Category: Nodal subroutines

Introduction Quantum error correction is a local subroutine used to protect quantum states against noise, decoherence, and imperfect operations. Unlike classical error correction, it cannot work by directly copying or measuring the protected information. Instead, the quantum state is encoded into a larger Hilbert space so that errors can be detected and corrected without revealing…

Introduction This subroutine uses quantum resources to randomly generate numbers using a Quantum Random Number Generator (QRNG) routine. We write randomness generation instead of  pseudo-random number generation as it is possible to gain `true’ randomness from a QRNG. Generating random number of the one of the most important goals of computer scientist because of its…

Introduction The no-cloning theorem in Quantum Mechanics states that it is impossible to create a perfect copy of arbitrary unknown quantum states. However, imperfect cloning is possible in many different ways. The cloning protocols are either approximate cloning, meaning that at all the rounds they produce approximately similar copies, or they are probabilistic protocols which…

Introduction Classical pseudo-random number generation runs a pseudo-random number generator (PRNG) on a classical machine that pseudo-randomly samples numbers from a space given an input seed. Outline N/A Assumptions The distribution of the numbers output from is sufficiently statistically close to random. Notation No content has been added to this section, yet! Properties No content…

Introduction The quantum SWAP test is a basic quantum subroutine used to compare two quantum states. Given two input states, it checks if they are equal, and it estimates how close they are by measuring an auxiliary control qubit after a controlled-SWAP operation. In quantum protocols, the SWAP test can be used as a local…

Introduction Privacy amplification is a nodal subroutine in which a party, or a set of honest parties, locally compress a partially secret classical string into a shorter string that is secure against an adversary. In quantum protocols, this subroutine usually appears after measurement and classical error correction. At that point, the honest parties may share…

Introduction Classical error correction is a nodal subroutine in which a party processes classical data in order to detect and correct errors. In quantum protocols, this subroutine often appears after a quantum communication or measurement stage, when the relevant quantum information has already been converted into classical strings. The goal is to transform noisy or…

Introduction The Orthogonal Superposition Machine (or the Quantum Adder) is a quantum machine or protocol which allows creating the superposition of two unknown orthogonal states with the desired weights (absolute values of probability amplitudes) beyond the no-superposition theorem. This task can be done with a higher probability of success than the general superposition protocol. It…