Quantum physics for the masses

Update: Found a great video of Neil Tyson talking about human intelligence and quantum physics. It’s embedded below!

Disclaimer: I took one year of college physics and have read a handful of books on astrophysics and quantum theory. So of course I consider myself on par with Einstein, Heisenberg, and Hawking, and will unabashedly go forth into an academic field in which I have only wet my toes. Now that you know how conceited, sophomoric, and stupid I am for thinking myself anything other than a complete amateur, let’s move on to my hamfisted and flawed pseudo-scientific rant.

The physical world in which we live is far stranger than we’re normally aware of with our naked senses. Quantum theory, along with other advancements in physics of the last century, require some mental yoga to even get the gist.

Only a few days after writing down some of the initial ideas for this blog post, I heard a broadcast of To the Best of Our Knowledge on NPR, which interviewed Leonard Mlodinow, co-author of the recent Stephen Hawking book, The Grand Design. The interviewer introduces their subject matter of quantum physics by referring to it as “that famously weird, mind-bending science full of uncertainty and entanglement,” a good one-sentence summation of its bizarre implications. Near the start of the interview, Mlodinow makes the admission that “It’s basically incomprehensible. I mean, what does it mean that light is both a particle and a wave, or what does it mean that particles can influence each other from a distance. It’s mind-boggling, isn’t it?”

It is indeed mind-boggling, but I want to challenge the claim of “incomprehensible.” At least, no more incomprehensible or difficult to grasp than any other major leap forward in the history of physics. Quantum physics posits that one thing can be in two places simultaneously through superpositioning, light is both a particle and a massless wave, and string theory postulates that single dimensional bands loops on themselves to manifest what we know to be matter. “Mind-boggling” is indeed a good way to refer to modern physics.

And how can this all be? Quantum theory, and other fields in physics, explain phenomena which are not only counter-intuitive, but contradict themselves and seem downright impossible. When we observe behavior at an atomic level, it’s a completely different world from the one we know. But it is impossible to argue with the universe. It’s just that we aren’t wired for this invisible plane of existence; we’re wired for the scale of objects that can be picked up, walked upon, constructed, summited. Our minds, it would seem, are incompatible with some physical laws; they are not built to come to terms with what seems like nonsense.

Because of this, quantum physics and its absurd predictions are notoriously difficult to wrap one’s mind around. Because it is so counter-intuitive, we consider it a realm of understanding only for great thinkers and tenured professors.

But are not other truths of the universe counter-intuitive as well? For centuries, even with all the brilliant men that lived throughout those centuries, it was assumed (without bothering to test) that heavier objects fell faster than lighter ones. Until a quirky-minded individual named Galileo decided to perform the absurdly simple task of dropping two objects, and found that they hit the ground and precisely the same time, despite their weight difference. (Yes, the Pisa story is likely apocryphal, but it’s a good visual!)

And although we now know it to be incorrect, we can of course all sympathize with the Aristotelian belief that objects fall at a speed proportional to their mass. Drop a bowling ball and it slams onto the ground (or perhaps your toe) a moment later. Drop a paperback and it flutters to the ground where it lands with a plop. Drop a feather and, well, you get the idea. It’s what our brains naturally assume, based both on innate common sense, and experiential evidence.

This crude concept was, undoubtedly, very useful to the early human. Knowing that the boulder would not hesitate to crush you into a pancake was useful knowledge. Even observation confirmed our ancient ancestors’ assumptions: Snow elegantly floats to the ground, while heavy rain pelts into the mud.

So imagine the shift in thinking of the people of Galileo’s time. (Ignoring the fact that he was dismissed as a heathen by the faithful of his day. That is beyond the scope of this post.) Put yourself in that era, where you assumed your whole life that a shotput falls faster than a marble, and now some quack in Italy says they’ll hit the ground at the same time. And then, upon observing the phenomena, imagine having to wrap your head around the concept. It’s so contrary to how our brains are hard-wired. It’s software written in unfamiliar code. And there’s no immediately apparent reason for why these things behave the way they do.

And the list goes on. Ancient civilizations assumed the Earth to be flat (Who wouldn’t?), until it was noted, among other indicators, that the North star appears lower in the sky when traveling longitudinally. Aristotle said that the natural state of objects was to remain at rest, while Newton found that objects in motion stay in motion, unless acted upon by another force. Diseases were often attributed to evil spirits until the invisible world of microbiology was discovered, and simple hygiene measures saved countless lives. It didn’t seem possible that light could travel without some medium to allow its transit, and physicists once searched for an omnipresent “ether” in vain. And before our recent understanding of the mass energy equivalent, it was impossible to understand how the Sun could burn for so long without going dim (No such generous fuel was known to exist on Earth).

Another well-known misconception is the assumption of geocentrism (Once again we can thank our buddy Galileo, and his brotha from another motha, Copernicus). How could it be possible that the Earth spins, rather than the heavens revolving around us? After all, at high speeds, things go woooooosh! It’s completely foreign to our daily experience … the fact that things on this scale might behave differently is, again, a hard concept to understand. Today, every educated child knows, against intuition and immediate observation, that the Earth is racing through the vacuum of space. We’re cozily along for the ride, all up to speed with the planet’s enormously fast but elegantly regular rotation and direction. Of course, we don’t think about this fact through most of our daily lives, since it is not useful information to know that you’re barreling through orbit at 65,000 miles per hour while stuck in rush hour traffic.

Aristotle’s model of the universe

And speaking of the vacuum of space: the reptilian part of our minds understands space and air to be one in the same. How can there be “empty space?” If there were such a preposterous thing, what would it be? Could we even consider such a concept to even exist? But using relatively simple tools such as air pumps, men of Joseph Priestley’s time (who first isolated oxygen) laid the groundwork for our understanding of the atmosphere we inhabit, packed with gaseous matter, unlike the vast majority of the empty universe.

Similarly, the quantum concept of superpositioning is a seeming contradiction, just as empty space exists while nothing exists within it. This massless non-thing called space can be bent and contorted despite containing nothingness.

I’ve given several examples of concepts in physics which seem to not sit well with human understanding. And yet, these counter-intuitive concepts are taught every day in high school physics and third grade astronomy.

So why should the more recent theories of quantum theory and relativity, which have been considered notoriously mysterious to laymen, be reserved only for the imaginations and conversations of scientists? I very confidently believe that these more recent concepts are no more strange or difficult to understand than past advancements were when first introduced. It’s a problem of lacking context; one of the beauties of the universe is the depth of its complexity. The operation of its laws and the manifestation of its forces seem to keep getting stranger the more we understand, as every generation continues to tread into unmapped territory. Just like microbiology, a whole world of previously undetectable phenomena occurs on an atomic and subatomic level, rather than the much larger scale that our minds are accustomed to dealing with.

Because advances in technology that have recently allowed the precise measurement of this tiny world, we know these things to be the stubbornly consistent nature of the universe. The physical laws of this universe are what they are. The only reason we consider some of these laws to be “normal” is because they can be easily observed. Counter-intuitive though many of them may be, they can still be grasped just as we have come to terms with gravity and chemistry and washing our hands on our way out of the bathroom even though they don’t look dirty.

Without regard for the cause and focusing more on the state of things as they currently exist, we can say that the Earth is a sphere because it is a sphere. We can say that objects of different weight fall at the same speed because objects of different weight fall with an identical acceleration. Just as we can say that light is simultaneously a particle and a wave because it is simultaneously a particle and a wave. Even though we understand “things” as we know them to be one thing and one thing only, we must accept the reality of the way this thing occurs, against intuition, just as we accept that the world is not flat, against immediate intuition.

The nature of the universe is a uniquely intriguing delicacy, and there is no reason for us non-collegiate bigwigs to shy away from its fascinating implications. In Stephen Hawking’s eloquent words from A Brief History of Time, which I ripped off to a great extent in the paragraphs above, the nature of the universe “should in time be understandable in broad principle by everyone, not just a few scientists. Then we shall all, philosophers, scientists, and just ordinary people, be able to take part in the discussion of the questions of why it is that we and the universe exist. If we find the answer to that, it would be the ultimate triumph of human reason — for then we would know the mind of God.”


jedd goble

Cinematographer of Two Story Films. I'm passionate about film and the way that stories can shape the world and change our perspectives.