is that the geometry of spacetime is distorted by the passage of wave through it. (p.69)
…, Einstein was guided by Ernst Mach, who introduced a principle we call Mach’s principle. This says that only relative motion should matter, so that if we get dizzy when we spin, it must be because we are spinning with respect to the distant galaxies. The claim that the effect is one of purely relative motion implies that we would feel equally dizzy were we to stay still and the whole universe spin around us. (p.70)
For if time has a beginning, then that origin of time must be explicable in terms of something that is not time. (p.71)
By removing the need for a clock outside the system, general relativity goes some distance toward a relational theory of physics. But it still is based on the Newtonian paradigm, as it can be formulated in terms of timeless laws acting on a timeless configuration space. (p.72)
Thus there are two opposing forces acting on the universe. Gravity from all the matter causes contraction, while the cosmological constant accelerates expansion. (pp.72-73)
If laws are timeless, then what were they doing before there was a universe for them to govern? Clearly the answer is that there was no time before the universe, which means that the laws must be a deeper aspect of the world than time. (p.74)
As in the case of Newtonian physics, the clock must be outside the system, along with the observers and their measuring instruments. But although the evolution of the quantum state is deterministic, the implications for the precise configurations of the atoms are only probabilistic – because the connection between the quantum state and the configurations is itself probabilistic. (p.80)
By definition, nothing can be outside the universe, not even a clock. So how does the quantum state of the universe change with respect to a clock outside the universe? Since there is no such clock, the only answer is that it doesn’t change with respect to an outside clock. As a result, the quantum state of the universe, when viewed from a mythical standpoint outside the universe, appears frozen in time. (p.80)
If we assumed the existence of time, we would say the universe was boring when it was small. Barbour says it is enough to say that being boring and being small are highly correlated properties of moments in the heap. (p.86)
Barbour asserts that in the right quantum state, the property of being full of complexity and life correlates with a large volume. Thus many, and perhaps most, of the configurations in the heap with large volumes will have living being in them. (p.86)
There is a preferred direction in configuration space, which is away from the configurations of small volume and towards larger volumes. When time emerges, increasing volume correlates well with increasing time, so this explains why the universe appears to have an arrow of time. (p.87) [But what explains the reference, then ..!? ed.]
Einstein’s discontent comes down to a simple insight. A scientific theory, to be successful, must explain to us the observations we make of nature. Yet the most elementary observation we make is that nature is organized by time. If science must tell a story that encompasses and explains everything we observe in nature, shouldn’t that include our experience of the world as a flow of moments? (p.92)
The nine arguments fall into three classes:
Newtonian arguments (that is, arguments stemming from Newton’s physics or Newton’s paradigm for doing physics):
• The freezing of motion by graphing records of past observations
• The invention of timeless configuration space
• The Newtonian paradigm
• The argument for determinism
Einsteinian arguments, stemming from the theories of special and general relativity:
• The relativity of simultaneity
• The block-universe picture of space-time
• The beginning of time in the Big Bang
Cosmological arguments, stemming from extending physics to the universe as a whole:
• Quantum cosmology and the end of time
These nine arguments lead to a view of nature that denies the reality of the present moment and instead speaks of nature in terms of the block universe picture in which what is real is only the entire history of the world taken as one. (pp.93-94)
Without these fixed reference points [clocks etc.; ed.], we would not know how to connect predictions f the theory with records of experiments. (p.104)
This has a stunning consequence: If these symmetries are approximate, then so are the laws of conservation of energy, momentum, and angular momentum. These basic conservation laws depend on the assumption that space and time are symmetric under translations in time, translations in space, and rotations. (p.118)
So the unknown cosmological theory will have neither symmetries nor conservation laws. Some particle physicists, impressed by the success of the Standard Model, like to say that the more fundamental a theory is, the more symmetries it should have. This is precisely the wrong lesson to draw. (p.118)
I believe that time is needed for any theory that answers the Why these laws? question. If laws are to be explained, they must evolve. … We can understand this as a statement of Leibnitz’s principle of sufficient reason: We should be able to say why the laws of nature we have discovered, rather than others, are the laws. Peirce re-emphasizes this in the following two sentences: “Uniformities are precisely the sort of facts that need to be accounted for … Law is par excellence the thing that wants reason..” (p.119)
Roberto Mangabeira Unger put this ore elegantly. Either time is real or it is not. If time is real, then laws are timeless – but then the choice of laws is inexplicable, for reasons we have already discussed. If, on the other hand, time is truly real, then nothing, not even the laws, can last forever. (p121)
Although we don’t yet have the cosmological theory, we already know something about it, if the principles I’ve put forward are sound:
• It should contain what we already know about nature, but as approximations.
• It should be scientific; that is, it has to make testable predictions for doable experiments.
• It should solve the Why these laws? problem.
• It should solve the initial conditions problem.
• It will posit neither symmetries nor conservation laws.
• It should be causally and explanatorily closed. Nothing outside the universe should be required to explain anything inside the universe.
• It should satisfy the principle of sufficient reason, the principle of no unreprocicated action, and the principle of the identity of the undiscernerables.
• Its physical variables should describe evolving relationships between dynamic entities. There should be no fixed-background structures, including fixed laws of nature. Hence the laws of nature evolve, which implies that time is real. (pp.121-122)
If cosmological natural selection is right, we would expect that nature has taken advantage of the possibility of making kaons in the center of neutron stars to lower the critical mass. (p.127)
That there was a large landscape of possible string theories was evident from Strominger’s aforementioned 1986 paper, but the situation became a crisis impossible to ignore when, in 2003, evidence was discovered for the existence of an astronomical number of string theories with small positive values of the cosmological constant. The number was roughly estimated at 10500. … Then in 2005, … Taylor and colleagues were able to construct evidence for an infinite number of string theories with small negative cosmological constants. (p.133)
The amount of freedom is expressed by how much information you need about a system to be able to make predictions about its future. (p.149)
The first hidden-variables theory was presented by Prince Louis de Broglie in 1927 at an iconic gathering of quantum physicists called the Fifth Solvay Conference … De Broglie’s theory resolved the conundrum of wave and particle in a way that is simplicity itself. He posited that there is a real wave and a real particle. Both have material existence. … The particle follows the wave. In addition to the usual forces – electricity, magnetism, and gravity – the particle is pulled by a force called the quantum force. This force pulls the particle toward the wave crest; hence, on average, the particle is more likely to be found there, but the connection is probabilistic. Why? Because we don’t know where the particle started out. Since we are ignorant of the particle’s initial position, we cannot predict exactly where it will be. The hidden variable we’re ignorant of is the position of the particle. (pp.157-158)
In De Broglie’s theory, both the particle and the wave are beables. In particular, a particle always has a position, even if quantum theory cannot predict it precisely. (p.158)
A few years later, a young German mathematician named Grete Hermann pointed out that Von Neumann’s proof had a big hole in it. He had apparently committed the fallacy of assuming what he wanted to prove and had fooled himself and other by cloaking the assumption in a technical axiom. But her paper was ignored.(p.158)
This implies a universal, physical notion of simultaneity that includes distant events and, indeed, the whole universe. This can be called a preferred global time (“global” here meaning that the definition of time extends throughout the universe). (p.164)
Remarkably, though, these two theories are equivalent to each other, because you can – by a clever mathematical trick that isn’t necessary to go into here – trade the relativity of time for the relativity of size. So you can describe the history of the universe in two ways, in the language of general relativity or the language of shape dynamics. (p.170)
As noted, one quantity not allowed to change when you expand and shrink scales is the overall volume of the universe at each time. This makes the overall size of the universe and its expansion meaningful, and this can be taken for a universal physical clock. Time has been rediscovered. (p.171)
As theoretical physicists, we did contemplate increasing the number of dimensions in the building as we grew, but we couldn’t get the architects to go for it. (p.174)
Hence the spin foam gives a quantum version of the block-universe picture, in which space and time are unified in a single structure. (p.179)
There are also results in string theory suggesting that spacetime can emerge in a bounded region – at least when the cosmological constant takes on a negative value. These arise in the context of the duality between general relativity and the scale-invariant theory conjectured by Juan Maldacena … (p.180)
This depicts a quantum geometry in which Mary and ted are neighbors. It’s as if they had both just bought cell phones; the space separating them as dissolved. (p.181)
This is what Buckminster Fuller did when he invented the geodesic dome, and there was a short period when they dotted the landscape, until people remembered the advantages of square rooms. (p.184)
An old question is whether the presence of time violates the many-fingered-time symmetry of general relativity. (p.190)
… which reinforces …: Space may be an illusion, but time must be real. (p.192)
If time is truly real, then there should be features of the universe that are explicable only if we assume that time is fundamental. These features should appear mysterious and accidental on the contrary assumption – that time is emergent. (p.193)
Complexity is improbable. It requires explanation. (p.193)
We can see from this example tha entropy is inverse to information. (p.197)
Take apart a cat into its constituent atoms and mix those atoms randomly in with the air in the room. There are many more microstates in which the cat’s atoms are randomly mixed in the air then there are microstates where the cats is reassembled and sitting on the couch, licking its fur and purring. (p.198)
Nonetheless, as long as there is a finite number of cards in the deck, there is a time by which the shuffles, taking place at one per second, are likely to have produced a complete reordering. This is called the Poincaré recurrence time. If you watch a system over much shorter times, you will likely only see entropy go up. But watch the system for longer than the Poincaré recurrence time and you will likely see entropy go down as well. (p.199) [Thus, emergent order, information, without a Cause ..!?; ed.]
And why do all these different asymmetries in time point the same way – toward increasing disorder? This is sometimes called the problem of the arrow of time. There are actually several different arrows of time in our universe.
The universe is expanding and not contracting. We call this the cosmological arrow of time.
Small bits of the universe, left to themselves, tend to become more disordered in time (the spilt milk, the air equilibrating, and so on). This is called the thermodynamic arrow of time.
People, animals, and plants are born as infants, grow up, age, then die. This can be called the biological arrow of time.
We experience time flowing from the past into the future. We remember the past but not the future. This is the experimental arrow of time.
There is another – less apparent than the preceding arrows but nonetheless a major clue. Light moves from the past into the future. Hence, the light that reaches our eyes gives us a view of the world in the past, not the future. This is called the electromagnetic arrow of time.
Light waves are produced by the motion of electric charges. Wiggle a charge and light spreads out, always moving outward into the future, never into the past. This seems to apply to gravitational waves as well. So there is a gravitational-wave arrow of time.
Our universe apparently contains many black holes. A black hole is highly asymmetric in time. …Why are there only black holes and not white holes? And why did the universe not start off filled with black holes? There seems to be a black-hole arrow of time, … (pp.204-204)
We might just see a random mess. Or, for that matter, the light formed in the Big Bang might carry images of things that were never there, like images of a garden with elephants munching on giant asparagus. (pp.206-207)
But if we run the movie backward in time, we see a universe filled with images of things that have yet to happen. (p.207)
This point has been emphasized by Roger Penrose, and he has proposed a principle to explain it, which he calls the Weyl curvature hypothesis. The Weyl curvature is a mathematical quantity that is non-zero whenever there is gravitational radiation or black or white holes. Penrose’s principle is that at the initial singularity this quantity vanishes. … It’s a time-asymmetric condition, because it is certainly not true at late times in the universe. (p.207)
If the fundamental law is time-asymmetric, then so are most of its solutions. … The mystery of why we see only images from the past and not the future is solved. … A time-asymmetric universe would no longer be improbable, it would be necessary. (p.208)
Can we speak of the universe as being improbable? (p.209)
We’ll start with a simple question: Can the universe contain two identical moments of time? (p.213)
This is Leibnitz’s principle of the identity of the indiscernables, which I described … as a consequence of his principle of sufficient reason. This principle holds that there cannot be two objects in the universe that are indistinguishable but distinct. (p.214)
According to the principle of the indiscernables, our universe is one where every moment of time, and every place at every moment, is uniquely distinguishable from any other. … In such a universe, there is never a complete realization of the conditions needed to make sense of the Newtonian paradigm. (p.215)
The question on which the future depends is, Do we live in a Boltzmannian universe or a Leibnizian universe? (p.216)
This is an example of a general principle: Flows of energy through open systems tend to drive them to states of higher organization. (p.217)
Highly complex systems cannot be in equilibrium, because order is not random, so high entropy and high complexity cannot coexist. Describing a system as complex does not just mean that it has low entropy. .. A better characterization of complexity, … is what we call variety. … Such conditions arise in nature in systems far from equilibrium as a result or processes of self-organization.(p.219)
A ubiquitous feature of such self-organizing systems is that they are stabilized by feedback mechanisms. (p.219)
Patterns in space and time are formed when different feedback mechanisms compete to control a system. When a positive-feedback mechanism competes with a negative-feedback mechanism but they act on different scales, you may get patterns in space. (p.220)
The universe is not only not Boltzmannian, it is becoming less and less Boltzmannian as time goes on. (p.221)
Systems held together by gravity behave in this crazy way. Starts, solar systems, galaxies, and black holes are all anti-thermodynamic. They cool down when you put energy into them. This means that all these systems are unstable. The instabilities drive them away from uniformity and stimulate the formation of patterns in space and time. (p.224)
So if the universe is infinite and Boltzmannian, we exist, just as we are, and act, just as we are acting, an infinite number of times. (p.228)
The next simplest way to avoid an infinite dead future is if the cosmological constant is not actually a constant. (p.234)
The theoretical evidence that cosmological final singularities bounce due to quantum effects, leading to a re-expansion of the universe, is even stronger than in the case of black-hole singularities. (p.235)
But suppose there is a meta-law. Shouldn’t we want to know why this meta-law, rather than a different one, governs the evolution of laws in our universe? And if a meta-law may act on past laws to produce laws in the future, part of the explanation for what the laws are presently ill depend on what those past laws were, so we can’t avoid the Why these initial conditions? question. The meta-law hypothesis could lead to an infinite regression … The other possibility is that there is no meta-law. There would then be an element of randomness in the evolution of laws, the result again being that not everything is explainable and the principle of sufficient reason is flouted at the very foundations of science. (p.243)
Such utterances reveal the absurdity of the view that mathematics is prior to nature. Math in reality comes after nature. It has no generative power. Another way to say this is that in mathematics conclusions are forced by logical implications, whereas in nature events are generated by causal processes acting in time. This is not the same thing; logical implications can model aspects of causal processes, but they’re not identical to causal processes. Logic is not the mirror of causality. (p.246)
So one of the most important lessons that follow once we grasp the reality of time is that nature cannot be captured in any single logical or mathematical system. The universe simply is – or better yet, happens. (p.246)
All the progress of human civilization, from the invention of the first tools to our nascent quantum technologies, is the result of the disciplined application of the imagination. … We are superb hunters and gatherers and processors of information, but we are far more than that: We have a capacity for imagining situations that are not implied by the data we have. (p.252)
This is the grand bargain of human life: to thrive on the cusp of uncertainty. We thrive on the boundary between opportunity and danger and live with the knowledge that we can’t control everything or keep bad stuff from happening every now and then. (p.253)
You and I look at the woman in the red dress sitting at the next table. Do each of us experience the same sensation (of red, I mean)? (p.269)
The question is, Why do we experience the qualia of red when our eyes absorb photons of a certain wavelength? This is what the philosopher David Chalmers calls the hard question of consciousness. (p.269)
The problem of qualia, or consciousness, seems unanswerable by science because it’s an aspect of the world that is not encompassed when we describe all the physical interactions among particles. (p.269)