How random are random numbers generated using photons?

TL;DR

This paper evaluates the randomness of photon-generated bit sequences using Borel normality, confirming their randomness and addressing previous reports of deviations, thereby advancing quantum random number generation analysis.

Contribution

It applies Borel normality to photon-based random sequences, providing a quantitative assessment of their randomness and discussing discrepancies in prior findings.

Findings

Photon sequences fulfill randomness criteria

Borel normality confirms the sequences are random

Addresses previous deviations reported in photon randomness

Abstract

Randomness is fundamental in quantum theory, with many philosophical and practical implications. In this paper we discuss the concept of algorithmic randomness, which provides a quantitative method to assess the Borel normality of a given sequence of numbers, a necessary condition for it to be considered random. We use Borel normality as a tool to investigate the randomness of ten sequences of bits generated from the differences between detection times of photon pairs generated by spontaneous parametric downconversion. These sequences are shown to fulfil the randomness criteria without difficulties. As deviations from Borel normality for photon-generated random number sequences have been reported in previous work, a strategy to understand these diverging findings is outlined.