worked. Science and the Church now had their own fiefdoms. The Newtonian–Cartesian view was that the cosmos is essentially a giant machine. Originally scientists paid a bit of lip service to the Deity, but essentially they viewed the universe as a giant, self-sustaining, three-dimensional game of billiards. If you knew the masses and speeds of each object, you could perfectly predict future positions and behavior, or even extrapolate in reverse and know where everything had been.
Similarly, in the next century, French mathematician Pierre-Simon Laplace surmised that if someone had sufficient intelligence and information, they could know everything about the universe just by observing the current positions and trajectories of all objects. Everything was determined by previous conditions. No mystery remained except, perhaps, for the small matter of ultimate origins. Not even God was necessary; indeed, Laplace omitted any mention of a deity in his writings on celestial mechanics.3
Such was the view of reality in the closing moments of the nineteenth century and early years of the twentieth. Each side pretty much kept its bargain. Science left religion alone and ignored consciousness as well. And religion considered science to be okay—after all, it explained how things moved and didn’t trespass into trying to figure out why or how the cosmos came to be.
As the Western world gained in living standards and concomitantly grew less religious, the scientific deterministic model became the new gospel. It was often called scientific realism, and who could argue with such a label? You’d have to be a nutcase to be antiscience or antirealism.
In sum, the universe was widely regarded as objective (existing independent of the observer), made of matter (which included energy and fields), ruled by causal determinism, and limited by locality. When it was even considered at all, consciousness or the observer was assumed merely to be part of the physical matter-based cosmos, having somehow arisen from it. That its origins or actual nature couldn’t be explained seemed to bother no one. A few lingering mysteries were deemed perfectly compatible with the material universe.
And this is where we’d still be if it weren’t for quantum mechanics.
That new branch of physics started quietly enough. Not much couldn’t be explained by classical physics until the closing years of the nineteenth century, but puzzles were starting to grow. Some were just plain odd. For example, a bonfire and the Sun were both deemed to be blazing fires. (The Sun’s true energy-releasing process of nuclear fusion wasn’t explained until Arthur Eddington did so in 1920.) If you stood too close to a bonfire while holding out a hot dog or a marshmallow on a stick, you’d jump back because your skin could grow painfully hot—certainly more uncomfortable than solar rays ever make you feel, even at midday. And yet despite the ample heat, a bonfire can never deliver a tan or “sunburn.” But why? This was unexplainable.
We’d known about ultraviolet (UV) rays since their discovery by Johann Ritter in 1801, and that such UV photons (bits of light) coming from the Sun are what produce suntans and sunburns. But why didn’t we ever get any from a campfire? Classical physics said that UV should be present, and hanging out long enough around a campfire should deliver a tan. But it never did.
The answer had to do with electrons, which were discovered in 1897. They were immediately assumed to orbit around an atom’s nucleus like planets around the Sun. But here’s the thing: In 1900 Max Planck surmised that electrons can absorb energy from a hot environment, and then radiate it back in the form of bits of light, which ought to include some ultraviolet light. But if electrons—unlike planets, which can orbit the Sun at any distance at all—could only orbit their atom at specific, discrete locations, then they would only be able to absorb or emit specific quantities of energy, called quanta because it takes a precise amount or quantum of energy to move an electron a specific distance. If the environment wasn’t energetic enough, electrons would only be able to make easy jumps, like those in the atom’s outer fringes. They’d never be able to make a powerful jump from the innermost orbit to the next highest, which is what’s required to create a UV photon when the electron fell back down again.
Planck’s idea, soon called the Planck postulate, was that electromagnetic energy could be emitted only in specific quanta. It wasn’t long before Niels Bohr, the brilliant Danish physicist, confirmed that all atoms indeed behave like that. Only by falling back inward from one allowable, higher orbit to another one closer to the nucleus do atoms emit packets of light, called photons. This is the only way in which light is born. If an atom is not stimulated, its electrons remain in stable orbits, and it produces no light at all.
That high-energy drop from the second orbit to the innermost one—needed to create a sunburn-producing UV photon— requires a more powerful initial energy boost than a campfire can provide. Quantum theory—the idea that electrons can make only specific moves between allowable orbits and thus absorb or emit only specific quanta of energy—explained previously enigmatic facets of nature. So far, so good. But weirdness was already lurking in the closet. According to Bohr, an electron cannot exist in any intermediary position outside a precise, allowable orbit; anytime it changes position it must go from one specific orbit to another, and never be anywhere between them. So here’s what’s odd: As an electron changes orbits, it does not pass through the intervening space!
Imagine if the Moon behaved like that. It used to be much closer to us, and is still moving farther away at the rate of almost two inches a year. It’s spiraling away like a bent skyrocket. Also, physics allows the Moon to be any distance from us. Now imagine if the Moon didn’t budge in its separation from us for millions of years, but then, in an instant, suddenly vanished and rematerialized in a new location fifty thousand miles farther away. And imagine, too, that it accomplished that jump in zero time without passing through any of the intervening space.
Well, that’s what electrons do. Needless to say, this opened bizarre new implications and set the stage for earthquakes that rocked classical physics forever. Even Planck unsuccessfully struggled to understand the meaning of energy quanta. “My unavailing attempts to somehow reintegrate the action quantum into classical theory . . . caused me much trouble,” he wrote with exasperation many years later. Ultimately he gave up trying to make logical sense of it, or even trying to convince his most stubborn doubters. “A new scientific truth does not triumph by convincing its opponents and making them see the light,” he said presciently, “but rather because its opponents eventually die, and a new generation grows up that is familiar with it.”
But it was hard for anyone to get too familiar with quantum mechanics because strange new revelations kept arriving. Physicists learned that light, as well as bits of matter, are not just particles but also are waves, and how they exist depends on who’s asking—meaning, the method of observation determines how these objects appear! Actually it’s worse than that. These entities can also exist in two or more places at once, in a kind of blurry probabilistic fashion. We might say that electrons acting as waves are really wave packets, and where the packet is densest is where an individual electron is most likely to materialize as a particle. But it may also, upon observation, pop into existence in an unlikely place, on the almost totally empty fringes of that packet. Over time, a series of observations will show electrons or bits of light materializing according to probability laws.
This means the electron or photon doesn’t enjoy any independent existence as an actual object in a real place, with a real motion. Instead, it exists only probabilistically. Which is to say it doesn’t exist at all—until it’s observed. And who observes it? We do. With our consciousness.
Suddenly, consciousness and the cosmos—which had parted paths way back with Aristotle, and whose divorce seemingly was made more permanent by Cartesian and Newtonian credos—might not be such totally separate entities after all.
Slowly, in the opening decades of the twentieth century, classical physics and the common-sense gospel of locality were eroding. After all, some “motion” unfolded without the object penetrating through any space or requiring the slightest bit of time.
Objectivity