Here’s everything about quantum computing using binary:
No, quantum computers do not use binary.
What makes quantum computers so powerful is that they can process more than two fundamental signals at a single type, meaning they can understand more than just 1s and 0s.
That allows them to scale exponentially, and quantum computers have overwhelming potential.
So if you want to learn all about how quantum computing works exactly, then you’re in the right place.
Let’s get started!
What Is Binary?
None of this explanation is really going to make sense unless we start at the beginning.
A lot of people know that computers use binary, but fewer have a strong understanding of what that really means.
In computer terms, binary refers to the number of signals.
There are two possible signals, hence the “bi” in binary.
Here’s the gist of how a computer works.
You have an electric circuit.
You can send a current through that circuit or not.
On the receiving end of that circuit is a component.
It will check to see if there is a current or no current.
If it sees a current, that is recorded as a “1.”
If there is no current it is recorded as a “0.”
Those are the two possible signals.
You can put ridiculous numbers of circuits next to each other, and the computer can process a whole lot of 1s and 0s at the same time.
But ultimately, everything a computer does is reduced to 1s and 0s.
Now, technically speaking, computers can use a lot of different mechanisms for signal processing.
That’s how you can have Wi-Fi, fiber optics, and a ton of other stuff.
The signal doesn’t have to be an electrical circuit; that’s just an easy example to follow.
Regardless of what actually carries the signal though, every computer is using this type of binary processing.
Either it sees a signal and records a 1, or it doesn’t see a signal and records a 0.
That’s it. That’s how binary works.
Does Quantum Computing Use Binary?
At least, that’s how every computer worked before quantum computing became a thing.
Now, there are quantum computers, and they are very definitely not binary computers.
They can process signals beyond 1s and 0s, and it’s a big part of what makes them so powerful.
I’ll get into how it all works in a bit, but there are a few things to know about quantum computers.
First, they’re very difficult to make.
There’s no one in the world anywhere close to making a quantum computer that you would keep in your house, much less in your pocket.
Also, because they don’t use binary, they’re a lot harder to program.
One of the biggest challenges in quantum computing right now is a concept called fault tolerance.
Basically, scientists and engineers have to completely rethink how to design computers in order to make quantum computers as reliable as traditional computers.
It’s proving to be a massive challenge.
Lastly, quantum computers have massive potential.
I’m going to explain a concept called quantum supremacy a little later.
The premise is that when quantum computers reach this stage, a single such computer will be more powerful than all of the traditional computers in the world combined.
Clearly, getting away from binary is a big deal for advancing computers.
How Does Quantum Computing Work? (3 Steps)
Alright.
I have very lightly covered the gist of classical or traditional computing.
Now, we’re going to dive into quantum computing.
As the name suggests, these computers are built on the concept of quantum mechanics, and unlike Marvel movies, that name isn’t there just to make it sound impressive.
As you might have heard, quantum mechanics is a pretty advanced topic in physics, so if you haven’t studied it all, then we’re about to go straight down the rabbit hole.
Bear with me.
I’m going to skip over the crazier bits of math, and there won’t be a pop quiz at the end.
But, I am going to teach you the essence of how quantum computers work.
#1 Superposition
Since this whole thing started with a question about binary systems, let’s talk about superposition first.
Superposition is a quantum mechanical phenomenon that allows something to be in two states at once.
That’s already a weird concept, but it’s also the key to getting past binary processing.
Let’s try an analogy.
Right now, you might be sitting in a room.
You can get up, walk through a doorway, and then you’ll be in another room.
Those are two different places, and you can’t be in both places at once.
But, under special circumstances, you actually can be in both rooms at once.
If you stand in the doorway with one foot in each room, then you’ve done it.
You’re in two rooms at the same time.
The physics of superposition is quite a bit more complicated, but here’s the gist.
Small particles, like an electron, usually have a specific state.
(If you really want to get into the physics, one of the best states to understand superposition is quantum spin, or the up/down status of an electron.)
If the electron is in the superposition state, you could make a computer that observes superposition as a third rudimentary signal.
The electron in the first state would be a 0.
The second state would be a 1, and the third state would be a 2.
Instead of operating in binary, you’re now in trinary.
That means you can store and process substantially more information with less hardware, and that’s one of the building blocks of quantum computers.
Here’s the bigger picture.
Quantum computers can offer a lot more than just one rudimentary signal.
Superposition is ultimately pretty complicated, and there’s not a hard theoretical limit on how many different signals a quantum computer could use.
Instead of 0, 1, and 2, it might go all the way up to a thousand—maybe higher than that.
The true potential of quantum computing is still immeasurable.
That said, modern quantum computers are focused on using superposition to have three basic signals.
But even this is an oversimplification, and that’s because there’s more than superposition going on.
We’ll get to that later.
How Does Superposition Work?
Superposition is a pretty big deal in all of this, so how does it actually work.
How do you get an electron, for example, to be in two states at once?
We’re actually getting pretty deep into quantum mechanics, so for those of you who don’t already have physics degrees, I’ll try to keep this light.
The gist is that particles are naturally in states of superposition.
If we go back to the idea of an electron, it can be in a state of spin up or spin down.
You don’t really need to know what that means, just that it can be oriented in two possible directions.
What quantum mechanics tells us is that an electron will actually be in both states until outside forces push it into one state or the other.
They’re in superposition to begin with, and it’s when we mess with the electrons that they “collapse” into the up or down state.
So, quantum computers are really just taking advantage of naturally existing superposition.
The engineering behind it gets incredibly complicated very quickly.
The gist is that the hardware is built around quantum theory and probabilities so that it can actually recognize when the particles in use (which are not necessarily electrons) are in superposition or not.
#2 Entanglement
That got deep, but superposition is actually the smaller part of what makes quantum computers so impressive with so much potential.
Entanglement is an even bigger deal, and it’s the primary reason why quantum computers can grow more powerful than anyone can reasonably predict.
Within quantum computing, entanglement is how qubits are arranged.
That’s already a bit of terminology, so let me back up for a second.
When we talked about a classical circuit, I told you that the computer can read whether or not a current is present to understand if it is seeing a 1 or a 0.
What I didn’t mention is that traditionally, computers will arrange eight of these circuits together, and when they do, it’s called a bit.
So a traditional bit has 8 nodes that can each read 1 or 0.
Then, you can arrange a bunch of bits together, and that’s how you build up your system.
Quantum computing uses something called a qubit.
In a basic sense, it serves the same function as a classical bit.
The qubit is the arrangement of information for both processing and data storage.
But functionally, the qubit is completely different from a classical bit.
That’s because of entanglement.
Qubits are quantumly entangled together.
What that means is that every time you add a qubit to a quantum computer, it exponentially increases the amount of data that can be processed and stored in the system.
Conversely, when you add a bit to a classical computer, it just adds eight more nodes that can only store a 1 or a 0.
#3 Bits vs. Qubits
This really starts to make sense if I get into some numbers and show you some comparisons.
Because a classical computer uses binary, the largest number you can represent with a normal bit is 256.
Now, modern classical computers use clever tricks to make them more efficient, and they can handle very large numbers at ludicrous speed.
But, you’re ultimately adding bits to the system, which raises the capacity by 256 worth of numbers at a time.
You need a lot of bits for a powerful computer.
Let’s simplify and say that a single qubit can store a 0 or a 1.
So, the largest number a single qubit can express is 2.
If you add another qubit to the system (we’re at 2 qubits now), then you actually increase the amount of information in the system exponentially (this gets pretty deep into probabilities, which is why I’m simplifying).
So, 2 qubits can express a number up to 4.
With 3 qubits, the number jumps to 8, and with 4 qubits, it gets up to 16.
This exponential scaling is everything.
It doesn’t take very many qubits before your system is expressing incredibly large numbers in incredibly complicated ways, and a quantum computer can handle that complication very quickly.
What this boils down to is that a quantum computer can achieve quantum supremacy with just 50 qubits.
From an engineering standpoint, that’s very hard to achieve, but from a theoretical standpoint, it’s not even scratching the surface of what a quantum computer could do.
Here’s something that might shock you.
IBM currently has a quantum computer with 127 qubits.
It has achieved quantum supremacy, but with a catch.
The hardware can do this, but not for very long.
On top of that, software and programming for quantum computers are still way behind that of classical computers.
So theoretically, the IBM computer could solve problems too complicated for all of the traditional computers in the world combined, but that doesn’t mean we’re ready to use it in that way.
Quantum computing still has a long way to go, but as far as hardware designs go, quantum supremacy is clearly possible, and kind of already here.
How Does Entanglement Actually Work in Quantum Computing?
Ok.
I’ve thrown a lot of physics at you, but there’s still a question hanging in the air.
How do you entangle qubits to make all of this work?
Naturally, there’s an incredibly complicated physics explanation, but there’s also a simple, practical explanation.
If you get two very small particles together (like electrons for instance), and you push them very very close together, they end up having to entangle.
The electrons want to repel each other because they have the same electric charge, so in order to handle being so close without going crazy, they enter into the weird state known as entanglement.
So, to build a quantum computer, you’re essentially smashing really small particles as close together as possible.
Easy, right?
