What I’m implying by the title of this post is actually the opposite. Something quantum is very, very small (subatomic), but practical applications of quantum mechanics are huge. Limitless, really. The trick here will be for us not to bring about our own extinction as a species before we’re able to realize all the benefits of applying quantum mechanics to more aspects of our daily lives. Before your eyes glaze over, and you exit out of this post because you think this is going to be some difficult physics thing, please give me a chance to explain.
First of all, you don’t need to know the math to understand, on an intuitive and theoretical level, what physics is, nor do you have to be able to do calculus to appreciate quantum mechanics. Indeed, I don’t know the math. And I’m not going to learn the math. Ever. At this point, it would just get in the way. As a 52 year old, I highly doubt that my future career will include being a physicist, which is similar to any prospects I may have in the NHL, but that doesn’t mean I don’t love the hell out of playing hockey. As the saying goes, don’t miss the forest for the trees.
Despite the fact that we’ve elected idiots like this guy:
and this nitwit:
scientific subjects like climate change can be as easy to boil down as this: “if you heat up water and then put your goldfish in it, will the fish like it?” or as difficult as you can handle. For example, positive feedback loops, the albedo effect, the carbon cycle, and the greenhouse effect can be incredibly complicated, but in this day and age, not at all incomprehensible. Pretending not to understand, like so many Republican lawmakers do, doesn’t make it go away, or be untrue. And climate science isn’t just one discipline. It’s hard to categorize, (although it’s unfortunately very easy to “cherry pick”) because it’s made up of so many different branches of science, like biology, chemistry, geology, physics, oceanography, paleoclimatology, and other “ologies.” Thankfully, there are a lot of people out there who not only understand “the science,” but who are actively engaged in doing really important stuff with all those amazing discoveries.
Physics is like dessert, for me at least. I enjoy every bit of it. It takes me places (both real and imagined) that transcend even our planet. As you probably know, there are four fundamental forces in nature: the gravitational force, the strong force, the weak force, and the electromagnetic force. The strong force, the weak force, and the electromagnetic force can be explained through something called, “the standard model,” which is a mathematical description of the elementary particles of matter and the way they interact with those 3 forces; however, this cannot be applied to gravity, which is, by the way (and somewhat counterintuitively) the weakest force of all.
Quantum mechanics (which is a theory, like gravity) was conceived of by Albert Einstein in 1905 when he realized that light had the ability to act as both a particle and a wave, and thus be quantized into discrete units of energy. In the 1920’s, Einstein’s friend, Erwin Schrodinger ** further developed the theory with his own equation (called the Schrodinger equation) describing what happens to a particle, or system of particles, when they are in a wave and then “collapse,” or are observed. The theory of quantum mechanics was further developed from there, with the purpose of understanding what goes on in the realm of atomic and subatomic particles (so that would be the very, very small). This is sort of the “flip side” of classical physics, which includes Newton’s laws of motion, and James Klerk Maxwell’s theory of electromagnetism, which deal with the big stuff, much like (Einstein’s) general relativity and gravity. Think of it like this: if you have a big sheet of rubber which is being held up off the ground by a bunch of people, and someone drops a bowling ball onto it, it will bend, or droop down, in the center. That’s an example of classical physics, with large phenomena which can be directly observed that affect stuff like orbits, black holes, gravity, and the warping of space-time (which is an example of what that bowling ball does). The super tiny stuff which takes place at the subatomic level, and which cannot be seen with the naked eye is part of quantum mechanics (which, by the way, is the same as quantum physics).
You can “quantize,” or measure basically everything but gravity into discrete, or indivisible, units. Many people have been trying to quantize gravity, but as yet, it hasn’t been achieved. There have been attempts to “unite” those four fundamental forces of nature for nearly 100 years, which physicists call a “unified theory,” or, “the theory of everything,” or TOE. This is something that Albert Einstein was working feverishly on right up until the day he died. His own general theory of relativity dealt with gravity – so that’s the really big stuff, not the very small stuff. His famous equations, like E=MC², wouldn’t apply to the quantum world, which really bothered him. For him, it was like the physics of the “very large” had a different “language” and set of equations from the physics of the “very small.” To Einstein, this was unacceptable. Some people think that Einstein was bothered by the randomness of quantum mechanics, or that he didn’t “believe in it.” They misinterpret his saying that, “God does not place dice with the universe,” to mean something entirely different than what he meant. The fact that quantum mechanics appeared random, disorderly, and unpredictable signified (for Einstein) not that it was actually any of those things (random, disorderly, and unpredictable), but that it appeared this way to us because we didn’t really understand what was going on at a much deeper level **. It’s all a question of how far down (or up) you want to go to understand something.
Take a gas cloud, for example. It looks pretty random, right? But that’s just at one “level.” If you think that it (the gas cloud) is just behaving randomly at the level you’re observing it, you’re right, but if you want to look deeper, the gas cloud has molecules behaving in incredibly complicated, and yet entirely predictable (and fully explainable), ways based on their molecular composition and their temperature. So, yes, the quantum world appears random and whacky, but, as Einstein strongly believed, that was only because we don’t understand it at its deeper (and deepest) level. Physicists have been working on untangling and “seeing” those layers, or levels, ever since Einstein began working on his own TOE [Side note: there are plenty of physicists who would argue that they don’t need to fully understand “why” things get so hinky at a subatomic level. They choose to simply exploit the fact that this happens and utilize it in a common sense and applicable way].
In the past century or so, getting truly down to the “bottom of things” has so far been unachievable, although string theory, superstring theory, M-theory, and other very complicated and somewhat tortured equations have been postulated in order to “see” what connects the really small with the really big. This bridging of the gap between the micro~ and macro~ world would, in fact, make it possible to explain the really big and the really small in the same sort of “language,” using the same set of mathematical equations. I’ve personally been fascinated by string theory for years, which is something that attempts to quantize gravity, which would then unify all the fundamental forces in nature, again, bridging the physics of the “big” (i.e., gravity, black holes), with the (quantum) physics of the very small (subatomic building blocks of the universe). String theory tries to explain every single thing in the universe (and what happened before the Big Bang) using vibrating filaments of energy, called strings, which come in a (now) infinite number of shapes and configurations (Calabi-Yau manifolds). Imagine something with 10 dimensions + time (so that’s 11 dimensions). It hurts the brain to conceptualize but it’s so cool! I’ll just say one more thing about string theory. String theorists needed some truly mind-blowing math to determine what would be the correct number of dimensions when working on this theory. They ended up realizin that math in the old journals of Indian mathematical genius Srinivasa Ramanujan (who died in 1920). There’s an upcoming movie about him called, “The Man Who Knew Infinity.”
I really (FL) quantum physics!
Here are three important ideas in quantum physics: 1) quantum tunneling, 2) the uncertainty principle, and 3) quantum entanglement.
Quantum tunneling is so incredibly cool. It means that particles can tunnel through a barrier that you wouldn’t think they could get through and end up somewhere else. As crazy as this sounds, it’s true. Quantum mechanics says that if, for example, you drop a raw egg from the roof of your house, the vast majority of the time, it will splatter on the ground BUT eventually, if you kept dropping eggs from the roof of your house for an infinite amount of time, eventually the egg would just keep going, maybe all the way through the Earth, or at some point, it would/could bounce up and out of the Earth’s atmosphere, or some other really bizarre thing.
If you can imagine it, no matter how crazy it sounds, quantum tunneling says it’s not only possible, but it’s actually happening somewhere, at some time. I’m not making this up. Here is a YouTube video about quantum tunneling. And a recent discovery of water doing something bizarre (quantum tunneling) was reported. The Scientific American article about it (which can be read here) says that it’s a “new state” for water, sort of, meaning that it’s not water as a solid, gas, or liquid. Probably saying it’s a “new state” is not right, but that’s just a technicality. Here’s another article which appeared on the website Motherboard about that same discovery. If you noticed the orange asterisks (**) a few paragraphs above, I put those there so you could scroll up and find that spot because this new water “state” being lauded in the media is much like what Einstein deeply believed to be true about the quantum world. It isn’t that water has a new “state.” It’s that we had not (previously) been able to observe it at this “level,” in the quantum world, where it has always been doing this.
The uncertainty principle, also called the Heisenberg uncertainty principle, means that you can’t know the exact position (on the atomic level) and the exact momentum of an object at the same time (here is a short YouTube video about this concept). It’s got to be one, or the other except that the more precisely you know the momentum of something, the less you can be sure you know the place, or position (of that same thing). And the way that “you know” the thing about a particle is by observing it. This is super important (in quantum mechanics). Once you observe something (or measure it), the wave collapses into a particle and it’s “decided.” Imagine a game of musical chairs (this visualization helps me a lot).
If you’ve heard of Schrodinger’s cat, who is both dead and alive (until you observe which one it is), that’s the same Schrodinger who I wrote about a few paragraphs above (I put two green asterisks ** next to that so you can find it), and that’s the same theory. So, in purely non-mathematical terms, the thought experiment goes that if you put a cat in a box with a vial of poison set to be released at some unknown time, and you don’t know if the poison has been released or if it has not yet been released, this means that you don’t know if the cat is dead or alive until you observe it. In other words, until you observe “it” by potentially opening up the box and looking inside (thus making the wave collapses into a particle, and into “one certain thing”), the cat is both dead and alive. Here’s a YouTube video about “that cat.” The cat is just a metaphor. They didn’t really do this to a cat, which is why it’s called a thought experiment. Einstein was, by the way, infamous for his thought experiments, which he called, gedankenexperiments. These intellectual meanderings led to some of his most incredible breakthroughs, including the finite speed of light, his theory of gravitation, and ideas about special relativity.
Quantum entanglement means that stuff is connected to “other stuff.” It may mean that a speck of dust floating in front of your face is actually, somehow, connected to a speck of dust all the way across the entire universe. Quantum mechanics has shown that such entanglement exists. Einstein called it, “spooky action at a distance.” And it is. Here is a YouTube video which explains quantum entanglement. Which leads me to a recent scientific achievement…
One of the most exciting and cutting edge applications of quantum mechanics involves quantum computing. Given what you have just read about quantum mechanics, the newest scientific achievements in quantum computing will hopefully make a lot more sense, particularly regarding quantum entanglement. As you may already know, classical computing is done with bits of information which are either 0’s or 1’s. Very important word here is, “either.” In the world of both classical physics and classical computing, you can’t a system, or data, “in” both 0’s and 1’s concurrently. But in the quantum world, thing behave differently, much like Schrodinger’s wily cat, who is both dead and alive until “observed,” which causes the wave to collapse into a particle and be “fixed” in place. Again, remember the game of musical chairs where everything is in play until the music stops (“wave collapses into a particle), and then the position settles.
In quantum computing, information is stored in something called a qubit (instead of just a “bit” like in classical computing). If that qubit is protected from any (and I mean absolutely any) outside interference (think: “observation”), then it remains in that superposition of both 0’s and 1’s (think: Schrodinger’s cat being both dead and alive until observed), and the data, information, and system remain intact.
All particles must be either fermions (named after Italian physicist Enrico Fermi) or bosons (named after Indian physicist Satyendra Nath Bose). There are three known fundamental types of fermions called Dirac, Weyl and Majorana. Until recently, the last two had not been observed, but there was a lot of evidence for their existence in condensed matter systems. Majorana fermions can be bound to a defect at zero energy, and then the combined objects are called Majorana bound states or Majorana zero modes which can be in a superposition of both 0’s and 1’s without being (easily) interfered with. This name (Majorana zero mode) is more appropriate than just calling it a Majorana fermion because it no longer behaves like a fermion. Majorana bound states are an example of non-abelian anyons: interchanging them changes the state of the system in a way that depends only on the order in which the exchange was performed.
Recently, teams of physicists, led by Charles Marcus who heads the Center for Quantum Devices (known as QDev) at the Niels Bohr Institute at the University of Copenhagen have been attempting to actually braid qubits (I’m not even kidding). The physicists showed that the two majoranas become non-interacting exponentially fast as they are separated which is necessary for them to be “protected” from coupling to the environment. Physicists believe that such braiding will be a huge breakthrough because it will show that Majoranas are a new kind of particle that can “remember” if two of them went around each other. There’s literally nothing else like that in the world.
Fermions know if you swap two of them, which yields a minus sign. Bosons don’t care at all. Anyons pick up a phase (a phase describes a state, like a solid phase, liquid phase, and a gas phase) when you swap them: move one in a loop around the other and you actually change the state.
It’s extremely difficult to keep the system “stable” and, essentially, protect it from outside interference which would cause something physicists call, “decoherence,” which just means that the wave collapses into a definite value (because it’s observed, or measured, right?). A recent article appearing in Gizmodo summed it up nicely:
“Physicists have devised ingenious methods in recent years for quantum error correction by exploiting the phenomenon of entanglement. This lets them check the data without making any actual measurement, thereby preserving the superposition. But what if you could have built-in protection from outside interference, making error correction unnecessary? That’s the idea behind topological quantum computing, the focus of Charles Marcus and colleagues at the University of Copenhagen’s Niels Bohr Institute, bolstered by a major investment from Microsoft’s Station Q initiative.”
Imagine, for a moment, that you have this Majorana zero mode particle in a nanowire in a quantum computer (I’ve made one up and put it just below this paragraph). Oddly enough, the red parts, which exist only at both ends of the nanowire (but not in the middle, so they’re not “touching”) are the only parts that would, against all odds, have to both be observed (interfered with), and, it would have to be at the same time, to actually interfere with the qubit and make it “decohere.” Again, decohere just means that the wave collapses, and the qubit becomes stuck into either a 0 or a 1. As long as both ends are not “interfered with,” the qubit remains both 0 and 1. Key word: “both,” which is a quantum thing:
Remember that once you observe (or measure, or interfere with) something in the quantum world, the wave collapses into a particle, and much like that game of musical chairs, everything becomes settled into only one place. In the case of classical computing, that means the information is then either stuck being 0 or 1, but by protecting against that interference, the quantum-ness of the information remains and it remains both.
The ultimate payoff for the modern world comes when quantum computers become a reality because they will not only make encrypted information far more safe from hackers, but quantum computers will also be able to perform exponentially more complex calculations and at incredibly faster speeds.
Here is a really good video from that Gizmodo article which I referenced above, and which, if it starts buffering, can also just be seen on YouTube. When they refer to anyons in the video, just think: Majorana zero mode particles (because this video is from 2014):
I actually know the physicist in the quantum computing story,
Charlie Dr. Charles Marcus. We went to high school together. He was 2 years ahead of me. He always looked very serious and very busy. I remember him wearing a bow tie, although this remains in dispute by Charlie who asserts that it cannot possibly be true because he doesn’t even know how to tie one (my response: “clip on”). I remember feeling very intimidated at that time by a bespectacled, (possibly) bow-tie wearing, and very serious senior boy. I’m not sure that I ever spoke one word to him during high school, however, in recent years, we’ve been in touch and I’ve actually gotten to know him better. Charlie went on to study at Stanford and then became a professor at Harvard. As I mentioned above, he’s now at the Niels Bohr Institute all the way in Denmark, which is a long way from where he came from. Here’s a picture of Charlie from high school (minus the disputed bow-tie):
And, just so I’m not hanging him out to dry all alone in the 1980’s, here I am from high school:
I’m pretty sure physics classes weren’t offered at our high school. If they were, I sure didn’t notice. I wish they had been because scientific breakthroughs are what keep me, personally, believing in my species, and they’re also what keeps me motivated not to give up on us.
As my second favorite physicist, Max Tegmark, says in his incredible book, “Our Mathematical Universe” (which led my kids and I to create two videos to enter into a physics contest Tegmark and his colleagues were conducting over at FQXI.org. This was in 2014 and we didn’t end up winning, of course, but the videos can still be seen here and here):
“My guess is that evolved life as advanced as ours is very rare. Our universe contains countless other solar systems, many of which are billions of years older than ours. Enrico Fermi pointed out that if advanced civilizations have evolved in many of them, then some have a vast head start on us — so where are they? I don’t buy the explanation that they’re all choosing to keep a low profile: natural selection operates on all scales, and as soon as one life form adopts expansionism (sending off rogue self-replicating interstellar nanoprobes, say), others can’t afford to ignore it. My personal guess is that we’re the only life form in our entire observable universe that has advanced to the point of building telescopes, so let’s explore that hypothesis. It was the cosmic vastness that made me feel insignificant to start with. Yet those galaxies are visible and beautiful to us — and only us. It is only we who give them any meaning, making our small planet the most significant place in our observable universe.”
Max Tegmark isn’t alone when he suspects that intelligent life may not be an inevitable part of evolution. In fact, it may go against any evolutionary bias. This makes the human species, in particular, and this very moment especially (since we may be shoving ourselves into extinction), so full of both promise, and peril.
I hope I’ve inspired you to learn more about quantum physics, on this, the 100th anniversary of the birth of Claude Shannon, who wrote his Master’s thesis (way back in 1948) about how all data could be reduced to either 0’s or 1’s. Which, thanks to scientists like
Charlie Charles Marcus is soon to be both 0’s and 1’s.
Further reading about quantum physics:
Brian Greene’s books, “The Elegant Universe,” “The Hidden Reality,” and “The Fabric of the Cosmos.” Most complicated: “The Hidden Reality.” I’ve also listened to all three of these books on audiobook (iTunes). “The Hidden Reality” is actually read by (narrated) by Brian Greene himself, which, in my opinion, makes it extra good.
Max Tegmark‘s book, “Our Mathematical Universe.” I’m not going to overstate anything when I say that this book changed my life. I never looked at the world, the universe, the multiverse, oncoming traffic, etc., the same way again. At some points, it gives you vertigo if you let yourself fall into what Tegmark proposes. Consider yourself warned. And if you think I’m kidding, here’s an Amazon.com customer review of this book (you can see my own response to the reviewer just below it) from 2014 in which the reviewer expresses a similar sentiment. I’ve also listened to this book on audiobooks (iTunes). It isn’t read by Tegmark, but it’s still very good.
John Gribbin’s, “Schrodinger’s Kittens and the Search for Reality: Solving the Quantum Mysteries.”
Steven Gubser’s, “The Little Book of String Theory.”
“String Theory for Dummies.” I know. It sounds stupid and easy to grasp. Think again.
Further reading about Albert Einstein and/or physics:
Nigel Calder’s, “Einstein’s Universe: The Layperson’s Guide.” This is some seriously heavy shit. It takes a long time to get through, but it’s worth it.
Brian Cox & Jeff Forshaw’s, “Why Does E=MC²?”
Alan Lightman’s two books, both mind-blowing: “The World You Thought You Knew,” and “Einstein’s Dreams.” When reading “Einstein’s Dreams,” which is a work of fiction, I absolutely promise that you will never forget it. Just don’t worry about the street names or geographical references, because that’s not what it’s about. If you just relax and get through the first few chapters (and this book is a very quick read…very short), you’ll see where he’s going with the concept.
Richard Berendzen’s audiobook (on iTunes), “Pulp Physics” is excellent. His mannerism and speaking style are extremely enjoyable and this is something you can listen to in the car, while exercising, or while doing something around the house. You’ll learn SO much that you never knew. I promise.
A book that can also change your life:
Stephen Greenblatt’s, “The Swerve: How the World Became Modern.”
YouTube video about quantum computers
“What can quantum computers do? (video)