Shor's algorithm
Shor's algorithm is a quantum algorithm that efficiently factors integers and solves discrete logarithms using quantum period finding.
Quantum Programming in Depth
Shor's algorithm is a quantum algorithm for integer factorization with asymptotically better performance than the best known classical factorization algorithms.
- How it is used
- Frames integer factorization as a candidate application for quantum advantage when the problem has exploitable structure.
- How deep it goes
- Explains the factorization goal, periodicity, asymptotic promise, and practical caveat without deriving the algorithm or implementation.
- Examples
- Uses factoring a single number and finding its divisors as the concrete problem example.
- What you can do after
- Evaluate whether factorization has the structure and scaling needed to justify a quantum approach.
Read how Quantum Programming in Depth explains Shor's algorithm →
Real-World Cryptography
Shor's algorithm is a quantum algorithm that efficiently solves integer factorization and discrete logarithm problems.
- How it is used
- Frames the quantum threat to asymmetric cryptography and motivates migration toward post-quantum cryptography.
- How deep it goes
- Explains period finding and its cryptographic consequences, but stops short of implementation details or a formal proof.
- Examples
- Uses g^x mod N, RSA, Diffie–Hellman, elliptic curves, and long-term health or government records as threat examples.
- What you can do after
- Evaluate which public-key systems are vulnerable to future quantum attacks and why post-quantum migration matters.
Read how Real-World Cryptography explains Shor's algorithm →
Related concepts
- factorizationaddresses · Factorization is the decomposition of a mathematical object, such as an integer or joint distribution, into simpler multiplicative factors.
- discrete logarithmaddresses · A discrete logarithm is an exponent or scalar that relates a specified group element to a base or generator under the group operation.
- periodaddresses · A period is the interval or number of steps between successive repetitions of a function, process, sequence, pattern, or state.
- quantum algorithmkind of · A quantum algorithm is a computational procedure designed to run on a quantum computer and exploit quantum-mechanical states or operations.
- post-quantum cryptographycontrasts with · Post-quantum cryptography is cryptography designed to resist attacks by quantum computers while generally running on conventional computers.
- RSAcontrasts with · RSA is a public-key cryptosystem based on the computational difficulty of factoring large composite integers and supporting encryption and digital signatures.
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