# Analyzing the barren plateau phenomenon in training quantum neural network with the ZX-calculus

@article{Zhao2021AnalyzingTB, title={Analyzing the barren plateau phenomenon in training quantum neural network with the ZX-calculus}, author={Chen Zhao and Xiao-Shan Gao}, journal={Quantum}, year={2021}, volume={5}, pages={466} }

In this paper, we propose a general scheme to analyze the gradient vanishing phenomenon, also known as the barren plateau phenomenon, in training quantum neural networks with the ZX-calculus. More precisely, we extend the barren plateaus theorem from unitary 2-design circuits to any parameterized quantum circuits under certain reasonable assumptions. The main technical contribution of this paper is representing certain integrations as ZX-diagrams and computing them with the ZX-calculus. The…

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