In spite of which, de Broglie’s matter-waves were confirmed when beams of electrons were fired at a crystal. The crystal lattice is, in effect, a series of slits, and slits cause light rays to bend (diffract). The electron beam diffracted just as if it was a light beam. And so, in an experiment performed later, did a beam of neutrons. Particles did behave like waves.
By 1927, no fewer than three complete ‘quantum theories’ had solved Bohr’s impasse. They were proposed by Werner Heisenberg, Paul Dirac and Erwin Schrodinger
In 1925, on a holiday in Heligoland, Heisenberg decided to forget Bohr’s ‘solar system’ atom, and concentrate on the mathematics. He pictured atoms as oscillators, or vibrators—rather like those mattresses that are supposed to induce relaxation. What he wanted to find was some connection between vibrations and the lines in light spectra. He finally succeeded in finding a mathematical formula that would describe all the states inside the atom. Heisenberg had broken the code of the spectrum. He was so excited that he left the house at 3:00 in the morning and spent the rest of the night sitting on top of a tall rock.
There was one point that troubled Heisenberg. In his quantum mathematics, p times q did not equal q times p, thereby apparently violating the laws of arithmetic (p and q stood for the position and momentum of a particle). This problem was solved when news of Heisenberg’s breakthrough reached a Cambridge graduate student named Paul Dirac, a brilliant mathematician, who saw immediately that the paradox could be explained in terms of the work of a Dublin mathematician of the nineteenth century, William Rowan Hamilton. Hamilton had been working on this problem of whether light is made of waves or particles, and had produced a set of equations that would describe the motion of a wave or a particle, and in which A times B did not equal B times A.
Erwin Schrödinger, a physicist of the old school, was unhappy with this new tendency to turn quantum physics into complicated algebra; he continued to believe firmly that it ought to be possible to visualise an atom. During the Christmas of 1925, on holiday in the Tyrol with his latest mistress (he was a famous womaniser), Schrödinger had a sudden inspiration. Brooding on de Broglie’s ‘matter-wave’, he produced a wave formula, which he called by the Greek letter psi (), and which allowed him to think of an electron wave in the same terms as a wave on a pond. Or, rather, imagine a ball of dough which begins to dance to syncopated music, and shoots out waves as it does so; this is a crude approximation to Schrödinger’s atom. Schrödinger’s wave function was regarded as the greatest advance so far in quantum physics.
At first sight, these three great breakthroughs sounded contradictory; in fact, Schrödinger himself recognised that they were three statements of the same basic ideas.
It was Dirac whose ‘quantum algebra’ produced the next major breakthrough. One of his equations, dealing with an electron moving at almost the speed of light, had a plus as well as a minus in it, and seemed to predict the existence of a positive particle similar to the electron (which has a negative charge.) In due course, the positron was discovered in the laboratory, earning Dirac the Nobel Prize.
But by then another vital principle of quantum physics had been discovered by Heisenberg—the famous ‘uncertainty principle’. Superficially, this sounds unremarkable. What Heisenberg stated—in 1927—was simply that it is impossible to measure both the position and the speed (momentum) of a particle. It sounds unremarkable because it seems to be a merely practical limitation. To measure the speed and position of a billiard ball requires simply that you shine a light on it (otherwise you cannot see it), and then measure how long it takes to get from A to B. You cannot shine a light on an electron because it is too small; all you could do would be to make a single photon bounce off it, which would be like hitting the billiard ball with a golf club, and would obviously affect your measurement.
An analogy from everyday life might help. Imagine a behavioural psychologist writing a book about human behaviour (classical physics is a kind of behavioural science), and beginning a chapter on sex by explaining that it is an appetite exactly like eating and drinking. But, having embarked on this analogy, he realises that sex is in some respects quite different from the appetite for food. A starving man may die; no sex-starved man ever died from lack of sex. Starting from this recognition, he may end by grasping that sex, unlike food, is 90 percent ‘in the mind’, and cannot be understood as a purely physical need. His position could then be compared to Bohr’s recognition that an atom is not a ‘thing’.
And in that same year, 1927, Niels Bohr dotted the i’s and crossed the t’s of Heisenberg’s uncertainty principle. In discussions with Heisenberg, he produced what is known as the Copenhagen Interpretation, or the Principle of Complementarity. He said, in effect: forget whether an electron is a wave or a particle. If we ask an electron about its position (which is a particle property) we get an answer that suits a particle. If we ask it about its momentum (which is also a wave property) we get an answer that suits a wave. Stop asking which is correct, and recognise that the two answers complement each other.
In other words, not being able to measure both the speed and position of a particle is not just a practical limitation: it is inherent in the nature of reality itself.
Another quantum physicist, Max Born, had interpreted Schrödinger’s wave function psi as a measure of the probability that the electron would be in one place or another. Schrödinger had protested, and made his point with his famous illustration of a cat locked in a box with a cyanide capsule. A quantum process—like radioactive decay—can trigger a hammer which may or may not smash the capsule and kill the cat. According to Born, said Schrödinger, the cat exists in a state that cannot be described as either alive or dead—until someone opens the box. And that, he said, is plainly absurd.
And yet that, in a sense, was exactly what the Copenhagen Interpretation was saying. Observing a subatomic process causes a collapse of the wave function, and makes it turn into a particle. But, before the wave function collapses, the electron is in a state of probability, which cannot be pinned down more accurately.
Einstein objected bitterly. He agreed with Schrödinger. Something is really happening inside the atom, even if experimental limitations prevent us from discovering what it is. ‘God does not play dice’, he said indignantly.
He devised a ‘thought experiment’ to disprove Bohr—it is known as the Einstein–Podolsky–Rosen paradox, or EPR. Suppose, he said, two electrons collide at the speed of light, and bounce off in opposite directions. It would be possible to measure the speed of one and the position of the other; and since they are virtually identical—except for flying in opposite directions—this would amount to disproving the uncertainty principle.
Not so, said Bohr. The two electrons are part of the same system, so, if you cause one wave function to collapse, you cause both to collapse at the same time.
No, said Einstein, for since they are travelling at the speed of light, and it is impossible to exceed the speed of light, one particle cannot possibly know what is happening to the other.
But this argument was won by Bohr. In 1982, a group in Paris, led by Alain Aspect, carried out the two-particle experiment, and discovered that Bohr was correct. If you cause one photon to swerve upward at an angle of 45 degrees, the other will swerve downward by 45 degrees. So it would seem that, like identical twins, the photons somehow feel connected, even when flying apart at the speed of light. This also confirmed the work of the Belfast scientist John S. Bell, who had arrived at the same conclusion mathematically. (It is popularly known as ‘Bell’s Inequality Theorem’.)
There is one more step in this argument—a step that to the ordinary reader may seem to throw the whole question into hopeless confusion, yet brings us back, once more, to the problem of the nature of UFOs.
There is one particularly baffling experiment that underlines the Alice in Wonderland paradoxes of quantum physics. In its simplest form, it is known as the double-slit experiment. If I shine a beam of light through a narrow s
lit, with a screen on the other side, it will form a slit of light on the screen. If I now open up another slit at the side of the first, two overlapping slits of light will form on the screen. But there will be certain dark lines in the overlap portion, due to interference—the crest of one wave cancelling out the trough of another.
Now suppose that the beam is dimmed so that only one photon at a time can pass through either of the slits, and suppose that, instead of a screen, you have a photographic plate. Over a long period, you would expect two slits of light to appear on the plate—but no interference lines, since one photon cannot interfere with itself. Yet, when this experiment is performed, the result is still two slits of light with interference lines.
There is something stranger still. If a photon counter is placed over the two holes, to find which is used by each photon, the interference effect immediately vanishes, as if being watched made the photon behave itself.
How can this be? Does the photon split into two? Or does the wave somehow divide, and pass through both holes? If so, why does it hit the screen in a precise spot? And why does it behave like a wave when unobserved, and a particle when observed?
In the 1950s, Hugh Everett, a pupil of the physicist John Wheeler, suggested a bewildering interpretation. The fact that the photon becomes solid only when it is ‘watched’ suggests that, when it is not being watched, it still takes the form of Born’s ‘wave of probability’, and can go through both pinholes at the same time. And the two ‘waves of probability’ interfere with each other. It is as if Schrödinger’s cat existed in two universes at the same time, dead in one and alive in the other. Once the box is open, the two possibilities coalesce in our solid universe, and it is either one or the other.
But why just two universes? When a photon makes a choice between wave and particle, it is not, according to Everett, making a real choice: it is choosing both in parallel universes. And since an electron wave coalesces every time it collides with a photographic plate, or another electron, this implies a new parallel universe every time—thousands, in fact, billions, of parallel universes.
The idea sounds like a joke. Yet many scientists take it seriously. For example, a younger member of the quantum-physics establishment, David Deutsch, devotes a chapter in The Fabric of Reality (1997) to explaining the double-slit experiment, and speaks of ‘tangible’ photons and ‘shadow’ photons—the former existing in our universe, and the latter in parallel universes.
Aristotle had a concept called ‘potentia’, a strange realm that exists between possibility and actuality. It begins to look as if electrons—and cats—are perfectly comfortable in this realm.
The purpose of this detour into quantum physics is to make the point that, whether we like it or not, we have to learn to see reality in a completely different way. Like our sense of beauty, like our sense of humour, like our sexual preferences, reality lies mainly in the eye of the beholder. The physicist John Wheeler has even gone so far (in what he calls ‘the Participatory Anthropic Principle’) as to suggest that we create the universe in the act of perceiving it.
This is, of course, the notion to which Einstein objected so indignantly. Yet Einstein himself had played a central part in creating this new universe of physics in which the observer is all-important. And, by declaring that Planck was right about quanta of energy, he started a landslide that ended by carrying him away—cursing and shaking his fist.
Now it is true that this revolution has not yet affected you and me. We go about our business as if we lived in the old, solid universe of nineteenth-century physics. (In fact, a recent survey showed that one-third of all people in England and America do not even know whether the Earth goes round the sun or vice versa.) But it has, for example, troubled certain physicists, like Fritjof Capra and Fred Alan Wolf, and their books The Tao of Physics (1975) and Parallel Universes (1988) are devoted to a science that is becoming daily more like Eastern mysticism. We may also recall that, when Stanislav Grof’s subjects were given large doses of LSD, they also had insights into the nature of reality that sounded like classic Eastern mysticism. Gary Zukav says the same thing in his book The Dancing Wu Li Masters (1979). We do not know it yet, but we are walking around in a different universe—a universe that seems to have very little connection with what we regard as common sense. We are in the position of one of those Walt Disney characters, who walks over the edge of a cliff, and carries on walking—until he looks down, and suddenly begins to fall.
The amusing irony is that all this has happened as a result of a problem we discussed earlier: that, at a certain point in its development, humankind chose the way of the left brain—practical advancement, leaving mysticism and psychic faculties to its tribal shamans. This choice is responsible for modern science and civilisation; it is also responsible for our tunnel vision and feeling of inadequacy. And now, absurdly enough, modern science is telling us that we suffer from tunnel vision, and that, if we want to understand the universe, we shall have to remove the blinkers.
Now it cannot have escaped the notice of readers that the UFO problem has brought us to exactly the same point. It began by looking quite solid and understandable. Kenneth Arnold’s flying saucers raised the question: are we being observed by visitors from another world? Is it possible that the aliens are trying to prepare us for a mass landing on our planet?
Faced with that question, Jacques Vallee and John Keel quickly came to the conclusion that something altogether stranger was going on. Vallee concluded that it is a ‘control phenomenon’—that is, that an important part of its purpose is the effect it has on us. And it was as if a problem in classical physics changed into a problem in quantum physics.
And what is the effect it has on us? John Mack speaks of ‘the inconsistency between these [abductee] experiences and the consensus reality’, and adds, ‘There is no way, I believe, that we can even make sense, let alone provide a convincing explanation of this matter within the framework of our existing views of what is real or possible’.[1]
In other words, if an important part of the purpose of these phenomena is the effect on us, then that purpose would seem to be to decondition us from our unquestioning acceptance of consensus reality.
In many cases, that deconditioning can be both traumatic and strangely exciting—as epitomised in the case of John and Sue Day, who, on the evening of 27 October 1974, left the home of Sue’s parents, and set out on the forty-minute drive home to Avely, in Essex, where they intended to watch a play on television. Their three children, aged eleven, ten and seven, were in the back of the car. Their ten-year-old boy was the first to notice that an oval-shaped blue light was flying above them; they assumed it was an aeroplane. Then things became strangely silent, and, as they drove into a bank of green mist, the car radio began to crackle and smoke; John pulled out the wires. Then the engine went dead and there was a jerk. A moment later, they were driving again, and for a moment John had the odd impression that Sue was no longer present, and said, ‘Is everybody here?’ before he realised she was beside him.
When they reached home, they found the TV screen blank, and the clock showed that it was nearly 1:00 a.m. They had lost over two hours.
After this odd experience, the Days showed personality changes. John became more self-confident, more creative, and began writing ‘poems about life’. Sue also became more self-confident. And the ten-year-old, who had been backward at reading, suddenly improved. They became vegetarians and almost gave up drinking. John, who had been a heavy smoker, gave up smoking.
Then poltergeist activity began to take place in the house. The back door flew open violently and crashed against the wall. Items would vanish, then reappear days later. There were unaccountable smells, such as lavender. Finally, under these bizarre trials, John had a nervous breakdown and lost his job.
When he heard a radio programme about UFOs, he contacted the researcher Andy Collins, who went to the house in Avely, and also witnessed poltergeist phenomena. Collins introduced John to a hypnotist
named Leonard Wilder, and, under hypnosis, John began to recall what had happened. To begin with, Sue was unwilling to be hypnotised, but began to recall spontaneously; later, she submitted to hypnosis.
John recalled a white light surrounding the car, and a sense of rising. He seemed to lose consciousness, then found himself on a balcony in a kind of hangar. He was looking down on a blue car which he recognised as his own, although his own was white. Two people were asleep in the front, and more in the back. Sue, who recalled standing beside him, saw John and her ten-year-old standing beside the car, although they were also beside her on the balcony. (John Spencer has suggested that this seems to indicate that the Days were actually undergoing an out-of-the-body experience.)
John was taken to an examination room, where he lost consciousness, then woke up on a table, being scanned by some apparatus. Three tall beings were watching, and two small, incredibly ugly creatures, rather like traditional goblins with huge ears, beaked noses and triangular eyes, were examining him with penlike instruments.
The tall beings wore silvery one-piece suits, and communicated by what John assumed was telepathy. When the examination was over, they showed John the rest of the craft, and the recreation area and the control room. In the latter he was shown images of the solar system (which flashed by very fast), and a holographic image of a planet that had been destroyed by pollution. Finally, left alone in another room, he was startled when an incredibly beautiful woman walked in, then vanished. At this point, he found himself back in the car.