Computing with quanta—impacts of quantum theory on computation

Umesh V. Vazirani

Alberto Galindo, Miguel Angel Martin-Delgado

Quantum theory has found a new field of application in the realm of information and computation during recent years. This paper reviews how quantum physics allows information coding in classically unexpected and subtle nonlocal ways, as well as information processing with an efficiency largely surpassing that of the present and foreseeable classical computers. Some notable aspects of classical and quantum information theory will be addressed here. Quantum teleportation, dense coding, and quantum cryptography are discussed as examples of the impact of quanta on the transmission of information. Quantum logic gates and quantum algorithms are also discussed as instances of the improvement made possible in information processing by a quantum computer. Finally the authors provide some examples of current experimental realizations for quantum computers and future prospects.

Craig S. Lent

Jonathan Allday, Simon Hands

In quantum theory, and especially quantum field theory, the nature of quantum states is transformed if the particles are identical. In fact, the impact of particles (or better quanta) being identical is more profound in quantum theory than in classical mechanics. Their identity has direct experimental consequences over and above those related to the occupation of states. Over the next couple of chapters, we will explore the quantum theory of identical particles to draw out the impact on the entropy of a collection of such particles .

Tatyana Aleksandrovna Peleshenko, Diana Fedash, Alexandr Gish

Quantum computers are a revolutionary technology based on the principles of quantum mechanics. Unlike conventional computers that work with binary bits (0 or 1), quantum devices use qubits that can exist in multiple states (“superpositions”) and interact with each other through the phenomenon of “quantum entanglement.” Thanks to this, quanta can greatly accelerate the solution of a number of important problems that were previously considered insurmountable for classical machines. This review describes the principles of operation of quantum computers, considers their unique advantages, and demonstrates the potential for their impact on the future of computer science and the technology industry.

Paul M. B. Vitanyi