Only a few decades ago quantum technology was purely a theoretical thing. Something that scientists dreamed of. But now, even though this is still an emerging field of physics and engineering, we are very close to breaking through a great discovery.

Just in October 2019 Google “performed a test computation in just 200 seconds that would have taken the best-known algorithms in the most powerful supercomputers thousands of years to accomplish.”

The effects of quantum computing are promising in various areas because mathematical operations can be done considerably faster than the most powerful supercomputers to date can. This is achieved by relying on the principles of quantum physics.

While this might seem like something arcane or even impossible for some people, quantum-based technology has been in use for a while now. Take MRI machines, for example, which creates images based on the spinning of atoms inside our body.

Or some more common technology, like one that can fit in your hand and could tell you where you are at any given time, GPSs. Global Positioning Systems are based on quantum theory.

Among all the quantum technology, the one that causes more controversy is the quantum computer. Its immense computing power can be used to speed up research in medical fields, test more efficient building materials, have better control over certain processes, create algorithms that solve complex problems.

If you think of some of the listed benefits the impact of quantum computing does not seem all that bad. So, why the controversy? What are the negative effects of quantum computing?

To understand this better we have to first answer one question.

## What is quantum computing?

The fact that there are quantum computers that can already operate 1 trillion times faster than what a supercomputer can, has led people to seriously question the cybersecurity implications of quantum computing.

Traditional computers store data in bits. Based on a binary system in which values are 1 an 0 which can translate to 2 states of information, positive and negative respectively. This binary system in which traditional computing is based is also the reason why Megabytes are composed of 1,024 Kilobytes, instead of just 1000 as the name implies.

Although current computing is not obsolete, the binary system has some limitations when it comes to really long and complex operations. Like the ones in which thousands of variables have an impact.

On the other hand, we have quantum-based computers that use qubits instead of bits. The interesting thing about these qubits is that they do not only represent a 1 or a 0 value, but they can also exist as both values at the same time. This quantum property is called superposition, the ability to be positive and negative at the same time.

One of the ways that a qubit can be created is by using superconductivity to maintain a quantum state of the particle. To achieve this, the superconducting qubits must be kept extremely cold, even colder than the vacuum of space. In fact, an absolute 0 cold, or as close as possible.

This is the lowest limit of temperature according to the laws of thermodynamics. 0° Kelvin is about -273.15 C°. At this temperature, the matter has no heat or vibration remaining in it and it only retains its quantum mechanical properties.

Although interesting, that might not seem like very useful information for the casual observer. The most important piece of information that you need to understand quantum computing is that it leverages the quantum properties of particles to exponentially increase processing power.

For instance, Google’s Sycamore Quantum Computer completed a complex computation in 200 seconds. A calculation that would take even the most powerful supercomputers an estimate of 10,000 years.

Although that calculation does not have any real use outside the world of quantum computing it is still pretty impressive. However, that same capability of solving complex problems becomes a menace when it is faced with mathematical problems that should not be solved.

This is the case with cybersecurity.

Although Cybersecurity is composed of various components, including best practices, encryption is fundamental to maintain information unreadable for unwanted eyes.

Current encryption is based on mathematical formulas that transform this clear data into an encrypted message that is supposed to be secure. This way you can transmit or store information and no one without the proper digital key will be able to access it.

Breaking an encryption key is a mathematically daunting task. To the point of being considered impossible to achieve by today’s computing power.

The most straightforward way to break an encryption code is to try all the possible keys until you get the right one. It would seem simple, but imagine this:

A simple 64 bits encryption has 1,800,000,000,000,000,000 possible combinations. A 128 bits encryption code has more than 300 undecillion possible solutions. Even the world’s fastest supercomputer would take an estimate of a trillion years to find that key.

Up to a certain extent, conventional computers can do this. In July 2002 a group announced that it had uncovered a symmetric 64-bit key. However, it took 300,000 people and more than four and a half years of work to achieve this.

A quantum computing method called Grover’s algorithm, however, speeds up the process, turning that 128-bit key into the quantum-computational equivalent of a 64-bit key. The defense is straightforward, though: Make keys longer. A 256-bit key, for example, has the same security against a quantum attack as a 128-bit key has against a conventional attack.

Under these terms, a quantum computer that can operate trillions of times faster than the fastest supercomputer becomes a game-changer.

Encryption is vital to cybersecurity and privacy, at a personal level, at a corporate level and even at a government level. Although the current most secure encryption methods (256 bits) will not become useless against quantum computing, it’s security will be considerably weakened.

The implications of quantum computing in cybersecurity are tangible and it puts a lot more than just a text message at risk. We can only expect that as this technology evolves, encryption methods will evolve as well.