Today we’ll talk bout the battle between Blockchain VS Quantum Computers. What exactly are quantum computers and how will it affect the future of Blockchain? Let’s first give a quick review on Blockchain and introduce Quantum Computers.
Since 2017, Blockchain and Cryptocurrencies popularity exploded. There are a lot more investors and developers interested in these technologies. New currencies have been created, some were just a scam, but others are actually trying to stay in the market. Also, new ways of using the potential of Blockchain are being developed every day.
There is no doubt that Blockchain will soon revolutionize the world as we know it. Payments, energy and IoT, are just some of the industries this fantastic technology will impact by bringing security, cheaper fees and faster connections.
If you want to know more about Blockchain, click here: What is blockchain technology?
Quantum mechanics is a branch of science, it’s a branch of physics. It’s the study of things that are really, really small, isolated or cold and this branch of science is what some experts are using to redesign how computing works by building new computers based on the laws of quantum mechanics.
Some of the principles used to build these quantum computers are Superposition, Entanglement and Interference.
What are these properties? What do they do?
So in computer science, a bit can be either a 1 or a 0 right? But with superposition in can be “either one” or “both”. You can also imagine a coin, it’s either heads or tails, but try to say wich one is wille the coin is spinning. Not easy, right? You might also have heard of the “Schrodinger’s cat” story. That is another example of Superposition.
Entanglement is a property that connects two “particles”. When connected, if one of these particles changes its state, so does the other. In the quantum world, it’s very hard to untangle what’s entangled.
Interference can be constructive or destructive. Constructive Interference adds wave amplitudes that add to the signal, and with destructive interference the amplitudes cancel.
But we’ll talk more about quantum computers details on a future post.
So what can these sci-fy computers do more than the regular computers?
Quantum computing creates new possibilities and new ways to approach problems that classical computers can’t. Roughly saying, It’s a really fast really smart computer.
What does this have to do with blockchain?
A blockchain is a mathematical structure that stores and secures data, and it can store any type of data. However, the security of a blockchain is guaranteed by standard cryptographic functions. These functions are very secure and breaking them would require gigantic super computing resources.
That’s where the quantum computers come in. It will be child’s play for quantum computers to break this kind cryptographic protection.
So is Blockchain doomed?
If these computers will be able to easily break blockchain, why are we still trying to implement it?
Because Quantum Computers will not only be able to “break” Blockchain, they will be able to recreate it, making it even stronger, so strong that a quantum computer will not be able to break it. By adding quantum cryptography to Blockchains, a new level of security will be added to the Blockchains.
But according to Del Rajan and Matt Visser at the Victoria University of Wellington in New Zealand, there is an even better solution, by making the entire Blockchain a quantum phenomenon.
By recreatring Blockchain using quantum particles that are entangled in time, allowing a single quantum particle to encode the history of all its predecessors in a way that cannot be hacked without destroying it. A protocol like this relies on the laws of physics to guarantee security, but it also leads to somebody unusual side effects.
“This decentralized quantum blockchain can be viewed as a quantum networked time machine,” say Rajan and Visser.
Security is assured because is that entanglement is very fragile. If a user attempts to interfere with one of the entangled particles, the other particle will also change making it is immediately obvious to others.
But particles can also become entangled over time! This means that an existing particle can be entangled with one that existed in the past. So in a way there is a quantum state in which it becomes possible to influence the past. But don’t worry, it won’t be enough to trigger a butterfly effect or anything like that, this kind of paradox is not possible (we think).
Rajan and Visser tried to exploit this type of temporal entanglement to produce a quantum Blockchain. The idea is to encode data on a quantum particle becoming the first quantum block.
After the first block is created, the second block is created by combining new data with the first block and so on.
This chain is secure because anybody attempting to mess with it immediately invalidates it. That’s the big advantage of quantum entanglement.
Also, quantum Blockchain has yet another advantage: the earlier blocks are impossible do hack.
“The attacker cannot even attempt to access the previous photons since they no longer exist,”
“Entanglement in time provides a far greater security benefit than an entanglement in space.” say Rajan and Visser.
Does all this sound like science fiction to you? But actually, we already have the technology to make this work!
Quantum computers are already being developed. IBM has a 50-qubit quantum computer, but to solve problems like search and factoring algorithms would require millions of error-corrected qubits.
There is also missing a key part for this to work; a quantum web. A network capable of transmitting quantum information via quantum routers without destroying them.
Basically, we are still very early in the quantum computing world, but progress is being made and it’s amazing to think what we can achieve.
Regular Blockchain still is and will continue to be very reliable for a few more decades, and when recreated by quantum computers, nothing will be able to break it.
(As far as we can tell)