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arXiv · 2005.04645

Tensor renormalization group approach to four-dimensional complex $\phi^4$ theory at finite density

Shinichiro Akiyama·Daisuke Kadoh·Yoshinobu Kuramashi·Takumi Yamashita·Yusuke Yoshimura
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Abstract

Tensor network is an attractive approach to field theory with negative sign problem. The complex $\phi^4$ theory at finite density is a test bed for numerical algorithms to verify their effectiveness. The model shows a characteristic feature called the Silver Blaze phenomenon associated with the sign problem in the large volume limit at low temperature. We analyze the four-dimensional model employing the anisotropic tensor renormalization group algorithm. We find a clear signal of the Silver Blaze phenomenon on a large volume of $V=1024^4$, which implies that the tensor network approach is effective even for four-dimensional field theory beyond two dimensions.

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Shinichiro Akiyama, Daisuke Kadoh, Yoshinobu Kuramashi, Takumi Yamashita, Yusuke Yoshimura. 2020-05-10. Tensor renormalization group approach to four-dimensional complex $\phi^4$ theory at finite density. https://doi.org/10.1007/jhep09(2020)177

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