Quantum Computing Explained Simply

Quantum Computing is considered an application of the Quantum mechanics. Which in turn is a branch of modern physics. That branch describes energy and matter at their most fundamental level, that of energy quanta, elementary particles, and quantum fields. It encompasses any discipline concerned with systems that exhibit notable quantum-mechanical effects, where waves have properties…

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October 12, 2023

computing, mechanics, quantum

Quantum Computing is considered an application of the Quantum mechanics. Which in turn is a branch of modern physics. That branch describes energy and matter at their most fundamental level, that of energy quanta, elementary particles, and quantum fields. It encompasses any discipline concerned with systems that exhibit notable quantum-mechanical effects, where waves have properties of particles, and particles behave like waves.

The applications of quantum mechanics are vast and varied. They include explaining phenomena found in nature as well as developing technologies that rely upon quantum effects. Some of the most important applications of quantum mechanics include:

Quantum computing: Quantum computers use quantum bits (qubits) to perform calculations that would be impossible for classical computers. They have the potential to revolutionize computing by solving problems that are currently intractable.
Quantum cryptography: Quantum cryptography uses the principles of quantum mechanics to create secure communication channels. It is based on the fact that any attempt to measure a quantum system will disturb it, making it impossible for an eavesdropper to intercept a message without being detected 1.
Quantum metrology: Quantum metrology uses the principles of quantum mechanics to make extremely precise measurements. It has applications in fields such as timekeeping, navigation, and geodesy 1.
Quantum simulation: Quantum simulation uses quantum computers to simulate complex systems that are difficult or impossible to simulate using classical computers. It has applications in fields such as materials science, drug discovery, and finance 1.
Quantum sensing: Quantum sensing uses the principles of quantum mechanics to make extremely precise measurements of physical quantities such as magnetic fields, electric fields, and temperature. It has applications in fields such as medical imaging, mineral exploration, and environmental monitoring 1.

Other applications of quantum mechanics include explaining phenomena found in nature such as superconductivity and super fluidity, and developing technologies such as integrated circuits and lasers 1.

Quantum mechanics also provides a useful description of nature at the atomic and subatomic scale, but it also manifests itself in phenomena at macroscopic scales, including lasers, clouds of ultra-cold atoms, super fluids, and superconductivity.

What is a quantum computer

A quantum computer is a computer that takes advantage of quantum mechanical phenomena to perform calculations that would be impossible for classical computers 1. At small scales, physical matter exhibits properties of both particles and waves, and quantum computing leverages this behavior, specifically quantum superposition and entanglement, using specialized hardware that supports the preparation and manipulation of quantum states 1. The basic unit of information in quantum computing is the qubit, similar to the bit in traditional digital electronics. Unlike a classical bit, a qubit can exist in a superposition of its two “basis” states, which loosely means that it is in both states simultaneously. When measuring a qubit, the result is a probabilistic/estimated/predicted/assumed output of a classical bit, therefore making quantum computers nondeterministic in general 1.

Quantum computing has the potential to revolutionize computing by solving problems that are currently intractable 1. For example, it could break widely used encryption schemes and aid physicists in performing physical simulations 1. However, the current state of the art is largely experimental and impractical, with several obstacles to useful applications 1. Moreover, scalable quantum computers do not hold promise for many practical tasks, and for many important tasks quantum speedups are proven impossible 1.

Other applications of quantum mechanics include explaining phenomena found in nature such as superconductivity and superfluidity, and developing technologies such as integrated circuits and lasers 1.

How Does a Qubit Work?

A qubit, or quantum bit, is the basic unit of quantum information in quantum computing 1. It is a two-state quantum-mechanical system that can be in a coherent superposition of both states simultaneously 1. In contrast to classical bits, which can only be in one of two possible states (0 or 1), qubits can exist in multiple states at once 1. This property is known as superposition and is fundamental to quantum mechanics and quantum computing 1.

The general definition of a qubit is the quantum state of a two-level quantum system 1. Examples include the spin of an electron, where the two levels can be taken as spin up and spin down, or the polarization of a single photon, where the two states can be taken to be vertical and horizontal polarization 1.

In quantum computing, qubits are used to perform calculations that would be impossible for classical computers. They have the potential to revolutionize computing by solving problems that are currently intractable 1. A qubit uses the quantum mechanical phenomena of superposition to achieve a linear combination of two states 2. It can hold more information than a classical binary bit, e.g., up to two bits using superdense coding 1.

Briefing The Quantum Entanglement Mystery

Quantum entanglement is a phenomenon that occurs when a group of particles are generated, interact, or share spatial proximity in such a way that the quantum state of each particle of the group cannot be described independently of the state of the others, including when the particles are separated by a large distance 1. This means that if two particles are entangled, then measuring the state of one particle will instantaneously affect the state of the other particle, regardless of the distance between them 1.

Entanglement is a fundamental concept in quantum mechanics and is at the heart of many quantum technologies, including quantum computing and quantum cryptography 2. It has been experimentally verified in many different systems, including photons, electrons, and ions 1.

The phenomenon of entanglement is not well understood and has been the subject of much debate and research. It is one of the most puzzling aspects of quantum mechanics and has led to many counterintuitive predictions that have been experimentally verified 1. This adds a point in the next section too.

What Are The Challenges Of Development Under The Quantum Computing

Quantum computing is a rapidly-evolving field that has the potential to revolutionize computing by solving problems that are currently intractable 1. However, there are several challenges that scientists need to overcome before they can use quantum computers for practical purposes.

The following are some of the main challenges in developing quantum computers:

Qubit decoherence:

Qubits are extremely sensitive to their environment, and even small disturbances can cause them to lose their quantum properties, a phenomenon known as decoherence 1. Developing techniques to master decoherence may require new materials, new computational techniques, and deep exploration of various quantum approaches 1.

Scalability:

While quantum computers have shown impressive performance for some tasks, they are still relatively small compared to classical computers 1. Scaling up quantum computers to hundreds or thousands of qubits while maintaining high levels of coherence and low error rates remains a major challenge 1.

Error correction:

Quantum computers are extremely sensitive to noise and errors caused by interactions with their environment 1. Developing reliable error correction techniques is therefore essential for building practical quantum computers 1.

Quantum software development:

Quantum algorithms are much more complex than classical algorithms and require developers to approach computational problems in original ways 1. This complexity has created several challenges for quantum computing scientists, engineers, and entrepreneurs.

Hardware development:

Developing high-quality quantum hardware, such as qubits and control electronics, is a major challenge 1. There are many different qubit technologies, each with its own strengths and weaknesses. Developing a scalable, fault-tolerant qubit technology is a major focus of research 1.

Cost:

Quantum computing is still an emerging technology and is currently expensive to develop and operate 2. The cost of developing quantum hardware and software is high. And the technology is not yet mature enough for scientists to use for practical purposes on a large scale 2.

Education:

Quantum computing requires a deep understanding of quantum mechanics and computer science 2. There is currently a shortage of experts in this field, which could slow down the development of quantum computing technology 2.