|Unification of Science and Spirit -- Copyright Ben Goertzel © 1996|
He who tries to understand quantum theory vanishes into a black hole, never to be seen again.
-- Richard Feynman
The Perennial Philosophy has been fairly constant throughout recorded history. It transcends cultures and continents. Different traditions cast it in different forms, adorn it with different rituals and concepts; but the core is the same. This is because the spiritual experiences on which the Perennial Philosophy is based are essentially culture-independent. The experience of higher levels of being, the experience of the Absolute -- this is substantially the same, whether one is a Stone Age cave artist, a Vedic poet, an ancient Chinese farmer, an Amazonian shaman, or a moon-worshipping New York taxi driver. The common core among different mystic traditions is precisely common experiences on the higher levels of being. The differences result from different ways of bringing these experiences down to the lower levels -- of expressing them in terms of physical, emotional and mental forms.
It is possible that different species, or intelligent computers, might have a fundamentally different way of experiencing spiritual reality. For humans, however, there seems to be a very strong common core. Essential aspects of spirituality have remained constant over human history.
Science, on the other hand, has not been at all constant over its much shorter lifespan. The scientific method has not changed much, but the basic world-view implicit in the body of scientific knowledge has undergone drastic alterations. In particular, as we approach the twenty-first century, the view of the world implicit in nineteenth-century science is now completely gone. The world as portrayed by late-twentieth-century science is a totally different place.
While different wisdom traditions are based on the same inner experiences, different phases of science are based on different outer experiences, different kinds of experiments. Science progresses in a way that spirituality does not, perhaps because, unlike spirituality, it is fundamentally bound to the temporal world.
In particular, the world portrayed by nineteenth-century science had almost nothing in common with the lessons of spiritual experience. It was a world with absolute reality, evolving according to rigid, deterministic laws, and leaving no room for free will, creativity, spirit or true spontaneity. It was, in short, a mechanical world. The universe was viewed as a kind of giant automated factory. It was a "clockwork universe."
The world portrayed by the science of today, on the other hand, is much more harmonious with spiritual ideas. It is a world whose reality is tentative and, in several senses, subjective. It is a world full of randomness and chaos. It is a world dominated by intricate emergent forms -- forms which, in practice, cannot be predicted from their component parts or generating processes. It is a world in which each mind creates its own reality -- and in which space and time themselves are viewed as emerging from a more fundamental realm of interacting, intertransforming processes.
One cannot say that science has arrived at a spiritual view of the world. This would be going too far. But what one can say is that science has arrived at a world-view that is strikingly consistent with the insights achieved through spiritual experience. It is this new consistency that has opened the door for a unified vision of the mind, a vision bridging both science and spirituality. The clockwork universe of nineteenth-century science is gone, replaced with a more flexible, open, dynamic, living world.
It is, finally, in this context that the concept of a digital universe must be interpreted. The digital universe is not a mechanistic universe in the sense of Isaac Newton. It is a massively parallel, self-organizing quantum computer, full of randomness, emergent chaos and emergent pattern, as well as routinized, mechanistic procedures. Computational modeling does not reduce everything to clockwork: rather, interpreted in the light of turn-of-the-millenium "postmodern" science, it reduces everything to self-organization and self-creation.
Like any other world-view, the "clockwork universe" did not emerge all at once. It came about gradually, piece by piece, due to the efforts of thousands of different researchers, in coordination with general intellectual movements and cultural changes. However, there is one event which is traditionally distinguished as marking the beginning of the clockwork universe era: the publication, in 1687, of Isaac Newton's masterwork Philosophiae Naturalis Principia Mathematica.
Newton's universe made perfect sense. The world is made of objects, moving through Absolute Time and moving in Absolute Space. And the motions of the objects are determined by a few simple rules. An object moving in a straight line will continue to move in a straight line, unless its motion is interrupted. Every action has an equal and opposite reaction. Finally, the amount of force experienced by an object is given by its mass multiplied by its acceleration. Previous to Newton, force hadbeen thought to have to do with velocity. Newton saw that, instead, it had to do with acceleration. This and other acute physical/mathematical insights made Newton's physics a scientific theory of awesome grace and power, the likes of which had never been seen before, and have not been seen since.
Newton himself did not attempt to give a complete theory of the universe. He knew there were phenomena, such as electricity, that his theory did not touch. But the power and elegance of his theory inspired many others. Faraday and Maxwell brought electromagnetism into the fold. Laplace and many others made exhaustive investigations into astronomy. By the end of the nineteenth century, the theory of mechanics and electromagnetism had blossomed into a comprehensive explanation of all physical phenomena. Or so it was thought. The dean of a prestigious physics school cautioned students to think twice about going into physics -- because all the interesting questions had been answered already.
Even today, it is not hard to see why the nineteenth-century physicists were so smug. Classical physics explains an astounding variety of real-world phenomena -- the flow of fluid through the heart, the trajectory of a basketball, the motions of the planets, the behavior of light bulbs, eyes, ears and automobile engines.... All these phenomena may be understood using the metaphor of the "clockwork universe" -- the universe as a series of mechanical objects, connected to each other in various ways, and with an overall behavior easily predictable from the properties of the component parts.
But, impressive as nineteenth-century Newton-style physics is, we now know that it is wrong. It is wrong in detail, for two different reasons. And, for a third reason, it is also wrong in spirit. Einstein's relativity theory tells us that classical physics is incorrect for objects which are very dense or which move very fast. Quantum theory tells us that classical physics is incorrect for objects which are very small -- as well for as some not-so-small objects, such as superconductors, and, conceivably, human brains. And, finally, chaos theory and complexity science show us that nineteenth-century scientists were totally wrong in their understanding of predictability and pattern in the universe.
These shortcomings of Newtonian physics turn out to have profound philosophical implications, which can be easily understood in terms of the hierarchical model of the universe. Chaos theory, I will show in a later chapter, is the key to understanding the mind. It is the bridge between the realm of the body and the realm of intuition -- between the lower and higher realms. On the other hand, quantum theory indicates a new level of being beneath what was traditionally thought of as the bottom level, the physical world. By indicating a new, subterranean level of being that in fact resembles the higher levels of being, quantum physics out-does the mystics at their own game. It turns the hierarchy of being into a circle of being.
Quantum physics, more than any other scientific theory, stretches our notion of reality. This is why the early quantum physicists -- Planck, Einstein, Rutherford, Bohr, and others -- were so shocked by their discoveries. They found it difficult to accept that the world of microscopic particles is nothing like the everyday world you and I know. The particles that make us up live in a strange place called quantum reality.
I will not attempt to give a complete account of quantum physics here. There are several excellent trade books covering this ground, including Fritjof Capra's The Tao of Physics, Gary Zukav's The Dancing Wu Li Masters, Fred Alan Wolf's Taking the Quantum Leap, and Nick Herbert's Quantum Reality. Here I will take a quick tour through some of the more bizarre features of quantum reality, and then linger a while on issues of quantum measurement and quantum gravity, which are particularly relevant to the relation between quantum reality and the other levels in the hierarchy of being.
The word "quantum" means "a discrete amount." The beginning of quantum theory was the observation that the properties of atoms do not, like the properties of things like baseballs, people or stars, vary smoothly and continuously. Instead, the motion, spin and energy of different atoms may vary, but only through a discrete range of values. The discrete, "chunklike" nature of atoms and particles may seem a fairly harmless, unexciting fact. Who cares if quantities vary continuously or discretely? In fact, however, the quantal nature of the microscopic world leads to a never-ending series of bizarre consequences.
The phenomenon of discreteness or "quantization" was first described by Max Planck in 1900, in a paper on the distribution of radiation emanating from a hot body ("black body radiation"). The only way to explain the way the radiation was distributed, Planck observed, was to assume the radiation was emitted from the body in discrete bundles, or "quanta." Then, in 1905, Einstein introduced the quantization of light. In a bold theoretical mave that went against prevailing wave theories of light, he predicted the existence of particles called "photons." In this way he explained the photoelectric effect, a phenomenon in which light energy displaces electrons from the surface of metals. Niels Bohr, in 1913, used these photons to give a new theory of the structure of the atom.
Bohr's theory of the atom epitomized the "old quantum mechanics," which was much like classical physics, but with discrete physical quantities. In the mid-1920's and the 1930's, Heisenberg, Schrodinger, Dirac and Pauli took the next natural step, and created the "new quantum mechanics." The new quantum mechanics was no longer a modification of classical ideas, but rather a fundamentally different way of looking at the universe. Philosophically, the approach of the pioneers of the 20's and 30's was overwhelmingly pragmatic. Those who, like Einstein, were hung up on common sense, failed to make significant progress. For common sense is, by definition, based on experience with ordinary reality. And the task at hand was,precisely, the exploration of a new reality.
The new quantum physics was astoundingly successful, explaining such diverse phenomena as chemical bonding, atomic spectra, radioactivity and the structure of atoms. Combined with Einstein's relativity theory, it provided a framework for later developments explaining yet further phenomena: nuclear reactions, antimatter, the creation and annihilation of elementary particles. Technologically, quantum physics has played a decisive role in many inventions, including superconductors, semiconductors, computer chips, electron microscopes, lasers, transistors, brain scanning devices and, of course, nuclear weapons.
Quantum physics, as developed over the course of the twentieth century, is the most dramatic success story in the history of science. But yet, there is something troubling to the scientific mind about this tremendous conceptual edifice. The problem is, quite simply, that quantum reality makes no sense. Many of the quantum pioneers believed that their pragmatic approach was only a stopgap, that eventually, once enough progress had been made, the sense of it all would become apparent. But, sixty years later, this has not occurred. The quantum world seems even more bizarre than it did back then.
In quantum reality, the observer affects the observed. Looking at a particle -- say an electron (a particle of charge), or a photon (a particle of light) -- changes its state. Because of this, objects in quantum reality are not completely knowable. It is impossible to completely determine the state of a particle by any experiment. By observing the position of a particle, one alters its momentum, so its original momentum must remain unknown. By observing its momentum, one alters its position, so its original position must remain unknown.
This kind of behavior is unknown in everyday reality. We can measure the height, weight, breadth, and temperature of any ordinary object, at any given time, with no fundamental difficulties. But in quantum reality different qualities of an object interfere with each other, leading one to ask whether the qualities themselves actually have any meaning. If the position and momentum of an electron cannot both be measured at the same time, then what sense does it make to say that they both exist at the same time? In physics, one does not posit the existence of unmeasurable things. The answer seems to be that, at any given time, each of them only sort of half-exists. Then, once the measurement is done, one of them is chosen to exist and the other is chosen not to exist. The act of measurement, in some obscure way, determines reality.
Originally it was thought that this kind of indeterminacy was only significant in the microscopic realm -- that, although we might not be able to attain truly complete knowledge of a macroscopic system, we could get as close as any practical purpose could conceivably require. However, recent experiments with superconductivity have put an end to this dubious "loophole" method of dealing with quantum reality. Two British physicists named Spiller and Clark have constructed a device called a SQUID (superconducting quantum interference device), around the size of a thumbnail, the magnetic field of which displays classic Heisenberg indeterminacy. No matter how one tries, one cannotsimultaneously determine the intensity and the flux of its magnetic field. Several theorists in recent years have proposed that the human brain, like a SQUID, may also be a macroscopic quantum object.
Quantum physics synergizes well with Einstein's relativity theory. Putting the two together, one gets a theory called quantum electrodynamics, which is even more powerful than quantum theory, and even more bizarre.
Einstein's special theory of relativity is a theory of the motion of fairly large objects in situations where gravitational force is not important. It has some very strange implications -- for instance, according to special relativity, each point in space has its own individual measure of length and time. Suppose one takes two identical, incredibly accurate clocks, and sets them both to twelve noon. Then suppose one flies the first clock around the world on a Concorde jet, and leaves the second one in place. Special relativity says that when one returns, the first clock will be running a little behind the other one. Nothing has gone wrong with the operation of either clock. Time simply runs slower for moving objects.
This experiment has been done several times, with highly accurate cesium clocks. The result is always exactly as predicted by special relativity. The available data leaves little doubt that, if one were to set off in a spaceship traveling at nine tenths the speed of light, after a few hours of flying one would return in the distant future.
And similarly, just as moving clocks run slower, moving objects become heavier, and longer. This is not because their material is in some way "stretched" -- it is just a consequence of the fundamental nature of length and mass. Concepts like length, mass and time can only be measured relative to some particular point in space. This insight was the beginning of the modern revolution in physics. Each point in space must be envisioned to carry around its own "reference frame," its own scheme for measuring masses, lengths and times.
All the counterintuitive predictions of special relativity can be explained from one simple postulate. This is the hypothesis of a "cosmic speed limit" -- a speed limit which bound the possible speeds of all objects in the universe. From this assumption all of special relativity logically follows, by elementary algebra. It is an empirical fact that this cosmic speed limit is the speed of light, 186,000 miles per second. Nothing can go faster than this. Ever. Or so it appears, based on all the data the human race has been able to collect.
Of course, as with quantum indeterminacy, these strange relativistic effects are fairly insignificant for the motion of everyday objects. For instance, it is true that the clock in your car will run slower than the clock in your house, due to special relativity. But the amount of the difference is so small that the clocks in question are not accurate enough to register it.
Finally, what made special relativity famous was one simple equation, consisting of five marks: E = mc2. This is one case where an equation is better known than the idea underlying it. The E stands for energy, the m stands for mass, and the c is the speed of light, the cosmic speed limit. What this unforgettable equation says is that energy and mass are two different views of the same thing. This is the philosophical secret of the atom bomb: a nuclear explosion changes matter into energy, in a most dramatic way. Mass being static, and energy dynamic, the equation is a wonderful illustration of the interchangeability of being and doing.
As an aside, it is amusing to observe that, in relativistic physics, one generally measures mass and energy in relativistic units. In these units, c=1, so that Einstein's formula becomes merely E = m. I'm not sure why, but somehow this lacks the zing of the original version. The " c2" lends an attractive bit of mathematical spice to the formula. "E = m" looks too simplistic, too philosophical, not scientific enough! I often wonder what would have happened if Einstein had used relativistic units in his original paper -- perhaps the mass-energy equivalence formula would be nowhere near as well known as it is today!
Special relativity in itself is not accurate for extremely small particles, such as electrons or photons. Here quantum effects become significant, and one needs the combination of relativity and quantum theory, which is called relativistic quantum mechanics or "quantum electrodynamics," QED. Relativistic quantum mechanics is a very good theory of small particles whose energies are not too large. But if the energy of a particle is large, then even though the explicit mass of the particle is small, by E = mc2 we must consider gravitational effects, and General Relativity comes into the picture.
Special relativity and quantum theory mesh nicely together, in terms of predicting empirical data, but they create even more conceptual conundrums together than they do separately. For instance, according to Einstein's special relativity theory, nothing can travel faster than the speed of light -- not even information. But in quantum reality, looking at a particle over here can give one information about the state of a particle over there -- instantaneously, without any signal passing between the two. This is called "nonlocal correlation."
The concept of "nonlocal correlation" was first discovered by Einstein. Due to its bizarreness, he considered it a disproof of quantum physics, and published a paper (together with Podolsky and Rosen) saying so. In the end, though, the experimentalists proved that nonlocal correlation does exist. Rather than disproving quantum physics, as he had hoped to do, Einstein had just pointed out another one of the peculiar, counterintuitive properties of quantum reality.
Nonlocal correlation is well illustrated by the Aspect experiment, in which two coupled electrons are shot in opposite directions into empty space. Basic quantum physics says that each one spins either up or down, and if one spins up the othermust spin down. But it also says that, when the two electrons split up, each one has exactly a 50% chance of being the one that spins down. So what happens when the two electrons are far apart, and you measure one? The one which you measure attains a definite spin -- and so, consequently, does the other one. If the one you measure spins up, then the other one must spin down. An act of measurement has caused a reduction from uncertainty to certainty, instantaneously, at a distant location.
Now, think about doing the Aspect experiment with hundreds of electrons, one after the other. Suppose that, at location A, one obtains results of the form
Up Down Up Down Down Up Up ...
Then, at location B, one is guaranteed to obtain results of the form
Down Up Down Up Up Down Down ...
No information passed between A and B. But nonetheless, the sequence obtained at A is an exact mirror image of the sequence obtained at B. There is a correlation, but no information is transmitted.
This sort of experiment was, in essence, proposed by Einstein, Podolsky and Rosen (EPR) in their original 1935 paper. Such experiments were not actually done until the early 1980's, but nonetheless the phenomenon is called the EPR effect. Taken to its ultimate conclusion, the EPR effect implies that the entire universe is bound together: when any entity is measured, this in a sense affects every entity with which it has ever interacted.
Mathematically, this sort of phenomenon is described by Bell's Theorem. The Aspect experiment with spinning electrons is just an easy-to-visualize example. Bell's Theorem implies that the same sort of thing happens with complex systems that interact then separate. When one system is observed and hence changed, the other system is automatically, instantaneously changed as well -- no matter what the distance between them.
Stated a little differently, Bell's Theorem is about synchronicity. It does not state that patterns in one part of the universe will cause similar patterns to emerge in other parts of the universe. But it does state that emergent patterns will spontaneously form, spanning distant systems which have been "physically unrelated" for a long time.
The word "synchronicity" was introduced in the 1940's, in Carl Jung's book Synchronicity: An Acausal Connecting Principle. But only in recent years has it entered the popular vocabulary. In fact, a couple years back, David Peat and Allan Combs both simultaneously published popular science books entitled Synchronicity -- quite an instance of synchronicity! And in the early 80's the rock group "The Police" recorded an album called Synchronicity, with two hit songs entitled "Synchronicity" and "Synchronicity 2":
It's the one breath, it's the one flow -- synchronicity ...
It's a window, it's a window --
A connecting principle ...
In his little book Synchronicity (really just a long essay), Jung suggested that coincidence is not always the result of chance; that there is an additional force in the universe which causes "appropriate", "meaningful" things to happen at certain junctures. This is not, strictly speaking, a psychological hypothesis. To many it seems more metaphysical than scientific. But, taking into account Bell's Inequality and the quantum theory of measurement, one may see it in a rather different light.
According to accepted principles of quantum physics, looking at the world will in general cause certain emergent patterns -- certain coincidences -- to form. This scientifically validates Jung's basic intuition, in the abstract. I must admit that have trouble believing some of the examples which Jung gives in Synchronicity. I have a sneaking suspicion that virtually all of the coincidences that occur in everyday life are genuine chance phenomena. But, in terms of quantum physics, the scientific possibility is there for some coincidences to be more than that.
And EPR is just the beginning. In relativistic quantum theory, particles can be brought into existence by other particles, or can disappear entirely, annihilated by other particles. This does not happen in the macroscopic world. A baseball never collides with an anti-baseball and disappears; or, say, collides with a basketball and in the process produces a frisbee. In quantum reality, particles have the power to act on each other in very fundamental ways. Each particle is, in effect, a combination and relationship of other particles. Nothing exists in isolation. Everything is at bottom interdependent.
And things get stranger yet. Recent research shows that, in quantum reality, the simple idea of a linear time axis is no longer sufficient. To appreciate this, consider an experiment proposed by the German physicist Rossler. This experiment relies on the relativity of time, first identified by Einstein. Time relativity implies that two events which appear to be simultaneous to me, may not appear to be simultaneous to you. There is no universal way of determining whether two events happened at the same time: it all depends on where the observer is, and how the observer is moving. Observers in different places, or moving with different speeds, may well have different judgements of simultaneity.
Take two particles -- say, electrons -- and shoot them away from each other, in different directions. Then, measure the electrons with two different measuring devices, in two different places. According to special relativity, simultaneity is not objective, so, suppose Device 1 is moving with respect to Device 2, and Event A appears to Device 1 to occur before Event B. Thenit is nonetheless possible that to Device 2, Event B should appear to occur before Event A.
Next, suppose that Device 1 measures electron A, while Device 2 measures electron B. One may set the devices up so that, from the perspective of device 1, electron A is measured first, while from the perspective of Device 2, electron B is measured first. In the reference frame of each of the measuring devices, one has precisely the Aspect experiment. But one also has a problem. The notion of a measured state must be redefined so that it becomes observer-dependent. One cannot say in any "objective" way whether a given probabilistic superposition of states has collapsed or not; one can only say whether or not it has collapsed within some particular point of view.
This is a thought-experiment; it has not yet been performed. But no one has any serious doubts as to what the outcome would be. Either all of modern physics is incorrect or else, as the thought-experiment suggests, there is no observer-independent way of telling definite reality from indefinite, quantum-suspended reality.
So, suppose the outcome of the thought-experiment is as expected. An immediate conclusion is that the notion of a single time axis is inadequate for describing physical reality. They conclude that each observer must be considered to have its own "personal" time axis, along which probabilistic superpositions gradually collapse into greater definiteness. The single time axis of Newtonian, relativistic and quantum physics is a fiction -- an exceeding useful one, but a fiction nonetheless.
The list of bizarre quantum phenomena could go on on, but it is perhaps best to stop here, and take stock of some of the deeper implications of quantum theory.
Clearly, in many respects, quantum reality resembles spiritual reality. There are many similarities between quantum reality and the higher levels of the Vedantic hierarchy, e.g. anandamaya, the Overmind, the Realm of Bliss. For in anandamaya, everything is interdependent, everything is defined in terms of everything else. In anandamaya, the linear order of time is violated. In anandamaya, implicitly, observation is not an impartial act, but inevitably affects the observed -- because observer and observed are just formations emerging from a deeper realm of process dynamics.
Despite these parallels, however, one cannot reasonably conclude that quantum reality is anandamaya. Quantum physics involves specific equations that cannot be assumed to govern the higher levels of being. The higher levels of being are not governed by equations with specific numbers in them.
One reasonable view is that quantum physics shows us how annamaya -- the physical world -- emerges from anandamaya. It shows us that the solid, apparent world emerges from the world of fluctuation, atemporality, and interdependence. Many physicists have tried to minimize the surreal nature of quantum reality by pointing out that it only applies to the world of the very small, and to certain bizarre macroscopic objects likeSQUIDs. But this places them in the troublesome position of arguing that our apparently solid and definite reality is made of components that live in a nebulous, surreal reality. How real is a world that is made of unreality? This question, long posed by wisdom traditions, is now being posed by science.
An equally reasonable position, however, is that quantum physics represents an entirely new level of reality -- an addition to the Vedantic hierarchy, based on knowledge not available to the ancient Indians. After all, quantum reality has very little in common with the everyday physical reality that the Hindus called annamaya. Quantum reality is a new realm of being, not quite the same as any of the others. In a psychological or sociological sense, it emerges from annamaya: it is revealed by the behavior of macroscopic experimental apparatus, which exist firmly within annamaya. And in the physical sense, annamaya emerges from it.
Tongue halfway in cheek, one might call this new level of being quantum-maya. One might protest that quantum-maya is too different from the other levels in the hierarchy -- it is not an experience, not a state of consciousness. But, fundamentally, annamaya is not a state of consciousness either; like quantum-maya it is known to consciousness only through the mediation of the higher levels of being.
Supposing we admit quantum reality, Quanta, quantum-maya, as a new level of being. Then what happens is an amazing thing. The purely hierarchical structure of the Vedantic hierarchy is ruined. Instead, we have reached a level low enough that it is also high. We have the lowest level, Quanta or quantum-maya, coming very close to the second-highest level, anandamaya. The hierarchy becomes a circle, with atman at the top, anandamaya and quantum-maya next to it, and the others bridging the Realm of Bliss and the Quantum Realm in a continuous arc. One arrives at the Hierarchical Map of the Universe given above.
The Role of the Observer in Quantum Measurement
I have said that, in quantum physics, the observer affects the observed. This concept deserves a little more scrutiny. It is a concept that will emerge again in later chapters, when we discuss the mind and its various properties.
In Newtonian physics, the observer is separate from the observed. The observer is like someone watching a baseball game on television: he sees the events going on, but cannot influence them. In quantum physics, on the other hand, the observer and the observed are intertwined. The observer is more like a very loud spectator sitting in the front row at a baseball game. He can affect the game by his actions. He can throw things at the players. He can cheer, or boo. Even if he remains silent, this affects the players, because they notice the crowd's relative indifference. By merely being there, gathering information for himself about the game, he is inevitably changing the course of the game. He will never know exactly what would have happened in the game if he had not been there.
The puzzle of quantum measurement has drawn the attentionof a great number of physicists, beginning with the foundation of quantum physics and continuing to the present day. There are a number of different theories, and there is no consensus. The majority of physicists tend not to worry about the conceptual puzzles associated with quantum theory, perhaps believing, with Richard Feynman, that "He who tries to understand quantum theory vanishes into a black hole, never to be seen again."
The standard "Copenhagen interpretation," which seems to be held by a majority of physicists, at least on an implicit level, is the simplest and least interesting of all the possibilities. It states that, when a measurement is made, a quantum system suddenly collapses from a probabilistic superposition of states into a definite state. Measurement magically makes things definite.
To take Schrodinger's famous example, suppose we have a cat in a box with a gun, connected to a lump of radioactive material. The gun will go off and kill the cat whenever the radioactive material has decayed a certain amount. Suppose we open the box after a certain period of time. It is uncertain whether the the radioactive material has decayed enough yet. According to quantum theory, this is a matter of chance: there is no way to predict exactly how the decay is going to occur. So we don't know whether the cat is alive or dead, until we open the box. Once we open it, we can see very clearly whether it's alive or dead, however. According to the Cophenhagen interpretation, until someone looks, the cat is neither alive nor dead, it's in a kind of combination of states. But once someone looks, the cat becomes suddenly one or the other. Looking, measuring, makes things definite.
Of course, the question begged here is: What is measurement? How do we know when the cat has been measured. There is the so-called "paradox of Wigner's friend," which is: What if the person opening the box is himself in a bigger box. Does the cat's state of being become definite when the experimenter opens the box, or when the meta-experimenter opens the bigger box containing the first experimenter?
The paradox of Wigner's friend is generally circumvented by defining an act of measurement as "registration on some macroscopic measuring device." According to this view, things become definite when they are registered on something big, like a person, or a piece of paper. The idea is that big things are ruled by classical physics, and can have definite states. But of course, this is a monumuental cop-out, because big things, macroscopic devices, are really quantum systems too. Quantum physics is needed to explain the behavior of many large systems, such as the human body and brain.
Wigner himself proposed to define measurement in terms of consciousness. Not just any measuring device will do, he proclaimed -- in order for a quantum phenomenon to become definite, it has to enter into some conscious mind. The weak point here, of course, is that consciousness itself is not a well-defined entity, not from the point of view of science at any rate (we shall have much more to say about consciousness later). Wigner is replacing one ill-defined entity, measurement, with another, science.
The interpretation of the measurement process that comesclosest to a direct translation of the mathematical formalism of quantum theory is the many-universes theory. This theory, originated by Hugh Everett in his Ph.D. thesis, states that every time a measurement is made, universes in which the measurement came out one way are differentiated from universes in which it came out another way. In the example of Schrodinger's cat, what the many-universes theory suggests is that there are universes in which the cat lives, and universes in which the cat dies. These universes are blurred together; there is originally no distinction between them. But then, when someone opens the box and looks, the universes split apart: there are some universes in which the cat lived, and universes in which the cat died.
The many-universes interpretation does not add an extra step to quantum dynamics, nor does it appeal to extra-physical entities. It is, in David Deutsch's phrase, short on assumptions but long on universes. The ontological status of the alternate universes is not quite clear; nor is it clear when a measurement, which splits off universes from each other, should be judged to have occured.
Mind, Pattern and Quantum Measurement
Having presented the standard perspectives on quantum measurement, I will now present some less standard ones, leading up to an integration of physical and psychological perspectives on the universe.
First of all, the visionary physicist John Wheeler has taken an intriguing and ideosyncratic view of the problem of quantum measurement. While acknowledging the elegance and appeal of the many-universes theory, he rejects it because
[T]he Everett interpretation takes quantum theory in its present form as the currency, in terms of which everything has to be explained or understood, leaving the act of observation as a mere secondary phenomenon. In my view we need to find a different outlook in which the primary concept is to make meaning out of observation and, from that derive the formalism of quantum theory.
Quantum physics, in Wheeler's view, has uncovered the fundamental role of the observer in the physical world, but has not done it justice. The next physics breakthrough will go one step further, and place the observer at the center.
Wheeler also believes that the equations of quantum theory will ultimately be seen to be statistical in nature, similar to the equations of thermodynamics:
I believe that [physical] events go together in a higgledy-piggledy fashion and that what seem to be precise equations emerge in every case in a statistical way from the physical of large numbers; quantum physics in particular seems to work like that.
Thermodynamics deals with things like temperature and entropy, which emerge from the dynamics of large numbers of particles. No one particle in a gas has a temperature; the temperature comes out of the behavior of a large number of particles acting together. The famous Second Law of Thermodynamics, which states that entropy will always increase, that the universe is moving toward a state of disorder -- this also has no meaning on the level of individual particles, but only on the level of large "statistical" collections of particles.
Thermodynamics speaks of probabilities: it would only be definite if one had an infinite number of particles. Similarly, quantum physics speaks of probabilities. Wheeler's idea is that theories with probabilistic indeterminacy should come out of the study of large numbers of determinate objects. But what, exactly, are the more determinate objects out of which indeterminate quantum reaity is supposed to emerge? On this Wheeler is unclear, except to suggest that, one would want to see quantum-physical concepts arise out of some kind of non-physical substrate:
If we're ever going to find an element of nature that explains space and time, we surely have to find something that is deeper than space and time -- something that itself has no localization in space and time. The ... elementary quantum phenomenon ... is indeed something of a pure knowledge-theoretical character, an atom of information which has no localization in between the point of entry and the point of registration.
This hypothetical non-physical substrate, Wheeler has called "pregeometry." At one point, he explored the idea of using propositional logic (the logic of AND, OR and NOT) as pregeometry, of somehow getting space and time to emerge from the statistics of large numbers of complex logical propositions. However, this idea did not bear fruit.
Wheeler also suspects that quantum measurement has something to do with the social construction of meaning. He talks about the issue in terms of Niels Bohr's view of quantum phenomena. When does a quantum phenomenon, an uncertain, probabilistic thing, a combination of universes, become a real phenomenon, something definite and macroscopic?
I try to put [Bohr's] point of view in this statement: 'No elementary quantum phenomenon is a phenomenon until it's brought to a close by an irreversible act of amplification by a detection such as the click of a geiger counter or the blackening of a grain of photographic emulsion.' This, as Bohr puts it, amounts to something that one person can speak about to another in plain language....
Wheeler divides the act of observation into two phases: first the bringing to close of the elementary quantum phenomenon; and then the construction of meaning based on this phenomenon. The accomplishment of the first phase, he suggests, seems to depend on the possibility of the second, but not the actual accomplishment of the second. A quantum phenomenon, he suggests, is not a phenomenon until it is potentially meaningful. But if, say, the photoelectric emulsion is destroyed by a fire before anyone makes use of it, then the elementary quantum phenomenon was still registered. This is different from the view that the quantum phenomenon must actually enter some entity's consciousness in order to become a phenomenon.
Regarding the second phase of observation, the construction of meaning, Wheeler cites the Norwegian philosopher Follesdal that "meaning is 'the joint product of all the evidence that is available to those who communicate.'" Somehow, a quantum phenomenon becomes a phenomenon when it becomes evidence that is in principle available for communication.
Wheeler's views are intriguing, but the various parts never seem to come together to form a unified whole. On the one hand, quantum reality is supposed to be statistical, emerging from the behavior of a large number of "pre-geometric," perhaps logical entities. On the other hand, quantum measurement is supposed to be somehow social in nature, coming out of the registration of information in communities of human minds.
It has seemed to me for some time that there is a way to reconcile the two strands in Wheeler's thought, the statistical and the social. What is required is to consider things from a more psychological perspective. Wheeler frequently mentions propositional logic as a candidate for a a "pregeometry." From a psychological point of view, however, propositional logic is simply a crude, severely incomplete model of the process of intelligent thought. It represents an isolation of one mental faculty, deductive logic, from its natural mental environment. Instead of propositional logic, it seems more reasonable to suggest that the correct pregeometry is mind itself. Physics, one might argue, results from the statistics of a large number of minds.
In the psynet model of mind, to be discussed in Chapter 6 below, minds themselves are understood as patterns in physical systems. In this context, the positing of "mind as pregeometry" amounts to a kind of circular causation. Physical reality gives rise to physical systems, which give rise to minds, which in turn combine to produce physical reality. This is an intriguing and natural idea, which ties in with a great deal of spiritual philosophy. We will return to it in later chapters.
Yet another view of the measurement problem -- and the last I will discuss here -- was given by the great physicist Richard Feynman. Feynman, unlike Wheeler (who was his Ph.D. adviser), did not believe it was possible to understand quantum reality. He thought the realm of the very small simply surpassed our mental apparatus, which was after all built up from dealings with the everyday world. However, he was interested in finding useful "operational" ways of thinking about quantum reality, ways ofthinking that would be useful in the actual doing of science.
In a letter to a colleague Feynman proposed the following:
Proposal: only those properties of a single atom can be measured, which can be correlated (with finite probability) with an unlimited number of atoms.
What does this mean, in plain language? What a "correlation" is, in essence, is a way of predicting the behavior of a whole group of entities from the behavior of a small subset of the group. In other words, a correlation is a regularity; it is a pattern. A correlation in a collection of particles is a pattern in that collection.
I have already mentioned that, in the hyperrealistic, computationalist world-view, the world is made of relations, of habits, of patterns. What Feynman's approach to quantum measurement does is to extend this idea to the realm of physics. Feynman implies that, insofar as we can measure it, the physical world is made of patterns as well. Only patterns can be measured....
Think about it. "Only those properties of a single atom can be measured which can be correlated with an unlimited number of atoms." This implies that every property of a single atom which can be measured is actually a pattern emergent between the atom and other atoms. And how can one tell if a group of atoms are statistically correlated? Well, only by measuring them. But if "measuring" means "detecting a statistical correlation" -- then it follows that the atoms themselves are never directly measured, only certain "properties" that are in fact statistical correlations among large groups of atoms.
What are we to make of Feynman's reference to an infinite number of atoms? Obviously there is not an infinite number of atoms in the universe, so if taken literally this implies that measurements never exist. But if one thinks in terms of pattern, the role of the infinite number of atoms here is easy to understand. A correlation among an infinite collection of atoms is bound to be a pattern in the collection of atoms, no matter who is determining what is a pattern and what is not. But a correlation among only finitely many atoms is, to a much greater extent, a matter of opinion: some observers may recognize it as a pattern, while others may not.
Feynman's view implies that only emergent patterns can be measured -- that physical reality is known only through its emergent patterns. It also says something more specific than this: it says that only certain emergent patterns, namely correlations, are measurable. But the important point here is that correlations are indeed emergent patterns.
What this leads us to is a radical understanding of the relation between mind and reality. After all, if mind is pattern, and if all that we can physically measure are emergent patterns, then it follows that physical reality is in no way separate from mental reality. Insofar as we can measure it, physical reality is just a certain subset of the collection of patterns that makes up the mind.
This casts a new light on the Wheeler-inspired idea of mind as pregeometry. If mind and physical reality are made of thesame thing, pattern, then there is no logical problem in supposing one to emerge from the other. The physical and mental worlds are seen as two sides of the same coin.
Quantum Gravity and Beyond
All this may seem more than enough. But in fact, quantum reality as it is presently understood is just the beginning. Brand new developments in the area of quantum gravity give us even more striking insights into the interdependence of physical and spiritual reality.
To explain these developments, however, I must first digress for a moment to discuss the general character of contemporary physics theories, and in particular the notion of force. Aside perhaps from spacetime itself, force is the most important concept in modern physics (although it is not a particularly well-understood concept).
Essentially, a force is a means by which certain entities in spacetime push or pull on other objects in spacetime. The extent of the force between two objects depends on the positions and the motions of the objects. In addition, each separate force has to do with a distinct quality of objects; this is what distinguishes different forces from each other. For instance, the force of gravity depends on the mass of objects. The forces of electricity and magnetism depend on the charge of objects. The strong nuclear force, which has to do with quarks, depends on properties of quarks called color, charm and beauty. There are only four known forces in the universe: gravity, electromagnetism, and the strong and weak nuclear forces. The forces that we experience in everyday life -- wind, earthquakes, our own muscles, etc. -- are ultimately explained as consequences of these four forces.
It is forces which hold matter together in the form of coherent objects. Gravity keeps the solar system together. Weak and strong nuclear forces hold the nuclei of atoms together. And electromagnetic force holds different atoms together into molecules, molecules together into chemical compounds, etc. Electromagnetism is the most important force for understanding everyday objects, because it acts on the scale closest to our own, as opposed to the very small scale of nuclear forces, and the very large scale of gravity.
Newtonian physics gave laws of motion that were supposed to apply no matter what force caused the motion. Among the fundamental forces, however, Newton explicitly dealt only with gravitational force. Classical electromagnetism gave a Newton-like treatment of electromagnetic force. And classical quantum physics -- "quantum theory" proper -- deals only with the electromagnetic force.
Quantum electrodynamics or QED generalizes classical quantum physics to incorporate the ideas of Einstein's Special Relativity Theory (according to which quantities such as mass and length and duration exist only relative to the observer; and nothing can travel faster than light speed). QED does not deal with gravity, which is the province of Einstein's general relativity theory;nor does it deal with nuclear forces, the forces that hold together the nuclei of atoms. Modern unified field theories bring nuclear forces into the fold of quantum physics, by extending QED to deal with the weak and strong nuclear forces. The "standard model" unified field theory is the most general, widely accepted physics theory in existence. Beyond the standard model, one has the various theories of quantum gravity, including supersymmetry theory and superstring theory. These theories attempt to integrate gravity into the quantum-theoretic framework -- but none of them has yet been entirely successful, at this point. The progress of work in quantum gravity is held up by deep mathematical difficulties. As many theorists have observed, twentieth-century physics seems to require twenty-first-century mathematics.
Gravity plays a unique role in modern physics -- a role which may be difficult for the nonscientist to understand. Perhaps the simplest way to put it is that gravity destroys the separation of force from spacetime. Instead of forces acting within spacetime, as in classical quantum physics, QED, and the standard model, gravity requires that forces act on spacetime as well. This is an idea that shakes physics to its foundations.
Newtonian physics assumed a flat spacetime, but in the late 1800's, the mathematician Riemann began experimenting with the idea of a curved spacetime. Spacetime is four-dimensional -- three dimensions of space and one dimension of time -- and curvature in four dimensions is difficult to visualize. But Riemann showed that multidimensional continua can be curved, just like surfaces in two dimensions (where one has spheres and saddles as well as flat pieces of paper). The difference between flat and curved spacetime can be determined, among other methods, by looking at the behavior of parallel trajectories in space. In flat space, if two objects are moving in a parallel way, they will continue to do so, and will remain the same distance apart. In a curved space, though, this need not be true. Two objects can start out parallel, but wind up either colliding or moving further and further and further apart, depending on the curvature of the space.
Einstein, with his theory of General Relativity, showed that, in fact, physical spacetime is curved -- and that the curvature depends on the distribution of matter in spacetime. Matter curves space. What was previously thought of as the gravitational force, Einstein re-visioned as the gravitational curvature of spacetime. Newton had objects following straight lines in flat space, but Einstein had objects following special curved paths through curved space, called "geodesics." The geodesics of a space depend on the way the space is curved. So the path an object takes depends on the way the space is curved -- and the way the space is curved depends on the objects in space.
So, in Einstein's theory, instead of objects pulling on each other, objects curve spacetime, and the curvature of spacetime affects the curved paths on which objects move. This may seem to be a subtle distinction, but the point is that spacetime isno longer a fixed background against which forces act. It is, rather a part of the very action of forces. This is an astounding idea, and one that is still causing physicists a great deal of trouble.
The standard model, in contemporary particle physics, is a beautiful theory of particles acting on each other in spacetime, generating and destroying other particles by their interactions. It is amazingly evocative of the subtle realm of being as portrayed in Vedanta and other spiritual traditions. However, a large philosophical difference between particle physics and anandamaya is the presence, in the former, of an absolute underlying reality: namely, the spacetime continuum. In spiritual models of being, one has processes acting on each other, creating and destroying each other and fluctuating -- but there is no specifically structured space within which they are acting. They are acting within the formless Void, the shapeless Brahman. In the standard model, on the other hand, the processes in question are interacting within a particular four-dimensional spacetime. (Actually, in many models, particles are interacting in a higher-dimensional spacetime, which is then collapsed to four; but this is just a technical point.) Gravity essentially demands that physics be pushed further in the direction of anandamaya -- that the distance between quantum-maya and annamaya be made yet greater. It demands that the assumption of a fixed spacetime be abandoned, in favor of an understanding of spacetime as something that emerges from particle dynamics.
Stumped by the conceptual difficulties of getting spacetime out of particle dynamics, some physicists have studied a theory called "quantum physics in curved spacetime" -- a theory which is not quite quantum gravity, but is perhaps the next best thing. By taking curved spacetime as a given, this theory sidesteps the really difficult aspect of quantum gravity; but even so, it leads to some remarkable conclusions. For instance, just as relativistic quantum theory implies the inadequacy of the notion of a linear time axis, quantum theory in curved spacetime implies the inadequacy of our notion of space. One arrives at the remarkable conclusion that, if two observers are moving relative to one another, and both look at the same exact spot, one observer may see a particle there while the other does not. This means that, in curved spacetime, particles have no real existence. They exist only relative to the particular observer.
A small community of physicists, however, is attempting to take the problems of quantum gravity by the horns. Current quantum gravity theories being developed by David Finkelstein and Tony Smith at Georgia Tech fall into this category. Finkelstein's theory assumes no fixed spacetime, only particles fluctuating, creating and annihilating in a kind of a void; but unfortunately, it is so complicated mathematically that it is almost impossible to make definite calculations. Smith's theory is intuitively quite similar, but makes the purely provisionalassumption of a particular, very, very simple spacetime structure -- a discrete structure, in which particles can only exist at a finite number of different points. In Smith's model, it is possible to calculate the values of various physical constants. Work is underway to understand how Smith's particular spacetime structure can be seen to come out of Finkelstein's framework of total interdependence.
In sum, what the puzzle of quantum gravity shows is that the parallel between physics and the higher levels of being goes significantly beyond the oft-noted peculiarities of quantum reality. Quantum reality is only the beginning. Quantum reality is subtle, deeply interdependent behavior taking place against a fixed spacetime/reality. Quantum gravity, however, is subtle, deeply interdependent behavior which gives rise to an apparently but not fundamentally fixed spacetime/reality.
The central puzzle of quantum gravity is, therefore, much like the central puzzle of all wisdom traditions: how do the fixed rigid structures that we see arise out of the total formless flux of underlying reality? Modern physics, in its own very technical and arcane way, is coming to grips with the fundamental questions of mind, spirit and reality.