Analyzing XOR-Forrelation Through Stochastic Calculus

Author Xinyu Wu

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Xinyu Wu
  • Computer Science Department, Carnegie Mellon University, Pittsburgh, PA, USA


I would like to thank Ryan O'Donnell for many helpful comments on this paper.

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Xinyu Wu. Analyzing XOR-Forrelation Through Stochastic Calculus. In 39th International Symposium on Theoretical Aspects of Computer Science (STACS 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 219, pp. 60:1-60:7, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)


In this note we present a simplified analysis of the quantum and classical complexity of the k-XOR Forrelation problem (introduced in the paper of Girish, Raz and Zhan [Uma Girish et al., 2020]) by a stochastic interpretation of the Forrelation distribution.

Subject Classification

ACM Subject Classification
  • Theory of computation → Quantum complexity theory
  • quantum complexity
  • Brownian motion


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