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arXiv · 2406.03381

Paths towards time evolution with larger neural-network quantum states

Abstract

In recent years, the neural-network quantum states method has been investigated to study the ground state and the time evolution of many-body quantum systems. Here we expand on the investigation and consider a quantum quench from the paramagnetic to the anti-ferromagnetic phase in the tilted Ising model. We use two types of neural networks, a restricted Boltzmann machine and a feed-forward neural network. We show that for both types of networks, the projected time-dependent variational Monte Carlo (p-tVMC) method performs better than the non-projected approach. We further demonstrate that one can use K-FAC or minSR in conjunction with p-tVMC to reduce the computational complexity of the stochastic reconfiguration approach, thus allowing the use of these techniques for neural networks with more parameters.

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Wenxuan Zhang, Bo Xing, Xiansong Xu, Dario Poletti. 2024-06-05. Paths towards time evolution with larger neural-network quantum states. https://arxiv.org/abs/2406.03381

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