Fast Tests for Probing the Causal
Structure of Quantum Processes
Giulio Chiribella and Swati
Abstract The identification of causal relations is a cornerstone of the scientific
method. Traditional approaches to this task are based on classical statistics. However, such classical approaches do not apply in the quantum domain, where a broader
spectrum of causal relations becomes accessible. New approaches to quantum causal
inference have been developed in recent years, and promising new features have
been discovered. In this paper, we review and partly expand the framework and
results of reference (Chiribella and Ebler, Nat. Commun. 10(1):1472, 2019), which
demonstrated quantum speedups in the identification of various types of causal
relations induced by reversible processes.
Keywords Causal inference · Quantum estimation theory · Indefinite causal
order
1 Introduction
Identifying cause-effect relations is a fundamental problem in science and engineering [1–3]. In its simplest form, the problem can be described as follows: an
G. Chiribella ()
QICI Quantum Information and Computation Initiative, Department of Computer Science,
The University of Hong Kong, Pokfulam, Hong Kong
Department of Computer Science, University of Oxford, Oxford, UK
Perimeter Institute for Theoretical Physics, Waterloo, ON, Canada
HKU Shenzhen Institute of Research and Innovation, Shenzhen, China
e-mail: giulio@cs.hku.hk
Swati
QICI Quantum Information and Computation Initiative, Department of Computer Science,
The University of Hong Kong, Pokfulam, Hong Kong
Institute for Quantum Science and Engineering, Department of Physics, Southern University of
Science and Technology, Shenzhen, China
© Springer Nature Switzerland AG 2021
M. B. Paranjape et al. (eds.), Quantum Theory and Symmetries, CRM Series in
Mathematical Physics, https://doi.org/10.1007/978-3-030-55777-5_58
617
Structure of Quantum Processes
Giulio Chiribella and Swati
Abstract The identification of causal relations is a cornerstone of the scientific
method. Traditional approaches to this task are based on classical statistics. However, such classical approaches do not apply in the quantum domain, where a broader
spectrum of causal relations becomes accessible. New approaches to quantum causal
inference have been developed in recent years, and promising new features have
been discovered. In this paper, we review and partly expand the framework and
results of reference (Chiribella and Ebler, Nat. Commun. 10(1):1472, 2019), which
demonstrated quantum speedups in the identification of various types of causal
relations induced by reversible processes.
Keywords Causal inference · Quantum estimation theory · Indefinite causal
order
1 Introduction
Identifying cause-effect relations is a fundamental problem in science and engineering [1–3]. In its simplest form, the problem can be described as follows: an
G. Chiribella ()
QICI Quantum Information and Computation Initiative, Department of Computer Science,
The University of Hong Kong, Pokfulam, Hong Kong
Department of Computer Science, University of Oxford, Oxford, UK
Perimeter Institute for Theoretical Physics, Waterloo, ON, Canada
HKU Shenzhen Institute of Research and Innovation, Shenzhen, China
e-mail: giulio@cs.hku.hk
Swati
QICI Quantum Information and Computation Initiative, Department of Computer Science,
The University of Hong Kong, Pokfulam, Hong Kong
Institute for Quantum Science and Engineering, Department of Physics, Southern University of
Science and Technology, Shenzhen, China
© Springer Nature Switzerland AG 2021
M. B. Paranjape et al. (eds.), Quantum Theory and Symmetries, CRM Series in
Mathematical Physics, https://doi.org/10.1007/978-3-030-55777-5_58
617