The computer that both exists and doesn’t holds the key to a hidden Universe16 min readReading Time: 9 minutes
Part 2 of this story is available. Click on the next page at the bottom of this article.
Let’s take a look at what in this massive Universe all of that means.
You’ve probably learned about atoms and molecules in class before. And if you have, you’d instantly think of them as the tiniest, most fundamental building blocks of the Universe. Even all of us humans are made up of billions of atoms stacked together to form molecules which then form cells that make up our organs and so on and so forth.
However, the fact that atoms are the smallest possible units of matter is both true and not true. It all depends on how you look at the world. Classical physics states that atoms are in fact the smallest building blocks of all matter. Quantum physics looks deeper. It looks at the tinier, far more chaotic world of the subatomic particles that make up atoms (think electrons, neutrons and protons). Unlike all the stuff we study about in school, these particles defy the laws of physics and any kind of intuition or common sense.
So while atoms may be the smallest comprehensible building blocks of the universe, subatomic particles are tiny, notorious, gibberish-like particles that chaotically co-ordinate with one another to create the universe as we know it. Imagine subatomic particles as a book of utter gibberish, in which each page means nothing at all. However, all together, all the pages co-ordinate in such a way that the book has a story to tell. It is that story that quantum physicists are working to decipher. But with no laws and no order, the task at hand is more daunting than a mere mortal can imagine.
The computer challenge
But what about a computer? Can a computer understand the chaos of the quantum world fast enough to make sense of it? That’s exactly what one of the world’s most renowned physicists Richard Feynman wanted to know. And he gave it a shot.
Unfortunately, Feynman was unable to unlock the secrets of the universe. It turned out that even computers weren’t cut out for the task at hand. However, he surmised that what he needed was a computing system that worked not according to the laws of physics but rather in tune with the laws of quantum physics.
Quantum computing is a system of computing that works according to the principles of quantum physics rather than classical physics.
How is a quantum computer different?
The word quantum denotes the tiniest possible unit of something. Instead of working with the usual bits of information that computers process, quantum computers work with sub-atomic, chaotic and disorderly bits of digital information known as qubits.
Thanks to their subatomic uniqueness, qubits can store and process far more information than regular bits. And all this processing can be done fast, Extremely fast! You’ll soon see what we mean.
Bits and Qubits
You may feel like you’re in a Marvel loop of science fiction nonsense, but don’t worry, this isn’t some made up Thor science (although it sure seems like it). The quantum world is so complex that even the scientists who study it, don’t fully understand it. Anyhow, here’s a short explanation that should paint a slightly clearer picture of how digital information is stored.
All of the data on the internet, including, but not limited to everything you can search for on Google is stored as digital information. This digital information is stored in units known as bits. (You’ve probably heard the terms MB[megabytes] and GB[gigabytes]. These aren’t just markers for how fast or slow your internet is, but rather they are terms for huge collections of bits.
A collection of 8 bits is known as a byte.
Digital bits store data in computers as patterns of ‘0s’ and ‘1s’ or what is known as binary. Your tweets, your YouTube videos and instagram comments are all strings of ‘0’s and ‘1’s. That’s right your computer groups processes and produces these patterns at extremely high speeds and translates them into the information that you can access on these computers. So, all the data that you enter into your computer is stored as groups of bits. In a normal computer, a bit is the smallest and simplest form of data.
But, as you’ve probably surmised by now, quantum computers are anything but normal. They use quantum bits to store and process data. You’re probably wondering what could be smaller and simpler than a ‘0’ and a ‘1’. Nothing. But, what if something could be both a ‘0’ and a ‘1’ at the same time?
The physicist, Alexander Schrödinger, had once asked people to imagine a box in which a cat exists in a quantum state and ends up being both alive and dead at the same time. This experiment went on to become one of the most famous depictions of the illogical logic of quantum physics.
Yup, like Shrödinger’s dead/alive cat, qubits can be ‘0’, ‘1’, or both at the same time! At this point everything you thought you knew may seem untrue. But don’t you worry, because it is both true and entirely untrue– at the same time!
So, unlike bits, qubits have two special properties. The first of their abilities is to be two polar opposites at once.
This ability is known as superposition. The other superpower of qubits is known as entanglement.
Entanglement is the ability of qubits to co-ordinate with one other to generate information. These two properties allow qubits to store exponentially more information than bits. For instance, 10 qubits can store and process the same amount of information as 16,000 bits!!
A little math:
Thanks to the power of superposition one qubit can store 2 bits. Then, thanks to quantum entanglement two qubits can coordinate to store 2*2 bits or 4 bits. When these two entangled qubits get entangled with a third qubits they can store 2*2*2 or 2^3 qubits. Add another qubit to the entanglement and you can store 2*2*2*2 bits. This pattern can go on forever.
Take a break! You’re not a qubit. You need some time to imbibe this chaos. Come back later to learn all about how computers and qubits could come together to unlock the secrets of the universe.