The Quantum Leap!
Journey into the Future of Computing…
Before we dive into details it’s worth to clear out couple of terminologies.
- Matter –
Matterrefers to the substance that makes up physical objects & has mass. It encompasses all the materials and substances that we encounter in our everyday lives, such assolids,liquids, andgases. - Particles –
Particlesare the basic constituents of matter. They can be elementary particles likeelectrons,quarks, andneutrinos, or composite particles likeprotonsandneutrons, which are made up of smaller particles calledquarks.
Based on the physics principles that govern the behaviour and properties, there are two broad categories of particles – Classical particles and Quantum particles.
- Classical particle or Classical Objects – These follow classical physics principles and exhibit behaviours consistent with our everyday experiences. They have well-defined
positions,velocities, andproperties, and their motion is described by classical mechanics, which includes Newton’s laws of motion.
A car is a
classical objectthat operates according to classical mechanics. Its motion, such as acceleration, braking, and turning, can be described using classical physics principles. The laws of motion formulated by Newton are sufficient to explain its behavior.
- Quantum particles –
Quantum particles, on the other hand, exhibit quantum behaviours and are described by quantum mechanics. They possess unique properties likesuperpositionandwave-particle duality, and their behaviour cannot be fully explained using classical physics principles.
An example of a quantum particle is the
photon, which is the smallest indivisible unit of light or electromagnetic radiation. Photons behave both as particles and waves, exhibiting the characteristics of quantum particles. In quantum physics, the energy of a photon is quantised, meaning it can only exist in specific discrete amounts called quanta. The energy of a photon is directly proportional to its frequency — higher frequency photons have higher energy, while lower frequency photons have lower energy.
Now with this context, lets try to understand what does Quantum mechanics had to offer in the world of computing.
What is Quantum computing?
Quantum computing is an emerging field of technology that harnesses the principles of quantum mechanics to process & store information. It aims to utilise the unique properties of quantum systems, such as superposition and entanglement, to perform computational tasks more efficiently than classical computers.
Quantum computing has the potential to revolutionise fields such as cryptography, optimisation, simulation of quantum systems, and drug discovery. It offers the possibility of solving complex problems that are currently infeasible or time-consuming for classical computers.
Is Quantum computing worth the hype?
Allow me to illustrate the significance of this hype through two real-world examples that highlight its potential for complete disruption.
Cryptography
In today’s world, RSA encryption finds extensive use in a wide array of applications and systems necessitating secure communication and data encryption. It is employed in secure email communication protocols, TLS/SSL secure web communication, VPN technologies, and more.
The ramifications of an RSA encryption algorithm breach would be significant, potentially crippling institutions and businesses worldwide!
But how would that be even remotely possible?The security of RSA relies on the challenge of factoring large numbers into their prime factors, which is computationally arduous for classical computers.
However, a powerful quantum computer could efficiently factorise large numbers, jeopardising the security of RSA encryption.
As a result, Quantum mechanics enables an alternative development of secure communication systems based on quantum key distribution. It utilises the principle of entanglement to ensure secure transmission of information.
Communication
The existing traditional communication methods, such as sending information over electrical or optical signals, can be vulnerable to eavesdropping and unauthorised interception!
Quantum communication protocols address these security concerns by exploiting the unique properties of quantum systems.
Quantum teleportation, for example, is a protocol that allows the transfer of quantum information from one location to another without physically transporting the quantum state itself. It relies on the phenomenon of quantum entanglement, where two particles become intricately linked regardless of the distance between them. Through quantum teleportation, the quantum state of a particle, known as the “qubit,” can be transmitted to a distant location by utilising an entangled pair of particles. The original qubit is “teleported” to the remote location instantaneously, preserving its quantum properties. Importantly, the act of measuring the qubit destroys the original quantum state, ensuring the security of the transmission.
How Quantum Computers are different from Classical Computers?
Imagine you have two coins, one in your left hand and one in your right hand. In classical physics, each coin can be either heads or tails. So if you flip both coins at the same time, you would get a specific combination of outcomes like heads-heads, heads-tails, tails-heads, or tails-tails.
Classical computers follow a similar approach using bits to store and process information, which can be either a 0 or a 1.
Now, let’s bring in the principles of quantum mechanics. Instead of normal coins, we have special quantum coins. These quantum coins can be in a superposition, meaning they can be in multiple states simultaneously. So when you flip a quantum coin, it’s not just heads or tails — it’s in a fuzzy state of being both heads and tails at the same time. This means that instead of the four specific combinations we had before, we now have all possible combinations happening at once. So we would have heads-heads, heads-tails, tails-heads, and tails-tails, all happening simultaneously.
Superposition
The superposition constitutes the fundamental premise on which Quantum computers are based upon and hence uses quantum bits, or qubits where there could a lot more possible combinations in contrast to existing classical computers. This gives quantum computers a lot of computational power. It’s like having many classical computers working on different parts of a problem all at once.
Entanglement
Another important property of qubits is entanglement. When qubits are entangled, the state of one qubit becomes connected to the state of another qubit, no matter how far apart they are. This means that when you manipulate one qubit, it can instantly affect the state of another qubit, which enables quantum computers to perform complex calculations in parallel.
Quantum computers use algorithms specifically designed to harness the power of superposition and entanglement to solve certain types of problems much faster than classical computers.
Motivation behind Quantum Computing
To comprehend the motivation behind the creation of qubits and the need for quantum computers, let’s start by understanding the concept of a traditional bit in today’s computers.
In the digital realm, a bit serves as the fundamental unit of information. The term “bit” is derived from “Binary Digit,” and it represents the basic unit that can store a binary value. Binary values, as we know, consist of only 1s and 0s.
You may have come across the terms “32-bit” or “64-bit” processor when referring to computers. But what do these designations mean? A 32-bit processor implies that the processor is capable of working with 32-bit binary numbers simultaneously. Although modern computers seem to perform routine tasks quickly (such as web browsing, movie streaming, and gaming), they struggle when it comes to computing highly complex problems.
Consider the scenario where you need to simulate the behaviour of a protein molecule in water for just one second. While this may seem like a relatively small problem, even with modern computers and efficient algorithms, it would take months to compute the results. That’s how slow our computers are in tackling complex problems. Even supercomputers, equipped with numerous parallel processors, face sluggishness when confronted with larger and more intricate problems.
Why are computers sluggish and time-consuming in solving complex problems? It’s because each bit is engaged in one process at a time. Once a process is completed, that same bit will hold information for another process. Even if parallel programming is employed, multiple processors are utilised, but each physical bit in the processor is not shared. All bits within those processors remain separate.
Now, let’s delve into the concept of qubits. A qubit, short for quantum bit, can hold both 1 and 0 simultaneously. This is known as the superposition state, a fundamental characteristic of the quantum world. While a traditional bit can only hold either 0 or 1 at a given time, a qubit has the ability to hold both values simultaneously. Theoretically, a single qubit can participate in millions of processes simultaneously, rendering quantum computers exceptionally fast for certain types of complex operations.
Parting Thoughts
The field of quantum computing is still in its early stages, and researchers are actively working on developing more powerful and reliable quantum hardware, improving error correction techniques, and exploring new quantum algorithms. The ultimate goal is to harness the unique properties of quantum mechanics to solve complex problems that are currently intractable for classical computers, leading to significant advancements in fields like cryptography, optimisation, and drug discovery.
