In the quantum world view, events in reality cannot be pictured as coming in predetermined, connected sequences of cause and effect, but they aren’t random either. All events can now be seen as governed by rules of probability. Which subatomic particles will jump to other energy levels at any given nanosecond can be described only by laws of probability; all larger events are shaped by those subatomic particles.

Normally, an event or an object seen at our level of reality is the average of quintillions of subatomic events. Most of the time, the events we see at our level, the macroscopic one, are high-probability macro events, and they fit together to create the classical, Newtonian pictures and patterns we’ve seen over and over and have come to expect of everyday life.

But quantum theory leaves open the possibility that once in a while, when enough unusual events at the subatomic level coincide, they cause an event at our level—a hurricane, a supernova, a tornado, an avalanche, a failed bolt in an airplane, a mutation in a bacterium, or a sillytumble (okay, I made that up). None of these events is “uncaused”; they all have causes. The problem with the Newtonian worldview is that the causes aren’t neat sequences of earlier events. In principle, we can’t predict these outcomes in advance because we can’t calculate the sums of all the influential links in the causal chain. Weird things can, and sometimes do, happen.

And it’s not just that too many factors are involved. Even simple Newtonian systems with only two or three objects and forces acting on them evolve in ways that defy our best computer models. The possible results of the system depend on initial conditions of all parts of the system. Miniscule changes, some of them quantum changes, in any of these parts at any time during the unfolding of events may lead to any one of zillions of very different outcomes. The possibilities rapidly become, in practical terms, incalculable.

          

                                     

                                          

                                             inside the eye of Hurricane Katrina (credit: Wikipedia) 

For example, we can only say after the hurricane has passed that five days before it hit, some of our models had been indicating near-certainty levels of the hurricane’s making landfall on the Florida Coast. Then, the evolving odds that it was going to hit a specific site—for example, Pensacola—began to approach 60 percent on Friday and 95 or 99 percent by Sunday. Tiny jumps by particles, even some subatomic ones (what physicists call the “butterfly effect“), right back to the hurricane’s genesis off the coast of Africa, favoured and eventually selected one outcome over all of the other possible outcomes.³

In this hurricane scenario, gradually, a winning-outcome candidate emerged. But before it hit, which outcome that would be was not just unknown; it was unknowable. Unlike the Newtonian/Enlightenment world view, the quantum worldview says that the outcomes in real-life sequences of events are in principle never certain, but are always to some degree predictable in the exact sense of that word.