Why is this such a big deal?
If you have even a passing interest in science and technology, you’ve probably heard about quantum computers. Recent news headlines are ablaze with Google’s announcement of “quantum supremacy,” which they claim is likely to happen by the end of next year.
The researchers at Google believe they will develop a computer that can perform certain types of calculations that are not possible using traditional computers. This is astounding considering that a single quantum processor could outperform today’s fastest computer, the Chinese TaihuLight, which has over 10.6 million processor cores and performs over 59 thousand trillion operations per second.
But the main question on your mind probably is:
What is a quantum computer?
Simply put, a quantum computer performs computer operations with quantum bits, referred to as qubits, rather than classical bits.
This is a short definition, but I’ll admit it doesn’t really provide much of an explanation. Before you can understand qubits, you need to understand traditional bits. Also, you need to have a basic understanding of how a traditional computer works before you try to understand a quantum computer.
I’m going to be honest with you. Quantum computing is not an easy concept to grasp, even if you have a background in computer science. Nevertheless, I’m going to try and provide an easy-to-understand explanation so that anyone that happens upon this blog post will come away feeling like they have a decent grasp of the subject.
First, let’s start off with a brief explanation of traditional computers, the devices you interact with on a daily basis such as cell phones and laptops. As you may already know, the heart of your device – the part that does all the “thinking” – is the CPU, or central processing unit. It’s a little silicon chip composed of billions of microscopic transistors that each store a value of either 0 or 1. These values are called “bits.”
The idea here is actually simpler than you might think. The processor is designed to process combinations of zeros and ones called “bytes.” A byte consisting of 64 bits in varying combinations can have billions of different possible values.
The processor takes these combinations of 1s and 0s, referred to as binary code or machine language, and creates a binary file. This file can take the form of an image, text, or a series of logical actions that provide any kind of functionality you can imagine (otherwise known as a computer program).
The reason computers break down information into these binary bits is that a simple process of switching bits on and off (1 being “on” and 0 being “off”) can be done at incredible speeds, inputting and outputting information at an astounding rate. In fact, your laptop can process trillions of bits every second.
Actually, when you get right down to it, the computer is really not much different than the old telegraph machines that used a series of dots and dashes, but it does it over a trillion times faster.
So at this point you should have a basic grasp of how traditional computers work and what a classical bit is. Now we need to take a look at quantum computers and qubits.
What is a qubit?
No, it’s not that weird looking hose-nose guy that hops around on colored blocks (for the younger folks, this is a reference to the classic arcade game, QBert).
But anyway… instead of using classical bits to do the core number crunching, quantum computers use quantum bits – which are cutely referred to as qubits. These little suckers can do weird things using the bizarre properties of quantum physics.
Like traditional bits, qubits also processes 0s and 1s into binary code like a super-fast telegraph machine, but instead of being in a single state of either on or off, the quantum bit can store a value of 0, 1, or both at the same time.
Okay, this is where it gets kind of weird.
What we’re talking about here is individual atoms or even subatomic particles like electrons or photons that are being cooled to near absolute zero temperatures so scientists can make them act like transistors in a quantum processor.
I kid you not. This is not just theory I’m talking about here. These computers exist today and you can even buy one from a Canadian company called D-Wave if you happen to have a cool $20 million in cash lying around.
Of course, they are not yet able to do practical tasks like your laptop or phone, but research labs are using them as the basis for developing what will later become practical quantum computers.
But I’m getting ahead of myself here. At this point we’re trying to understand how the qubit works. In order to understand this, you need to understand that tiny particles like atoms and electrons are so small that the nature of reality itself starts to become “fuzzy.”
Quantum particles are not really individual “objects” as we understand them. You might imagine an atom as a little tiny marble, but the truth is it’s much weirder than that.
Quantum particles simultaneously exist as both particles and waves of energy. They can be in more than one place at the same time and they can be in various states simultaneously, such as spinning both clockwise and counterclockwise at the same time.
At this point you might be asking: “Huh?”
Well, that’s completely understandable. Quantum physics can be a hard pill to swallow. You might even think these scientists are serving up a load of, as Colonel Potter from M.A.S.H. would say, “horse-hocky.”
If you have doubts about any of this stuff, all I can say is check out the research. This is what they teach in physics classes at all the major universities in the world, so if that’s not good enough for you, then go back to watching pro wrestling.
Such is the bizarre and puzzling world of quantum mechanics — and because of these strange behaviors, tiny quantum particles can be used to perform tremendous numbers of calculations simultaneously. The reason quantum computers have far greater potential than classical computers is, when you combine the qubits together, not only can you get billions of combinations, but you can perform billions of different operations at the same time.
In fact, with a quantum processor composed of only 50 qubits, Google claims they will be able to solve problems that would be impossible for any traditional computer – even supercomputers that fill a room the size of a basketball court.
I’m not gonna lie to you – in order to really understand how qubits are used to perform quantum computer algorithms, you have to have a grasp of some very advanced mathematics, so I won’t even go there. The concept you need to take away from all this is parallel processing.
Parallel processing is simply when a computer executes multiple tasks at the same time. Traditional computers can do this by using multiple processor cores working simultaneously, but quantum computers do it with just one processor. In a quantum computer, each qubit acts like a parallel processor, which is possible because of their ability to be in more than one state simultaneously, such as spinning both clockwise and counterclockwise at the same time.
The advantage of parallel processing can be illustrated this way: imagine a mouse trying to find its way through a maze to find the cheese. A classical computer is basically one mouse that can run extremely fast, but it has to work its way through every nook and cranny of the maze to find the prize. It’s not too smart, but it works.
The quantum computer, when searching for the cheese, will not have one mouse, but many mice running around at the same time. A 50 qubit processor will have 250 (roughly 1.2 thousand trillion) mice all searching at the same time. That’s a lot of mice. Needless to say, with that many mice you will find that cheese a lot faster than with one mouse, no matter how fast that little guy can scurry around.
So now you know the difference – more or less – between classical bits and qubits. If you want to know how they build machines that turn individual atoms into bizarre parallel processing qubits, you could probably ask the guys in the top secret laboratories how they do it, but they might dredge up that old saying: “I could tell you, but then I would have to kill you.”
Whenever a major new technological advancement occurs, there are always pea-brained flat earth types that start preaching doom and apocalypse. There are two main scenarios that these types of people are talking about in regards to quantum computers, which I will hopefully debunk in this section.
“Quantum computers are the rise of Skynet”
First of all, if you are one of these people, I have to ask: You know that The Terminator was just a movie, right?
Yes, it’s true that researchers believe that quantum computers will make artificial intelligence and machine learning vastly more powerful than they are today – to the point where machines can think and act like human beings. That doesn’t mean that our laptops are going to sprout squiddy tentacles and fly around trying to exterminate human beings.
The point is, there is a vast difference between a machine that can solve problems as well as a human and a conscious entity that feels the need to wipe out a rival species inhabiting the same planet that it lives on.
And yes, there are respected scientists that believe machines will become far more intelligent than we are within the next several decades – and this may be true, but to think that such a machine will be hell-bent on wiping out humanity is born of pure neurotic paranoia — but I will admit it makes a good plot for a sci-fi flick.
Quantum computers are the end of privacy.
It’s true that there are many governments and organizations researching quantum computers for their ability to crack encryption codes that secure private information – after all, that’s how we beat the Nazis in World War II (see info on the enigma code or watch the movie: The Imitation Game).
In theory, a powerful enough quantum computer would be capable of cracking today’s encryption codes, whereas a traditional computer would take longer than the age of the universe to do it (the universe is estimated to be 13.772 billion years old).
If the wrong people were able to crack into every secure file in the world, it would be catastrophic to the point of sending human civilization into chaos. The banking system, which relies on encrypted files to secure the entire collective wealth of the world, would be rendered obsolete by people that could hack into any bank account at will.
Theoretically, this is possible, but we are many years away from developing a quantum computer that could carry out such a feat. What you have to realize is, encryption technology develops at the same rate as computer technology.
Consider how fast traditional computers have advanced. The computers today could easily hack into any encrypted information from several decades ago, but the encryption technology has advanced so much since then that it would be virtually impossible for even a supercomputer to break into a standard 256-bit encrypted file.
In fact, while researchers are racing to develop the first practical quantum computer, quantum encryption is also being developed to stave off potential threats of information theft.
Once again, the idea of worldwide collapse is only a product of misguided and uninformed imagination. If you are truly afraid of any of these scenarios, my advice is to look into obtaining a Xanax prescription.
A little bit of history
If you’re still reading this post, congratulations. It’s a somewhat challenging subject, and I haven’t tried to be brief in my explanation. Since I still have your attention, I think it’s only fitting that we give a little background on how the idea of quantum computing came about and the timeline of achievements that have led up to where the field is today.
The ideas for using quantum theory for computation purposes date back to 1960 with papers published by the Russian mathematician, Stephen Wiesner. At this time there was no feasible theory for a working quantum computer – that is, not until about two decades later.
The first person to propose a working model for a quantum computer was the famous physics theoretician, Richard Feynman. In case you haven’t heard of him, he is one of the most well-known figures in physics, akin to people such as Albert Einstein and Stephen Hawking.
Feynman did some of the most important work toward understanding quantum physics and developing the current model of subatomic particles. Not only did he introduce the concept of a quantum computer, but he was also the first person to introduce the concept of nanotechnology. These are the two most transformative technologies that are being developed today.
But I digress. Throughout the 80s and 90s there were many theoretical advancements toward the application of quantum computing, but none of it was put into practice until 1997 when the first quantum computations were carried out using 2 qubits with a technique called nuclear magnetic resonance (NMR). However, in 1999 it was shown that this NMR technique was not a “true” quantum computing method and would not have any advantage over classical computers.
It was later discovered that in order for a quantum computer to be superior to a classical computer it would need to use a quantum behavior known as entanglement, which is when two particles become linked together as if they are one object.
What scientists have observed from this phenomenon is that the entangled pair of particles will always mirror each other’s state, no matter how far apart they are. This is what Einstein famously referred to as “spooky action at a distance.” The reason this is necessary in quantum computing is that when quantum particles are observed directly they revert from a quantum state to a regular state, which means they lose their ability to be in multiple simultaneous states (this is referred to as a superstate).
In 2008, a Canadian company called D-Wave developed a 128 qubit quantum computer that they made available for sale to the public, and shortly afterward, Google, NASA and DARPA purchased D-Wave quantum computers for research. There is some debate about whether these systems truly function as quantum computers. Consequently, Google and other research organizations have continued to improve the technology to a point where it can produce indisputable results.
Google’s quest for “quantum supremacy”
Google had been secretive about their efforts in quantum computer research after purchasing the D-Wave system, but in 2016 the tech giant announced they were on the verge of creating the first quantum computer that would prove that the technology exists to perform calculations that are impossible for traditional computers. This accomplishment is what the company termed quantum supremacy.
If Google is successful — and leading researchers believe they will be — it will spark a revolutionary new interest in the technology industry to begin utilizing quantum computing technology.
With the dawn of the quantum computing age right around the corner, this means that we will see some radical changes in the way we interact with computers. Pretty soon they will understand conversational language the way people do.
As computers begin to solve problems more like humans, they will soon be able to improve their own programming at increasing rates. This recursive self-improvement will eventually lead to an artificial intelligence that is far more advanced than human intelligence. When this exists, it becomes impossible to predict what new advancements will follow. This new era where human intellect is eclipsed by AI is what famous scientist Ray Kurzweil refers to as “the singularity,” which I will post an article about in the near future.
This is my first post on this blog and it has been a lot of fun talking about an exciting new field of science that is on the verge of changing life as we know it. I’m eager to hear your feedback and don’t hesitate to correct any inaccuracies I may have placed here. I’m in this for a learning process as much as providing an information resource for intellectually curious people.