In 2022, physicists Alain Aspect, John Clauser, and Anton Zeilinger were awarded the Nobel Prize in physics for declaring once and for all that the universe is only locally real. This new claim of quantum theory is, quite understandably, insanely outlandish to anyone outside the scientific field. How is it possible that reality is conditional? I feel very real, sitting here, typing my thoughts away on my computer. I’m sure that you feel very real reading this article, which I thank you for doing, by the way. But neither of those things feels like it should be conditional. As Rene Descartes famously said, “cogito, ergo sum.” “I think, therefore, I am.” But is reality not also conditional in that very statement—that we must be thinking beings to exist? Who are we if we are not beings with thought? Do we exist at all?
To really comprehend this thought problem, it is necessary to travel back in time to understand the groundwork of physics. And no, I don’t mean to Albert Einstein, though we will get to him. I mean all the way back to ancient Greece. Philosopher Parmenides asserted that “there is only the being, but nonbeing does not exist.” This may seem like an intuitive observation. How could nothing exist?
But, Parmenides’s assertion was in direct conflict with the forefather of physics and chemistry, Democritus, who proposed that all matter is composed of infinitely small, indivisible particles he called atomos, or atoms. The nature of an atom, a particle flying through space with random motion governed by the laws of physics, necessitates the presence of a void, the existence of true nothing. This is an incredible presumption that we perhaps take for granted today. In high school science classrooms, you often hear that you cannot truly touch anything because there is a small infinity of space between your hand and the object you wish to touch. This is a result of that void, that nothingness, that atoms are spinning through.
Regardless of the question of the void, we know one thing is real, and that is matter itself. We know this because atoms are quantifiable. Properties about them can be known with certainty. They are made of protons, electrons, and neutrons, and the electrons have quantized energy levels, or a set of energetic values that can be known. To be known, to have concrete properties that are true at all times, regardless of observation, is a function of reality itself. Furthermore, physical phenomena are primarily local. In other words, I cannot exert force on you from behind my computer screen because you are not locally near me. And while there are forces that are non-local, like gravity and magnetism, Einstein’s theory of relativity parses out the details of this phenomenon. No matter how you slice it, reality is real. Einstein famously said, “God doesn’t play dice.” That is, God doesn’t deal with possibilities and probabilities. There is a concrete yes or no for everything.
Or so we thought.
The description of reality in physics means that an object or phenomenon has to have a defined set of properties. For instance, I have brown hair. The only way I could have blonde hair is if I changed it.
But quantum mechanisms and the quantum model of the atom deal with probabilities. This is most famous in Erwin Schrödinger’s cat thought experiment. A cat, a flask of poison, and a radioactive source are placed in a sealed box. If an internal monitor (e.g., a Geiger counter) detects radioactivity (i.e., a single atom decaying), the flask is shattered, releasing the poison, which kills the cat. The Copenhagen interpretation of this thought experiment implies that, after a while, before anything is known to have happened, the cat is simultaneously alive and dead. Yet, when one looks in the box, one sees the cat either alive or dead, not both alive and dead, collapsing all other possibilities into one single actuality. This quantum superposition essentially restates the age-old question: if a tree falls in a forest and no one is around to hear it, does it make a sound?
Einstein, of course, believed that this idea of quantum superposition – that two realities could exist simultaneously – was ludicrous. Alongside other renowned physicists like Boris Podolsky and Nathan Rosen, Einstein argued that quantum superposition was a paradox and the description of physical reality provided by quantum mechanics was incomplete. Reality exists regardless of the presence of an observer listening to the tree fall in a forest or watching the cat die. How could it be otherwise?
In order to really challenge Schrödinger’s hypothesis, Einstein, Podolsky, and Rosen (EPR for short) proposed their own paradox of quantum entanglement. To walk through this experiment, let us consider a pair of electrons. If they occupy the same orbital (that is, pattern of electron density in an atom or molecule), three of their quantum numbers – the energy, shape, and orbital level – will be the same. What makes them distinct electrons is their spin. One electron will be a spin-up electron, and one will be a spin-down. Before the electrons are observed, they are in quantum superposition, meaning they could either be spin-up or spin-down, just like the cat in the box could be dead or alive. Since this is a binary decision, an observer only needs to know the spin of one of the electrons to automatically know that the other electron in the pair will have the exact opposite value. This fact remains true regardless of the distance between the electrons. This thought experiment is extraordinary because it implies that an observer can know information about an object that is not locally real to the observer himself.
This is quantum entanglement. The question then becomes, is the state of both of these electrons static and unchangeable?
For example, let’s say I had two bouncy balls: one red and one blue. I close my eyes, mix them up, and ship one to you and one to someone else. If you open the box and find it is a red ball, we know the other ball has to be blue. Einstein would say that the ball I mailed to you was red and has always been red. But quantum mechanics would say that it was only red at the moment of observation. If you had opened it and it had been blue instead, the ball would have had to communicate information to the other ball to make sure it was red at that same instance. This would break both the law of locality and the idea that anything can travel faster than light since this situation assumes that information can travel faster than light. The EPR group thought that there must be some sort of ‘hidden variables’ at play to cause such a phenomenon to happen. There must be something we haven’t discovered yet to explain quantum entanglement without losing reality and breaking down physics.
The 2022 Nobel Prize winners systematically broke down the EPR paradox to show that, yes, indeed, quantum entanglement is real, and the act of observing a phenomenon is what causes the wave function to collapse. The finer details of the experiment are complex, and you can check out this episode of Quirks of Creation to learn about them in greater detail. But suffice it to say that what these physicists demonstrated shook the foundation of quantum mechanics and, perhaps, reality itself. If it is true that if a tree falls in the woods and no one is around to hear it, it doesn’t make a sound; if it is true that particles have certain probabilities of speed, velocities, and positions, but we can’t truly know anything, and they do not have any properties before being observed to collapse the wave function, does that not make reality subjective?
I do not think so because science is leaving out a factor that it simply cannot account for. This is the hidden variable that Einstein missed all along, the variable that holds our bodies together, not just on a cellular level but also on an atomic level. And that is God.
The foundation of all of science, especially physics, is philosophy, especially in these greater questions about who we are and the purpose of our existence. Unfortunately, in the modern age, we have sloughed off the questions of philosophy to focus on the material, the things we can see and detect and know concretely. The beauty of the uncertainty of quantum mechanics is that it takes science back to its roots – to the main question of who we are and why we are here. The uncertainties drive us to search for the truest of certainties, for a Being who transcends space and time, the author of the laws of physics, the one who set the stars in motion, THE Great Observer.
For God, all times are simultaneously present, all things are known, the past is just as real as the present, which is just as real as the future. Quantum mechanics, in its way of uncertainty, allows us earthly creatures to peek behind the curtain, if only for a moment, to see just a tiny fraction of the quantum superposition that God bears witness to second by second, day by day.
And so, perhaps both Schrödinger and Einstein are right – so much of our physical existence is probability dependent on an observer. But the hidden variable is that the Great Observer exists, making reality concrete across all of time and space regardless of whether you or I observe it since someone else outside of this realm is observing it all.
We are just beginning to scratch the surface of our universe. And while mankind may have found that there is a great deal of randomness and variability in quantum physics, at the deepest root, we have not seen and cannot detect and may not ever be able to detect a reality so real that it would be painful for us to know or recognize it. A reality so real that it surpasses human logic and understanding.
