Can stochastic quantization evade the sign problem? The relativistic bose gas at finite chemical potential.
Can stochastic quantization evade the sign problem? The relativistic bose gas at finite chemical potential.
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随机量化可以避免符号问题吗？
DOI：
10.1103/physrevlett.102.131601
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发表时间：
2009
影响因子：
8.6
通讯作者：
Aarts G
中科院分区：
文献类型：
--
作者：
Aarts G
对于具有复杂作用量的场论，如有限重子密度下的QCD，由于符号问题，非微扰研究是困难的。我们证明了在有限化学势下的相对论玻色气体存在类似于QCD的符号和“银焰”问题。然后，我们应用随机量子化和复杂的朗之万动力学研究这个理论与非微扰晶格模拟。发现在小的化学势下化学势不相关，在大的化学势下相变为凝聚相。我们表明，符号问题是严重的，但是，我们发现，它没有使用这种方法的负面影响。这为随机量子化在非零密度QCD中的应用开辟了新的前景。
A nonperturbative study of field theories with a complex action, such as QCD at finite baryon density, is difficult due to the sign problem. We show that the relativistic Bose gas at finite chemical potential has a sign and “silver blaze” problem, similar to QCD. We then apply stochastic quantization and complex Langevin dynamics to study this theory with nonperturbative lattice simulations. Independence of chemical potential at small and a transition to a condensed phase at large chemical potential are found. Lattices of size, with, 6, 8, 10, are used. We show that the sign problem is severe, however, we find that it has no negative effect using this approach. This improves the prospects of applying stochastic quantization to QCD at nonzero density.