"A quantum computer is a computer that exploits quantum mechanical phenomena."
It involves developing algorithms and computing models that utilize the principles of quantum mechanics, potentially offering significant speedups for certain types of computations.
Quantum mechanics: A branch of physics that deals with the behavior of matter and energy at a very small scale.
Superposition: An important concept in quantum mechanics that refers to the idea of a single quantum particle existing in multiple states simultaneously.
Entanglement: A unique property of quantum systems that describes a state in which two or more particles are inextricably linked, resulting in simultaneous changes in their properties despite being separated by arbitrary distances.
The qubit: The fundamental unit of information in quantum computing.
Quantum gates: The basic building blocks of quantum circuits.
Quantum algorithms: The algorithms specifically designed to run on quantum computers that leverage the unique properties of quantum systems to solve problems that are beyond the reach of classical algorithms.
Quantum teleportation: A process by which the state of an unknown quantum particle can be transmitted from one location to another instantaneously.
Quantum cryptography: A subfield of cryptography that leverages the principles of quantum mechanics to provide unbreakable encryption.
Topological quantum computing: A type of quantum computing that uses exotic particles called anyons to store and manipulate qubits.
Quantum machine learning: The application of quantum computing to the field of machine learning that has the potential to revolutionize the entire industry.
Quantum error correction: The set of techniques used to protect quantum information from the effects of noise and decoherence.
Quantum annealing: A type of quantum computing that uses quantum fluctuations to solve optimization problems.
Quantum supremacy: The long-awaited milestone in quantum computing when a quantum computer can perform a task that is impossible for classical computers to perform.
Adiabatic quantum computing: A type of quantum computing that uses the adiabatic theorem from physics to solve optimization problems.
Quantum field theory: A theoretical framework used to describe the behavior of the smallest particles in the universe, including electrons and quarks.
Quantum Annealing: Is used for optimization problems, is a special-purpose quantum computing model intended to allow users to find the optimal state among a large set of possible combinations.
Universal Quantum Computing: Allows more complex and general-purpose computations by using quantum algorithms that are programmed to solve a wide range of problems, running on more sophisticated quantum circuits. Universal quantum computers can operate all conceivable quantum algorithms and compute all relevant functions.
Adiabatic Quantum Computing: Uses the adiabatic theorem to find the ground state of a given physical system that corresponds to the solution to the problem being solved.
Quantum Simulation: Focuses on the efficient computation of quantum physics phenomena, such as molecular dynamics, that cannot be solved using classical computational approaches.
Topological Quantum Computing: Uses topological properties of quantum systems to provide fault-tolerant computation.
One-way Quantum Computing: Uses a specific set of entangled states to effect computation protocols that are irreversible.
Quantum Walk: Is an abstract model of quantum computation that describes a quantum particle moving around a graph and is usually represented as a matrix.
"At small scales, physical matter exhibits properties of both particles and waves, and quantum computing leverages this behavior, specifically quantum superposition and entanglement."
"Classical physics cannot explain the operation of these quantum devices, and a scalable quantum computer could perform some calculations exponentially faster than any modern 'classical' computer."
"A large-scale quantum computer could break widely used encryption schemes and aid physicists in performing physical simulations."
"The current state of the art is largely experimental and impractical, with several obstacles to useful applications."
"For many important tasks, quantum speedups are proven impossible."
"The basic unit of information in quantum computing is the qubit, similar to the bit in traditional digital electronics."
"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 output of a classical bit."
"The design of quantum algorithms involves creating procedures that allow a quantum computer to perform calculations efficiently and quickly."
"If a physical qubit is not sufficiently isolated from its environment, it suffers from quantum decoherence, introducing noise into calculations."
"Two of the most promising technologies are superconductors and ion traps."
"In principle, a non-quantum (classical) computer can solve the same computational problems as a quantum computer, given enough time."
"Quantum advantage comes in the form of time complexity rather than computability, and quantum complexity theory shows that some quantum algorithms for carefully selected tasks require exponentially fewer computational steps than the best known non-quantum algorithms."
"Quantum speedup is not universal or even typical across computational tasks, since basic tasks such as sorting are proven to not allow any asymptotic quantum speedup."
"Claims of quantum supremacy have drawn significant attention to the discipline but are demonstrated on contrived tasks, while near-term practical use cases remain limited."
"Optimism about quantum computing is fueled by a broad range of new theoretical hardware possibilities facilitated by quantum physics."
"The improving understanding of quantum computing limitations counterbalances this optimism."
"The impact of noise and the use of quantum error-correction can undermine low-polynomial speedups."
"The current state of the art is largely experimental and impractical, with several obstacles to useful applications."
"Quantum speedups have been traditionally estimated for noiseless quantum computers, whereas the impact of noise and the use of quantum error-correction can undermine low-polynomial speedups."