Are we ready for the Quantum Apocalypse?

Abinesh B
Abinesh B
Nov 3 · 8 min read

Introduction

We might have heard about apocalypses like zombie apocalypse, alien invasion, natural disasters, and even data apocalypse. But what is this quantum apocalypse?

This is a technical blog about the impact of quantum physics on a computer.

Conventional Computer vs Quantum Computer

The standard/binary computers like the one we use on our homes, offices understand 0s and 1s. We can represent the information in the form of bits. It follows classical physics. The transistors are used in the computer, which can act as a switch. The switch on and off indicates the value of 0 and 1.

The quantum computer, on the other hand follows quantum physics or quantum mechanics. It uses qubits to store and represent the information. The qubit is different from normal bit as the bits can be in either 0 or 1 state but the qubits can be in more than one state at the same time. The principle of superposition and entanglement of quantum mechanics made the qubit possible.

Bit vs Qubit

Why should we go for Quantum Computer?

The normal computer works well for the smaller tasks and their computation time doesn’t matter in these types of tasks. But it cannot go beyond some extent. Quantum computers can do a job in minutes while the normal computers take 100,000 years to complete the same job. This is because of the quantum bit understanding.

Quantum Superposition and Entanglement

When we talk about any macroscopic objects on the earth, we follow classical physics. For Example: when i throw a ball up, it eventually comes back to me after reaching certain height with respect to the force i have given and comes back due to gravity. But when you talk about the behaviour of any microscopic particles like atoms, electrons, photons we follow quantum physics. Quantum computer operates by controlling the behaviour of these particles.

The Superposition Principle

When we take a microscopic particle like an atom , there exists subatomic particles. Inside an atom, there is a nucleus and all the subatomic particles like protons, electrons, and neutrons revolve around the nucleus. Normally, the electrons on the outer orbits are always available to share bonds with another atom. The electrons move faster than the light. As per quantum physics, no material particles can travel faster than light, but subatomic particles can do because of the size and weight of the particles.

So when you talk about an electron revolving around the nucleus, since it travels faster than light, it can literally exist in all possible states around the nucleus. Until it is measured, you cannot predict the state of an electron. This is called superposition. When a particle can exist in more than one state at a time, it follows the superposition principle. Schrödinger explained this concept with a cat to understand the superposition.

In layman's terms, when you flip a coin, you will get heads or tails as a result. That is classical physics. When the coin is in the air, it exists in the mixture state of both heads and tails.That is at that state, the outcome is 50% heads and 50% tails.This state of existing in more than one state is considered as superposition state. When we talk about the superposition state of any quantum particles, that is called quantum superposition.

The Entanglement

The principle of quantum entanglement describes that when the two quantum particles are generated together and supply some amount of energy through them, then the one quantum particle measurement can affect the another quantum particle even it is separated by a very large distance. Since the communication between quantum particles travels 10,000 faster than the light and even more.

When two or more qubits are combined in any circuit, the measurement of one qubit always affects the measurement of another qubit. When you built two qubits together and pass inputs through it, the result will always dependent on each other but with the probability of existing in all possible states.

Entanglement

For example, it is possible to prepare two particles in a single quantum state such that when one is observed to be spin-up, the other one will always be observed to be spin-down and vice versa, this despite the fact that it is impossible to predict, according to quantum mechanics, which set of measurements will be observed.

As a result, measurements performed on one system seem to be instantaneously influencing other systems entangled with it.

The Comic Series Connectivity — Flash and Quantum Tunnelling

You can skip this part if you want. If you have seen Flash Series, you must know that Flash can penetrate through any substance. That is achieved through Quantum tunneling. How is that possible? The Flash vibrates at a frequency making the molecules of his body to attain a superposition state.This means the atoms can exist in different state at the same time. So he can able to penetrate through any substance i.e., altering the states of the body molecules to exists in different places. But in reality that is not possible yet.

How does Quantum mechanics helps computers?

A regular computer will try to solve a problem by solving a maze. It tries a possibility at a time and observes the result and tries another possibility when it is a dead end.It tries every possibility one by one. That is how the information can be represented in binary computers. The superposition principle allows the quantum computer to try all the paths at once, i.e. finding the shortcut.

Two bits in your computer can be in four possible states (00,01,10,11) but only one of them at a time.This limits the computer to processing one input at a time (trying to escape a maze).

In a quantum computer, two qubits can also represent the exact same four states. The difference is, because the superposition, the qubits can represent all four states(00,01,10,11) at the same time. That is like four regular computers running side-by-side.

If the input bits size increases, the normal computer still deal with one state at a time. But when you add more qubits, the power of a quantum computer grows exponentially. For mathematical representation, when you add n qubits together, you can represent 2^n bits simultaneously.

This is how quantum computers can do a job in a minute that the normal computers would take 100s of years to compute.

Source: Facebook

The quantum computing cannot be built anywhere. We should maintain an environment for the qubits to attain the superposition state. The qubits should be maintained at a specific temperature above absolute zero. Due to this computation power, the tech giants like Google, IBM are already investing heavily on building a quantum computer.

The Quantum apocalypse

We make lots of transaction everyday and we enter or store many confidential information on the cloud because we know those information communicated to the respected destination is with proper security with the help of key exchange mechanisms, the SSL certificates of tech giants. But do you think those encryption mechanisms are unbreakable? No. All the cryptographic techniques we use now such as RSA,ECC to store/send confidential informations, all our transactions using blockchain are breakable. But the thing is it could take years to break such strong encryption algorithms with our standard computers.

But what happens if quantum computers try to break the encryption algorithms? Eventually it would take seconds or minutes to break them. Any transaction you make can be viewed by anyone.Any personal information you stored in any cloud could be compromised with the help of quantum computers. This means anyone who has the power of quantum computer can eventually break the internet. No Tech Companies can be able to hide from quantum computers. All the informations will be made public after compromising. This is the quantum apocalypse that we may witness in the near future.

The only way to compete against the quantum apocalypse is the quantum. Fighting the quantum with quantum. The Quantum cryptography is the encryption algorithms developed by the laws of quantum physics. The researches are already in the works to deploy the quantum encryption techniques. But in reality the quantum computers are not yet in practice. IBM has already developed a quantum computer. They have deployed the computing power in cloud and that is accessible for the public. You can try that here https://quantum-computing.ibm.com/ . Try compute the basic quantum circuit and observe the possibility of all the states in the histogram.

IBM Q

Recently Google also claimed that they have achieved the quantum supremacy. The reality of quantum computers will be true after some years. And our world will experience the power of quantum physics.

Other Applications of Quantum Mechanics

  • Quantum Teleportation: If a small atom can exist in a superposition state. Every other object can also exist in the superposition state under the specific environment. The information can be transmitted from one place to another place without even physically transmitting the information. It is possible. The properties of quantum particles gets entangled over time and space. So any change in one particle affects another particle even at larger distance. This creates a channel for teleportation.
  • Medical Research: The design and analysis of molecules for drug development is a challenging problem today. Because exactly describing and designing the atoms of a molecule is difficult task even for supercomputers. But quantum computers could do better because it uses the same quantum particles to design the molecules for drug development. It could perhaps lead us to create medicines for more deadly diseases.
  • Quantum Cryptography: The Quantum uncertainty can be used to create private keys for encrypting the messages. So that the hackers cannot use the original key due to the superposition. The key can exists in different state at the same time.

There will be an article in the upcoming week about the mathematics behind the qubits state representation and how we can interpret results from the qubits. Stay tuned!

Thank You.

Abinesh B

Written by

Abinesh B

NLP Engineer and an Inquisitive Person

Welcome to a place where words matter. On Medium, smart voices and original ideas take center stage - with no ads in sight. Watch
Follow all the topics you care about, and we’ll deliver the best stories for you to your homepage and inbox. Explore
Get unlimited access to the best stories on Medium — and support writers while you’re at it. Just $5/month. Upgrade