Most of us grew up and were educated in a world in which classical physics ruled as the basis for understanding reality. Of course this does not mean we all took high school physics class, but the scientific cornerstone for how we think of reality has been established in traditional classical physics.
Sure, we knew quantum mechanics was a thing out there among the brainiac set, but it was too esoteric for us normal everyday people to seriously consider. After all, quantum mechanics has a well deserved reputation for being hard to understand. It is beyond rocket science. It is really far out there.
Newtonian classical physics on the other hand was relatively accessible. Attainable that is to the extent that any disciplined science like physics is approachable to average folks. Classical physics has had a way of seeping from the halls of academia to the general population in that it has formed our conventionally accepted mindset respecting the nature of reality.
And what is this outlook? It can best be described by what western philosophy calls realism. In short, realism is the view that substance or material and the things made of materials belong distinctly to a world and universe external from ourselves. Objectivity is the guiding principle. Reality is objective. It is detached from our subjective perspectives. We are merely observers to a reality that was here before we were born and will be here after we die. Or so we are led to believe.
Underpinning this objective and mind-independent notion of reality is a belief in immutable laws of nature as posited by Isaac Newton and his followers. Indeed, this is science at work. We are unquestioningly convinced by the scientific elite that a deterministic set of motions and rules sprang forth from the Big Bang which has continued to shape the universe ever since. And then to be told by them that something is a law, as in Newton’s laws of motion, says in a stern voice, “This is how IT IS, period!”
When a cause and effect interplay occurs predictably resulting in a well defined materialist or energetic action, such as a drought lowering the water level of a pond, we see it as evidence of reality demonstrating what it does naturally. To us it is common sense. However, strongly implied in this observation is that reality has a fixed and steady quality to it. Change, when it happens, is just part of the interaction of basic elements, but underneath it all exists a permanent and enduring lay of the land.
Quantum mechanics is now trickling into the common way of thinking about what is real, albeit slowly, after one hundred years of its being on the scene. The influence of quantum mechanics is becoming profound, especially regarding the way it calls into question the permanence of realism. Quantum mechanics introduces uncertainty where before there was consistency and reliability. We have come to learn that reality is probabilistic rather than assured. The universe may be unfolding as it should, but it is doing so in way that is not so easily discerned.
Indeed, it is in the area of quantum measurement where we run into ambiguity. In quantum mechanics there is a principle known as superposition, which states that the subatomic wave-particle (the basic quantum entity) abides in many different states concurrently until a measurement is attempted. Upon calculation, one of the multifarious conditions of the wave-particle is recorded. Had time or space or the means of measuring been different, then another computation could have been yielded.
In short, there is no single and invariable assessment that can be made about a wave-particle. The measurement could have been any one of many possibilities.
Superposition therefore suggests that the very practice of measuring reality at the quantum level actually creates the reality seen by the observer. Measurement no longer computes a primeval or pre-existing state of affairs. Instead measurement reveals one out of many possible views of reality. Materials it seems do not have well defined and fixed traits. Rather reality requires that an observer be present to register that reality exists, or at least one perspective of reality.
Quantum mechanics raises the possibility that how we have thought about reality may be defective. Philosophical realism has not yet reconciled itself with the superposition principle of quantum mechanics. It is hard to see how these two schools of thought will ever harmonize. What we thought was a clockwork universe governed by physical laws is now called into question.
The implications of randomness and uncertainty being fundamental aspects of reality are far-reaching. What else does this call into question? Is Truth now also erratic? Are values fickle and unstable? Will anything last in perpetuity any longer? When the very essence of reality is called into question, then so also is the world we thought we knew.