Barren plateaus in quantum neural network training landscapes

@article{McClean2018BarrenPI,
  title={Barren plateaus in quantum neural network training landscapes},
  author={Jarrod R. McClean and Sergio Boixo and Vadim N. Smelyanskiy and Ryan Babbush and Hartmut Neven},
  journal={Nature Communications},
  year={2018},
  volume={9}
}
Many experimental proposals for noisy intermediate scale quantum devices involve training a parameterized quantum circuit with a classical optimization loop. Such hybrid quantum-classical algorithms are popular for applications in quantum simulation, optimization, and machine learning. Due to its simplicity and hardware efficiency, random circuits are often proposed as initial guesses for exploring the space of quantum states. We show that the exponential dimension of Hilbert space and the… 

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