Classical vs. Quantum Computing
A side-by-side comparison, including where quantum offers no advantage.
Quantum Algorithms
What is quantum algorithms?
A quantum algorithm is a procedure that uses quantum operations and interference to solve a problem, often with fewer steps than the best known classical method.
Known examples include Shor's factoring algorithm, Grover's search, and quantum simulation of physical systems.
Speedups are problem-specific: many everyday computational tasks gain nothing from quantum hardware.
Recommended learning sequence
- Classical vs. Quantum ComputingA side-by-side comparison, including where quantum offers no advantage.
- How Does Quantum Computing Work?The prepare–evolve–measure cycle, and why interference is the whole trick.
Frequently asked questions
- How does quantum computing work?
- Qubits are prepared, transformed by gates, and measured, with interference arranged so the useful outcome is likely to appear.
- Can quantum computers replace ordinary computers?
- No. They are specialised accelerators for particular problems.
Lessons in this topic
How Does Quantum Computing Work?
The prepare–evolve–measure cycle, and why interference is the whole trick.
Related subjects
Quantum Gates and Circuits
A quantum gate is a reversible operation on qubits; a quantum circuit is a time-ordered sequence of gates ending in measurement.
Quantum Error Correction
Quantum error correction encodes a logical qubit across many physical qubits so errors can be detected and corrected without reading the stored information.
Quantum Hardware
Quantum hardware comprises the physical systems and control electronics that implement and manipulate qubits.