Showing posts with label Paradigms. Show all posts
Showing posts with label Paradigms. Show all posts

Friday, May 22, 2009

Paradigm Shifts - II

One of the more fascinating aspects of this subject—world views, paradigms—is that we apparently know much more about the cosmos than we know about our own backyard. Studies of the big bang knowledgably discuss events said to have transpired one or two millionth of a second after the big bang began, but our very best theories of the solar system’s origins are very speculative at best. I will document this presently but want to draw the conclusion first. The closer we are to actual realities—and therefore our data are ample and our measurements good—the more obvious become the paradoxical features of reality and the more clearly we see that our explanations are groping, flailing, and often rather arbitrary. For this reason astronomers are much more realistic and tentative in discussing the solar system than they are theorizing about the universe. And apparently far more people spend far more time on the cosmos than on the messy solar system. But let’s look at that system.

Today’s dominant theory of the solar system’s formation presumes that it is the condensation of a cloud of dust and gases, a nebula. This cloud eventually collapsed into our sun when matter at its center aggregated initially by random motions. Under the force of the increasing gravity, the rest of the cloud flattened into a disk rotating in a counter-clockwise direction as perceived relative to the sun from the Earth. Within that disk clumps formed. They are called planetismals—for planetary seeds. Planetismals aggregated yet more material and became planets. By secondary processes, these bodies in turn, also rotating, caused moons to form around them. The planets in the aggregate account for about 1 percent of all the matter in the original cloud, the sun for 99 percent. This suggests that the sun itself should have the greatest angular momentum in the system in that it has the greatest mass. The inner planets are small, dense, and heavy; the outer are large and gaseous—and this distributional effect is due to sorting by density under the gravitational influence of the sun. All this makes sense, of course: one thinks of a blender, with the rod of the blender creating a little hole in the middle representing the pull of gravity.

Indeed the picture, and the theory, would be indisputable if only the solar system—and stellar clouds, for that matter—obliged us by behaving properly. For starters there is the fundamental problem, explained away by various stratagems, that vast clouds of dust just don’t clump up but, instead, have the tendency to spread. But never mind that. Assuming that the process starts somehow, proper behavior would be indicated if (1) the sun had nearly all of the angular momentum of the system, (2) if all of the planets rotated around their axes in the same direction as the sun, i.e., counter-clockwise, (3) if their axes were oriented in the same direction, i.e. parallel with the sun’s, and (4) if their moons also obligingly circled them in the same direction and with the same spin-direction as the planets themselves exhibit when circling the sun. The composition of planets and moons should also be in line with their location. Thus the moon should be as dense as the earth and the moons of Jupiter as gaseous as that planet.

The real facts are otherwise. The sun, with 99 percent of mass, has only 3 percent of the solar system’s angular momentum—Jupiter has 60 percent. Venus, Uranus, and Pluto rotate clockwise. The axis of the Earth is tilted at an angle to the sun’s. The axes of Uranus and Pluto point at the sun. Some of Jupiter’s moons circle it counter-clockwise, others clockwise. And the moon is of a much lighter density than the Earth’s so that its origin cannot be—and is not—attributed to condensation. We are thus faced with a sequence of questions: How did the sun lose its momentum, how did the rebellious planets acquire their contrary rotations, how did the axes of some planets get their tilt? Where does the moon originate and when did we get her? In addition to such questions we have yet other strange anomalies: the asteroid belt is one, the rings of Saturn another, and the comets (they come in two categories) yet a third. Pluto presents us with the interesting fact it has been demoted from planetary status in our lifetime. It has a rather eccentric orbit.

Notice the elegance of the original theory and the messy details of actual behavior. In all such cases science has a tendency to introduce ad hoc explanations which, while plausible in human experience (“Shit happens,” as we say), are difficult to reconcile and to embed neatly in a coherent and unified theory.

The nebular theory, which goes way back to Descartes (who imagined a gigantic whirlpool in a cosmic fluid), later developed a “catastrophic” competitor. Under this scenario, the sun encountered another sun wandering the cosmos. The intruder, interacting with the sun, ripped a huge tide of matter from the sun which, condensing out, formed the planets. This theory had the benefit of at least potentially explaining the sun’s low angular momentum—by hypothesizing that the visiting body gave up some of its angular energy to the ripped-out tide. The action itself—being, in a sense, wide-open to the imagination—could at least vaguely explain the strange rotations of Venus, Uranus, and Pluto. But the catastrophic theory lost momentum. It had its origins with Buffon in 1745, thus in the period leading up to the French Revolution. All things “revolutionary” were strongly resisted in the next century—hence the success of Darwin’s gradualistic theory of evolution based on Lyle’s gradualistic geology, which Lyle in part formed to counter Georg Cuvier’s catastrophic vision; Cuvier, of course, had studied actual geology and had reached his startling conclusions by looking. The realistic critique of the “tidal” theory is that such a violent encounter would more likely result in the dispersal rather than in the condensation of matter.

Despite the rejection of catastrophic origins, that theory still plays a major role in today’s consensus opinion in yet more ad hoc formulations. Thus the contrary rotations of three planets (or two if you don’t include Pluto) are explained by collisions and interactions between planetismals; but how these bodies got into erratic motion in the first place is not really developed. Similarly, the asteroid belt is explained either as the shatter of a planet or the inhibiting influence of Jupiter preventing aggregation. G.P. Kuiper (known for predicting the Kuiper Belt on the fringes of the solar system) speculated in 1951 that the sun’s planetary systems are the consequence of a failure. “It almost looks as though the solar system is a degenerate double star,” he wrote, “in which the second mass did not condense into a single star but was spread out—and formed the planets and comets.” Jupiter’s distance from the sun and the mass of the planets as a whole are about right (based on observation of binary systems) to support this hypothesis. But this notion also fails to explain the existing anomalies. Theories for the moon’s origin are based either on catastrophic interactions, e.g., the moon having been ripped from the relatively light outer mantle of the Earth by a passing body (a tidal theory in miniature), or on erratic wandering bodies, with the moon being captured by the Earth. Comets, the strange orbits of which do not fit the nebular theory—and there are short as well as long-period comets—are often the deus ex machina invoked to explain catastrophic events. To be sure, they don’t properly fit any elegant picture of the solar system’s orderly formation.

The closer we are to our subject the more variables appear to be present and therefore mathematical modeling of systems is more difficult. In cosmology, for instance, a few simple subatomic particles plus gravity, pressure, mass, and heat are the manageably few variables. Even so, the big bang theory failed to predict the formation of suns and galaxies until Alan Guth offered a rather arbitrary scenario in 1980. In its earliest stages, Guth said, the universe temporarily accelerated its expansion, a process known as “inflation.” In this process evidently gravity had to work in reverse (!!) There is no way to verify inflation, but it is accepted. Without this “kick” or “leap” of faith, the theory would have died an early death. What kept it alive—and the reason why Guth found support—was because the overall expansion of the universe, discerned from the red shift, had to be explained somehow. But the point here is that even a simple model with just a few variables, had and continues to have problems. How much more so the solar system—and never mind DNA.

The reason why mathematical models are so important is because they seem to bring coherence to what at first appear as irreducibly chaotic phenomena. Modeling imposes an order on chaos but usually at the cost of simplifying the inputs by leaving out much or averaging what seem to be minor influences. Models then produce predictions which can be tested by observation. The difficulties and limitations of modeling, however, are neatly illustrated by the cleverness of pre-Galilean modelers of the solar system. Their model accurately predicted the future position of planets although it was constructed on the assumption that the earth stood still and all else moved. It also became very complex as ever new solutions had to be devised to accommodate ever new observations that failed to fit properly. The Ptolemaic model was eventually replaced when better instruments emerged. Today’s big bang theory is accumulating ever more hypotheses and ever more work-arounds, like the Ptolemaic model did in the past. The big bang is under challenge from all sides. It requires Guth’s strange inflation; the cosmos displays large structures for the formation of which insufficient time has passed; one of these is the Great Wall, the first such discovered, others have been noted as well; a picture of it is here. In recent decades, furthermore, gravitational anomalies have been observed countered by positing undetectable dark matter and dark energy which constitute the overwhelming mass of the cosmos(!??). Indeed, doubters within science itself have identified twenty or more anomalies the theory fails to explain adequately—and plasma physics, which emerged in the mid-twentieth century in sophisticated form, offers alternative avenues of explanation. Cosmology is therefore gradually sliding into crisis.

Einstein’s theory of relativity is also eroding as discoveries in quantum physics have produced physical evidence for faster-than-light communications between subatomic particles—to name just one instance. Quantum physics is itself the earliest child of a physics largely developed in the changing—and indeed darkening—times of what seems a new era to me. It dissolves Einstein’s reality into energy, suggests that the predictabilities of physics are confined to macroscopic aggregates of energy, i.e., matter as we see it, and that beneath it is a boundless indeterminacy which may require an observer to become visible at all. The universe is thus a vast cloud of probability; observation causes probability waves to collapse; the observer becomes integral to the universe and, in a sense, creates reality.

Arguably if the observer really has a role in quantum physics, that observer should be explained as well. The positivistic explanations of intelligence seem inadequate to the purpose and may foreshadow changes in the area most resistant to change, the naturalistic theories of life.

Finally, in psychology, a hydra-headed cluster of genuinely scientific findings, both positive and negative, are weakening the positivist consensus that mind its an epiphenomenon. Interesting approaches are from the angle of the paranormal—including psychic powers in animals and hard research into reincarnation. Negative data show the persistent failure of naturalistic science in locating memory in the brain itself.

In sum, the paradigms they are a changing. Will the new theories, as they emerge and take hold, exhaustively describe the cosmos, life, and man? I doubt it.

The last word belongs to Heraclitus who claimed that there is a tendency in nature for all things to become their opposites. He labeled this enantiodromia, meaning “counter-running.” One might say that every such transformation produces a new vision of reality but never one that is complete. Around and round she goes, but where she stops nobody knows.

Wednesday, May 20, 2009

Paradigm Shifts: I

This interesting phrase originated with Thomas S. Kuhn in a book titled The Structure of Scientific Revolutions (1962) available here. I came across it in the Econ Division’s library at one of my alma matris, Midwest Research Institute, early during my time there. I had no idea lounging there and reading the book over a number of lunch hours that its publication was a landmark event: a genuine cultural approach to science had been born. The piously accepted view until Kuhn was that science changed incrementally as theories were falsified. He proposed shifts of mood more profound and basic in which a theoretical framework grown too overburdened by bad results and clever workarounds is finally thrown over, replaced by a competing view. This notion seemed natural to me because I’d grown up with ideas about culture gathered from my cyclic historians. Thus cultural views cycle radically when the benefits of a dominant world view have been exhausted. In the case of cultural forms, “inwardly” oriented cultures give way to those “outwardly” oriented. The shifts between eras are marked by “renaissances.” It took me most of my life to realize? suspect? that nineteenth century Romanticism was actually a renaissance-like period—but one of those that stand between an “outward” and an “inward” era: those tend to be less splendid than the reawakenings that follow the “dark ages” of inwardness.

Paradigm shifts in science have some of the same flavor and are themselves powerfully influenced by cultural tendencies, but scientists themselves, at least in our times, have tended not to notice that, which is not really surprising in that science is supposed to be concerned with the “real” rather than the slippery, fuzzy, ambiguous, and maddening aspects of the typically human. The great sweep of contemporary science, now effectively visible to an energetic surveyor in some detail, reveals what must be disconcerting to the scientific mind—namely that physical reality itself is at least as maddeningly murky as the human.

It seems to me that we’re likely to see several very major shifts in paradigm in the course of the current century. The century itself appears to be the first or second step into the dark woods of an inward age—with all the chaos and trauma of transition still largely ahead. Thus the shifts in science will reflect the flavor of the age to come. Transformations are signaled in all major sciences: In biology Darwinism will be revised; in physics Einstein’s theories will be honorably retired; in quantum physics the Copenhagen interpretation will be jettisoned; in cosmology the big bang will fizz out; and in psychology the Freudian consensus, which began to quaver almost as soon as formulated, will be entirely replaced. Brave words—but only to the historically challenged; to others almost self-evident.

Such predictions are rather easier to make at certain times in history. All systems decay slowly over time. Falsifications, which are supposed to cause science to react rapidly, do not actually have that consequence because institutionalized priesthoods resist the piecemeal overturn of systems; but falsifications take place steadily and cumulate—and this accumulation is observable. More dramatically, heretics appear quite early in the process. They do not succeed initially but serve to synthesize and dramatize the conflict. They lead small groups to the fault lines of modern theories and stand there pointing at the strange vapors that rise up from the ground. Heretics are derided, marginalized, and suffer a range of ignominies. Nevertheless they do their job.

Not surprisingly many of these phenomena are also closely linked—so that weaknesses in physics show up in astronomy, in geology, in biology, and, once in biology, also in psychology.


* * *

The current paradigm is progressive in flavor. Roughly 14 billion years ago the universe burst into being in a grand explosion from a peapod-sized but almost immeasurably concentrated quantity of matter. The explosion created space and time as the matter expanded at colossal speed, spread, and settled into clouds, suns, and galaxies. The expansion is still going on. Space and time are functions of matter. The universe is ruled by four forces: gravity, electromagnetism, the strong force (it holds the atomic nucleus together), and the weak force (it explains nuclear decay and hence radiation). We’ve managed to integrate all but gravity into models, but a “unified theory” that integrates gravity still eludes us. In addition to these forces and the motions they produce or inhibit, chance rules the universe. Life is a complex interaction of matter in its two forms of matter and energy (which are fundamentally equivalent). Once life emerges it evolves driven by a survival urge aided by changes brought on by chance, but since life appears to aim for greater complexity, matter may have a tropism toward complexity on the one hand and toward entropy on the other. Consciousness is a secondary phenomenon, a shadow of the underlying neuronal activity not important in itself (an epiphenomenon); in other words, consciously or not, we would still do the same things. The universe may continue to expand until it achieves energy death or, all depending on how much matter is present, it may begin contracting again and end again, as it began, in a singularity.

Under this paradigm we cannot explain: (1) how the big bang ignited, (2) how galaxies formed without the presence of immense quantities of dark matter and dark energy that we cannot find, (3) how life originated, (4) why it tenaciously clings to forms defined by genetics, and (5) what any of this means.

The dominant cosmological paradigm is justified by Einstein’s theory that gravity is the deformation of space-time by the mass of matter and by observations that light from very distant galaxies is shifted to the red end of the spectrum; this shift is interpreted to mean that every galaxy is moving farther away from every other. If we imagine this explosion in reverse, it appears as if the big bang took place 14 billion years in the past. Interestingly enough, the theory assumes that space itself expands rather than that the galaxies are flying apart in a preexistent space—because the theories of Einstein teach that mass itself somehow “creates” space and time. A few have offered alternative explanations for the red shift, but the big bang theory has become fiercely-defended orthodoxy; alternatives need not apply.

Just to make a distinction, I note here that in the Newtonian cosmology both space and time had absolute meanings and were thus not functions of matter. In that time only one of the four “forces,” gravity, was even recognized to exist. Newton didn’t know what it was and said “I do not frame hypotheses.” His cosmology was strictly descriptive.

[To be continued.]