Quantum computing is an upcoming technology that will likely revolutionize what we can do, and even imagine doing, with computers. And the key to the power of quantum computing is qubits.
But what exactly are qubits and how are they powering the quantum computing revolution?
In classical computers, the coding units are bits – the binary zeros and ones we are familiar with. A collection of 8 bits can give you any single number between 0-255.
That’s pretty impressive in itself, and it’s always been how we measure computer coding in the modern era, so generation after generation we’ve grown up understanding that that’s how things were made, even as speed and computing power increased doubled and doubled as chips became faster and more efficient.
The cloud has changed the way we think about computing, particularly in terms of storage space and speed, but even there it hasn’t fundamentally changed how data is encoded.
Enter quantum scientists.
Buckle up — the next bit is necessarily complicated because it brings quantum physics to the data encryption side.
Quantum scientists study the world of infinitesimal particles of matter and the forces acting on them. It is important to understand that forces often act very differently in the world of very small objects than in the macrouniverse of comparatively “large” objects – the things we see, feel and touch we can (bless our naivety) think of the “real world” .
Things are going unexpectedly crazy in the world of quantum physics. Objects of this magnitude behave in strange ways, and two of these behaviors are key to understanding qubits in quantum computing.
Way 1: Quantum Superposition.
Quantum overlay is something that doesn’t make sense in the macro universe. It occurs where a quantum element, be it the spin of an electron or the orientation of a proton, can be in two quantum states at the same time.
In quantum physics, for example, an electron can be a particle and a wave at the same time. In the macro-universe this would of course be absurd – a fact pointed out by the quantum physicist Erwin Schrödinger when he invented the thought experiment “Schrödinger’s cat”. Schrödinger’s cat is the idea of putting a cat in a sealed box with a poison bottle, a source of radioactivity, and a Geiger counter. When a single atom decays in the radioactive source, the poison bottle shatters and the cat dies. If there’s no decay, no bottle will break and the cat will live to scratch your face when you finally let go.
Until you open the box, the cat is theoretically alive and dead at the same time.
So far, so fun, so reportable for the ASPCA. But what does all this have to do with qubits in quantum computing – right?
Qubits are so-called quantum bits. Let’s assume that qubits in quantum computing act like electrons in quantum physics and can have multiple values at once, unless you want to learn about orthogonal x and y basis states.
Take a moment, we’ll hit you in a moment with the second way qubits use the principles of quantum physics.
Way 2: Quantum entanglement.
Quantum entanglement is a phenomenon of quantum physics in which groups of particles are created and interact in such a way that they can only be described in relation to one another.
Put the two phenomena together in a qubit (which is ultimately a storage medium representing a two-basis quantum state – seriously, don’t start with X and Y basis orthogonals, you’ll never sleep again) and what You have a storage device that is faster than a quantum ball.
For example, remember that with the 0s and 1s of traditional 8-bit binary-based computers, you could get any number between 0 and 255?
With a qubit, you can get any number between 0 and 255 at once.
This means, for example, if we consider bits and qubits to be equivalent, individual storage units on different systems, a qubit gives you 255 times as much data per second as a bit can give.
Multiply that effect by the number of bits in a modern computer and you have an insanely fast, insanely powerful machine unlike anything we’ve seen before.
The unlocked technologies.
This will be important, because as we just enter the age of quantum computing powered by qubits, other transformative technologies are coming into play that happen to require insanely fast, insanely powerful machines to get the most out of them.
Everyone has heard of AI (Artificial Intelligence), and machine learning is an integral technology that powers the algorithms it depends on. These technologies are already making amazing changes in the world—medical breakthroughs, the digital transformation of business, improved imaging for everything from self-driving cars to long-range telescopes, and much, much more.
They manage this with standard, bit-based computer technology. Picture these technologies on an endless shot of ultra espresso, and you’re not even halfway understanding how transformative the power of quantum computing will be for AI and machine learning capabilities.
The power of quantum computing has a potential dark side – it will be able to crack most of the cryptography on which our cybersecurity is built on the fly. But there are already efforts to establish standards for post-quantum cryptography that will make its use secure and enable its users to maximize the potential of the qubits that will power quantum computing forever—until the next… quantum leap it dare overtake it.