Beyond the “Mechanism” Metaphor in Physics

In previous posts, I discussed the use of the “mechanism” metaphor in science. I argued that this metaphor was useful historically in helping us to make progress in understanding cause-and-effect patterns in nature, but was limited or even deceptive in a number of important respects. In particular, the field of biology is characterized by evidence of spontaneity, adaptability, progress, and cooperative behavior among life forms that make the mechanism metaphor inadequate in characterizing and explaining life.

Physics is widely regarded as the pinnacle of the “hard sciences” and, as such, the field most suited to the mechanism metaphor. In fact, many physicists are so wedded to the idea of the universe as a mechanism, that they are inclined to speak as if the universe literally was a mechanism, that we humans are actually living inside a computer simulation. Why alien races would go through the trouble of creating simulated humans such as ourselves, with such dull, slow-moving lives, is never explained. But physicists are able to get away with these wild speculations because of their stupendous success in explaining and predicting the motion and actions of objects, from the smallest particles to the largest galaxies.

Fundamental to the success of physics is the idea that all objects are subject to laws that determine their behavior. Laws are what determine how the various parts of the universal mechanism move and interact. But when one starts asking questions about what precisely physical laws are and where they come from, one runs into questions and controversies that have never been successfully resolved.

Prior to the Big Bang theory, developed in the early twentieth century, the prevailing theory among physicists was that the universe existed eternally and had no beginning. When an accumulation of astronomical observations about the expansion of the universe led to the conclusion that the universe probably began from a single point that rapidly expanded outward, physicists gradually came to accept that the idea that the universe had a beginning, in a so-called “Big Bang.” However, this raised a problem: if laws ran the universe, and the universe had a beginning, then the laws must have preexisted the universe. In fact, the laws must have been eternal.

But what evidence is there for the notion that the laws of the universe are eternal? Does it really make sense to think of the law of gravity as existing before the universe existed, before gravity itself existed, before planets, stars, space, and time existed? Does it make sense to think of the law of conservation of mass existing before mass existed, or Mendel’s laws of genetics existing before genes existed? Where and how did they exist? If you take the logic of physics far enough, one is apt to conclude that the laws of physics are some kind of God(s), or that God is a mechanism.

Furthermore, what is the evidence for the notion that laws completely determine the motion of every particle in the universe, that the universe is deterministic? Observations and experiments under controlled conditions confirmed that the laws of Newtonian physics could indeed predict the motions of various objects. But did these observations and experiments prove that all objects everywhere behaved in completely predictable patterns?

Despite some fairly large holes in the ideas of eternal laws and determinism, both ideas have been popular among physicists and among many intellectuals. There have been dissenters, however.

The French philosopher Henri Bergson (1859-1941) argued that the universe was in fact a highly dynamic system with a large degree of freedom within it. According to Bergson, our ideas about eternal laws originated in human attempts to understand the reality of change by using fixed, static concepts. These concepts were useful tools — in fact, the tools had to be fixed and static in order to be useful. But the reality that these concepts pointed to was in fact flowing, all “things” were in flux, and we made a major mistake by equating our static concepts with reality and positing a world of eternal forms, whether that of Plato or the physicists. Actual reality, according to Bergson, was “unceasing creation, the uninterrupted up-surge of novelty.” (Henri Bergson, The Creative Mind, p. 7) Moreover, the flow of time was inherently continuous; we could try to measure time by chopping it into equal segments based on the ticking of a clock or by drawing a graph with units of time along one axis, but real time did not consist of segments any more than a flowing river consisted of segments. Time is a “vehicle of creation and choice” that refutes the idea of determinism. (p. 75)

Bergson did not dispute the experimental findings of physics, but argued that the laws of physics were insufficient to describe what the universe was really like. Physicists denied the reality of time and “unceasing creation,” according to Bergson, because scientists were searching for repeatable patterns, paying little or no attention to what was genuinely new:

[A]gainst this idea of the absolute originality and unforeseeability of forms our whole intellect rises in revolt. The essential function of our intellect, as the evolution of life has fashioned it, is to be a light for our conduct, to make ready for our action on things, to foresee, for a given situation, the events, favorable or unfavorable, which may follow thereupon. Intellect therefore instinctively selects in a given situation whatever is like something already known. . .  Science carries this faculty to the highest possible degree of exactitude and precision, but does not alter its essential character. Like ordinary knowledge, in dealing with things science is concerned only with the aspect of repetition. (Henri Bergson, Creative Evolution, p. 29)

Bergson acknowledged the existence of repetitive patterns in nature, but rather than seeing these patterns as reflecting eternal and wholly deterministic laws, Bergson proposed a different metaphor. Drawing upon the work of the French philosopher Felix Ravaisson, Bergson argued that nature develops “habits” of behavior in the same manner that human beings develop habits, from initial choices of behavior that over time become regular and subconscious: “Should we not then imagine nature, in this form, as an obscured consciousness and a dormant will? Habit thus gives us the living demonstration of this truth, that mechanism is not sufficient to itself: it is, so to speak, only the fossilized residue of a spiritual activity.” In Bergson’s view, spiritual activity was the ultimate foundation of reality, not the habits/mechanisms that resulted from it (The Creative Mind, pp. 197-98, 208).

Bergson’s views did not go over well with most scientists. In 1922, in Paris, Henri Bergson publicly debated Albert Einstein about the nature of time. (See Jimena Canales, The Physicist and the Philosopher: Einstein, Bergson, and the Debate that Changed Our Understanding of Time). Einstein’s theory of relativity posited that there was no absolute time that ticked at the same rate for every body in the universe. Time was linked to space in a single space-time continuum, the movement of bodies was entirely deterministic, and this movement could be predicted by calculating the space-time coordinates of these bodies. In Einstein’s view, there was no sharp distinction between past, present, and future — all events existed in a single block of space-time. This idea of a “block universe” is still predominant in physics today, though it is not without dissenters.

Most people have a “presentist” view of reality.

But physicists prefer the “block universe” view, in which all events are equally real.

Source: Time in Cosmology

 

In fact, when Einstein’s friend Michele Besso passed away in 1955, Einstein wrote a letter of condolence to Besso’s family in which he expressed his sympathies to the family but also declared that the separation between past, past, and future was an illusion anyway, so death did not mean anything. (The Physicist and the Philosopher, pp. 338-9)

It is widely believed that Bergson lost his 1922 debate with Einstein, in large part because Bergson did not fully understand Einstein’s theory of relativity. Nevertheless, while physicists everywhere eventually came to accept relativity, many rejected Einstein’s notion of a completely determinist universe which moved as predictably as a mechanism. The French physicist Louis de Broglie and the Japanese physicist Satosi Watanabe were proponents of Bergson and argued that the indeterminacy of subatomic particles supported Bergson’s view of the reality of freedom, the flow of time, and change. Einstein, on the other hand, never did accept the indeterminacy of quantum physics and insisted to his dying day that there must be “hidden” variables that would explain everything.  (The Physicist and the Philosopher, pp. 234-38)

 

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Moving forward to the present day, the debate over the reality of time has been rekindled by Lee Smolin, a theoretical physicist at the Perimeter Institute for Theoretical Physics. In Time Reborn, Smolin proposes that time is indeed real and that the neglect of this fact has hindered progress in physics and cosmology. Contrary to what you may have been taught in your science classes, Smolin argues that the laws of nature are not eternal and precise but emergent and approximate. Borrowing the theory of evolution from biology, Smolin argues that the laws of the universe evolve over time, that genuine novelty is real, and that the laws are not precise iron laws but approximate, granting a degree of freedom to what was formerly considered a rigidly deterministic universe.

One major problem with physics, Smolin argues, is that scientists tend to generalize or extrapolate based on conclusions drawn from laboratory experiments conducted under highly controlled conditions, with extraneous variables carefully excluded — Smolin calls this “physics in a box.” Now there is nothing inherently wrong with “physics in a box” — carefully controlled experiments that exclude extraneous variables are absolutely essential to progress in scientific knowledge. The problem is that one cannot take a law derived from such a controlled experiment and simply scale it up to apply to the entire universe; Smolin calls this the “cosmological fallacy.” As Smolin argues, it makes no sense to simply scale up the findings from these controlled experiments, because the universe contains everything, including the extraneous variables! Controlled experiments are too restricted and artificial to serve as an adequate basis for a theory that includes everything. Instead of generalizing from the bottom up based on isolated subsystems of the universe, physicists must construct theories of the whole universe, from the top down. (Time Reborn, pp. 38-39, 97)

Smolin is not the first scientist to argue that the laws of nature may have evolved over time. Smolin points to the eminent physicists Paul Dirac, John Archibald Wheeler, and Richard Feynman as previous proponents of the idea that the laws may have evolved. (Time Reborn, pp. xxv-xxvi) But all of these theorists were preceded by the American philosopher and scientist Charles Sanders Peirce (1839-1914), who argued that “the only possible way of accounting for the laws of nature and for uniformity in general is to suppose them results of evolution.” (Time Reborn, p. xxv) Dr. Smolin gives credit to Charles Sanders Peirce for originating this idea, and proposes two ways in which the laws of nature have evolved.

The first way is through a series of “Big Bangs,” in which each new universe selects different laws each time. Smolin argues that there must have been an endless succession of Big Bangs in the past which have led to our current universe with its particular set of laws. (p. 120) Furthermore, Smolin proposes that black holes create new, baby universes, each with its own laws — so the black holes in our universe are the parents of other universes, and our own universe is the child of a black hole in some other universe! (pp. 123-25) Unfortunately, it seems impossible to adequately prove this theory, unless there is some possible way of observing these other universes with their different laws.

Smolin also proposes that laws can arise at the quantum level based on what he calls the “principle of precedence.” Smolin makes an analogy to Anglo-Saxon law, in which the decisions of judges in the past serve as precedents for decisions made today and in the future, in an ever-growing body of “common law.” The idea is that everything in the universe has a tendency to develop habits; when a truly novel event occurs, and then occurs again, and again, it settles into a pattern of repetition; that settled pattern of repetition indicates the development of a new law of nature. The law did not previously exist eternally — it emerged out of habit. (Time Reborn, pp. 146-53) Furthermore, rather than being bound by deterministic laws, the universe remains genuinely open and free, able to build new forms on top of existing forms. Smolin argues, “In the time-bound picture I propose, the universe is a process for breeding novel phenomena and states of organization, which will forever renew itself as it evolves to states of ever higher complexity and organization. The observational record tells us unambiguously that the universe is getting more interesting as time goes on.” (p. 194)

And yet, despite his openness to the idea of genuine novelty in the evolution of the universe, even Smolin is unable to get away from the idea of mechanisms being ultimately responsible for everything. Smolin writes that the universe began with a particular set of initial conditions and then asks “What mechanism selected the actual initial conditions out of the infinite set of possibilities?” (pp. 97-98) He does not consider the possibility that in the beginning, perhaps there was no mechanism. Indeed, this is the problem with any cosmology that aims to provide a total explanation for existence; as one goes back in time searching for origins, one eventually reaches a first cause that has no prior cause, and thus no causal explanation. One either has to posit a creator-God, an eternal self-sufficient mechanism, or throw up one’s hands and accept that we are faced with an unsolvable mystery.

In fact, Smolin is not as radical as his inspiration, Charles Sanders Peirce. According to Peirce, the universe did not start out with a mechanism but rather began from a condition of maximum freedom and spontaneity, only gradually adopting certain “habits” which evolved into laws. Furthermore, even after the development of laws, the universe retained a great deal of chance and spontaneity. Laws specified certain regularities, but even within these regularities, a great deal of freedom still existed. For example, life forms may have been bound to the surface of the earth and subject to the regular rotation of the earth, the orbit of the earth around the sun, and the limitations of biology, but nonetheless life forms still retained considerable freedom.

Peirce, who believed in God, held that the universe was pervaded not by mechanism but mind, which was by definition characterized by freedom and spontaneity. As the mind/universe developed certain habits, these habits congealed into laws and solid matter. In Peirce’s view, “matter . . . [is] mere specialised and partially deadened mind.” (“The Law of Mind,” The Monist, vol. 11, no. 4, July 1892) This view is somewhat similar to the view of the physicist Werner Heisenberg, who noted that “Energy is in fact the substance from which all elementary particles, all atoms and therefore all things are made. . . .”

One contemporary philosopher, Philip Goff of Durham University, following Peirce and other thinkers, has argued that consciousness is not restricted to humans but in fact pervades the universe, from the smallest subatomic particles to the most intelligent human beings. This theory is known as panpsychism. (see Goff’s book Galileo’s Error: Foundations for a New Science of Consciousness) Goff does not argue that atoms, rocks, water, stars, etc. are like humans in their thought process, but that they have experiences, albeit very primitive and simple experiences compared to humans. The difference between the experiences of a human and the experiences of an electron is vast, but the difference still exists on a spectrum; there is no sharp dividing line that dictates that experience ends when one gets down to the level of insects, cells, viruses, molecules, atoms, or subatomic particles. In Dr. Goff’s words:

Human beings have a very rich and complex experience; horses less so; mice less so again. As we move to simpler and simpler forms of life, we find simpler and simpler forms of experience. Perhaps, at some point, the light switches off, and consciousness disappears. But it’s at least coherent to suppose that this continuum of consciousness fading while never quite turning off carries on into inorganic matter, with fundamental particles having almost unimaginably simple forms of experience to reflect their incredibly simple nature. That’s what panpsychists believe. . . .

The starting point of the panpsychist is that physical science doesn’t actually tell us what matter is. . . . Physics tells us absolutely nothing about what philosophers like to call the intrinsic nature of matter: what matter is, in and of itself. So it turns out that there is a huge hole in our scientific story. The proposal of the panpsychist is to put consciousness in that hole. Consciousness, for the panpsychist, is the intrinsic nature of matter. There’s just matter, on this view, nothing supernatural or spiritual. But matter can be described from two perspectives. Physical science describes matter “from the outside,” in terms of its behavior. But matter “from the inside”—i.e., in terms of its intrinsic nature—is constituted of forms of consciousness.

Unfortunately, there is, at present, no proof that the universe is pervaded by mind, nor is there solid evidence that the laws of physics have evolved. We do know that the science of physics is no longer as deterministic as it used to be. The behavior of subatomic particles is not fully predictable, despite the best efforts of physicists for nearly a century, and many physicists now acknowledge this. We also know that the concepts of laws and determinism often fail in the field of biology — there are very few actual laws in biology, and the idea that these laws preexisted life itself seems incoherent. No biologist will tell you that human beings in their present state are the inevitable product of determinist evolution and that if we started the planet Earth all over again, we would end up in 4.5 billion years with exactly the same types of life forms, including humans, that we have now. Nor can biologists predict the movement of life forms the same way that physicists can predict the movement of planets. Life forms do their own thing. Human beings retain their free will and moral responsibility. Still, the notion that the laws of physics are pre-existent and eternal appears to have no solid ground either; it is merely one of those assumptions that has become widely accepted because few have sought to challenge it or even ask for evidence.

Objectivity is Not Scientific

It is a common perception that objectivity is a virtue in the pursuit of knowledge, that we need to know things as they really are, independent of our mental conceptions and interpretations.  It is also a common perception that science is the form of knowledge that is the most objective, and that is why scientific knowledge makes the most progress.

Yet the principle of objectivity immediately runs into problems in the most famous scientific theory, Einstein’s theory of relativity.  According to relativity theory, there is no objective way to measure objects in space and time — these measures are always relative to observers depending on what velocity the objects and observers are travelling, and observers often end up with different measures for the same object as a result.  For example, objects travelling at a very high speed will appear to be shorter in length to outside observers that are parallel to the path of the object, a phenomenon known as length contraction.  In addition, time will move more slowly for an observer travelling at high speed than an observer travelling at a low speed.  This phenomenon is illustrated in the “twin paradox” — given a pair of twins, if one sets off in a high speed rocket, while the other stays on earth, the twin on the rocket will have aged more slowly than the twin on earth.  Finally, the sequence of two spatially-separated events, say Event A and Event B, will differ according to the position and velocity of the observer.  Some observers may see Event A occurring before Event B, others may see Event B occurring before Event A, and others will see the two events as simultaneous.  There is no objectively true sequence of events.

The theory of relativity does not say that everything is relative.  The speed of light, for example, is the same for all observers, whether they are moving at a fast speed toward a beam of light or away from a beam of light.  In fact, it was the absolute nature of light speed for all moving observers that led Einstein to conclude that time itself must be different for different observers.  In addition, for any two events that are causally-connected, the events must take place in the same sequence for all observers.  In other words, if Event A causes Event B, Event A must precede Event B for all observers.  So relativity theory sees some phenomena as different for different observers and others as the same for different observers.

Finally, the meaning of relativity in science is not that one person’s opinion is just as valid as anyone else’s.  Observers within the same frame of reference (say, multiple observers travelling together in the same vehicle) should agree on measurements of length and time for an outside object even if observers from other reference frames have different results.  If observers within the same vehicle don’t agree, then something is wrong — perhaps someone is misperceiving, or misinterpreting, or something else is wrong.

Nevertheless, if one accepts the theory of relativity, and this theory has been accepted by scientists for many decades now, one has to accept the fact that there is no objective measure of objects in space and time — it is entirely observer-dependent.  So why do many cling to the notion of objectivity as a principle of knowledge?

Historically, the goal of objectivity was proposed as a way to solve the problem of subjective error.  Individual subjects have imperfect perceptions and interpretations.  What they see and claim is fallible.  The principle of objectivity tries to overcome this problem by proposing that we need to evaluate objects as they are in themselves, in the absence of human mind.  The problem with this principle is that we can’t really step outside of our bodies and minds and evaluate an object.

So how do we overcome the problem of subjective error?  The solution is not to abandon mind, but to supplement it, by communicating with other minds, checking for individual error by seeing if others are getting different results, engaging in dialogue, and attempting to come to a consensus.  Observations and experiments are repeated many times by many different people before conclusions are established.  In this view, knowledge advances by using the combined power of thousands and thousands of minds, past and present.  It is the only way to ameliorate the problem of an incorrect relationship between subject and object and making that relationship better.

In the end, all knowledge, including scientific knowledge, is essentially and unalterably about the relationship between subjects and objects — you cannot find true knowledge by splitting objects from subjects any more than you can split H2O into its individual atoms of hydrogen and oxygen and expect to find water in the component parts.