The Experiment that Changed the Universe

The famous two-hole experiment goes straight to the core of quantum physics. It's been performed so many times, with so many variations, it's conclusively proven that if one "watches" a subatomic particle or a bit of light pass through slits on a barrier, it behaves like a particle, and creates solid-looking bam-bam-bam hits behind the individual slits, on a final barrier that measures the impacts. Like a tiny bullet, it logically passes through one or the other hole. But if the scientists do not observe the particle, then it exhibits the behavior of waves that retain the right to exhibit all possibilities, including somehow passing through both holes at the same time — and then creating the kind of rippling interference pattern that only waves produce.

Dubbed "quantum weirdness," this 'wave/particle' duality has befuddled scientists for nearly a century. Some of the greatest physicists have described it as impossible to intuit, impossible to formulate into words, impossible to visualize, and as invalidating common sense and ordinary perception.

But the key question may be: waves of what? Back in 1926, German physicist Max Born demonstrated that quantum waves are waves of probability, not waves of material, as his colleague Schrödinger had theorized. They are statistical predictions. Thus a wave of probability is nothing but a likely outcome. In fact, outside of that idea, the wave is not there! It's intangible. As Nobel physicist John Wheeler once said, "No phenomenon is a real phenomenon until it is an observed phenomenon."

Until the mind sets the scaffolding of an object in place, until it actually lays down the threads (somewhere in the haze of probabilities that represent the object's range of possible values) it cannot be thought of as being either here or there. Thus, quantum "waves" merely define the potential location a particle can occupy. When a scientist observes a particle it will be found within the statistical probability for that event to occur. That's what the wave defines. A wave of probability isn't an event or a phenomenon, it is a description of the likelihood of an event or phenomenon occurring. Nothing happens until the event is actually observed.

In our double-slit experiment, it is easy to insist that each photon or electron, since both these objects are indivisible, must go through one slit or the other. Thus it seems reasonable to ask which way a particular photon really went. Many brilliant physicists have devised experiments which proposed to measure the "which-way" information of a particle's path on its route to contributing to an interference pattern. They all arrived at the astonishing conclusion, however, that it is not possible to observe "which-way" information and the interference pattern of a wave. One can set up a measurement to watch which slit a photon or electron goes through, and find that it goes through one slit and not the other. However, once this kind of measurement is set up, the photons instead immediately strike the screen in one spot, and totally lose the ripple-interference design.

Apparently, watching it go through the barrier makes the wave function collapse then and there, and the particle loses its freedom to probabilistically take both choices available to it instead of having to choose one or the other.

The Copenhagen interpretation, born in the 1920s in the feverish minds of Heisenberg and Bohr, bravely set out to explain the bizarre results of the QT experiments, sort of. It was the first to claim what John Bell and others substantiated some 40 years later: that before a measurement is made, a subatomic particle doesn't really exist in a definite place or have an actual motion. Instead it dwells in a strange nether realm without actually being anywhere in particular. This blurry indeterminate existence ends only when its wave function collapses – meaning the moment of its materialization into an actual entity. It took only a few years before Copenhagen adherents were realizing that NOTHING is real unless it's perceived.

If we want some sort of alternative to the idea of an object's wave-function collapsing just because someone looked at it, and avoid that kind of spooky action at a distance, we might jump aboard Copenhagen's competitor, the "Many Worlds Interpretation" (MWI) which says that everything that CAN happen, does happen. The universe continually branches out like budding yeast into an infinitude of universes that contain every possibility no matter how remote. You now occupy one of the universes. But there are innumerable other universes in which another "you" who once studied photography instead of accounting did indeed move to Paris and marry that girl you once met while hitchhiking. According to this view, embraced by such modern theorists as Stephen Hawking, our universe has no contradictions and no spooky action: seemingly contradictory quantum phenomena, along with all the personal choices you think you didn't make, exist today in countless parallel universes.

Which is true? Experiments of the past decade point increasingly toward confirming Copenhagen. And this strongly supports the idea that there is no independent universe outside the act of observation. Or, put another way, the universe and consciousness are correlative.

The above has been adapted from my book Biocentrism, written with Robert Lanza, MD, and published by Ben Bella in May. It is also excerpted in the current Discover magazine.