A simple approach towards the sign problem using path optimisation
A simple approach towards the sign problem using path optimisation
复制标题
使用路径优化解决符号问题的简单方法
DOI:
--
复制
发表时间:
2018
影响因子:
5.4
通讯作者:
M. Kroyter
中科院分区:
文献类型:
--
作者:
F. Bursa;M. Kroyter
A bstractWe suggest an approach for simulating theories with a sign problem that relies on optimisation of complex integration contours that are not restricted to lie along Lefschetz thimbles. To that end we consider the toy model of a one-dimensional Bose gas with chemical potential. We identify the main contribution to the sign problem in this case as coming from a nearest neighbour interaction and approximately cancel it by an explicit deformation of the integration contour. We extend the obtained expressions to more general ones, depending on a small set of parameters. We find the optimal values of these parameters on a small lattice and study their range of validity. We also identify precursors for the onset of the sign problem. A fast method of evaluating the Jacobian related to the contour deformation is proposed and its numerical stability is examined. For a particular choice of lattice parameters, we find that our approach increases the lattice size at which the sign problem becomes serious from L ≈ 32 to L ≈ 700. The efficient evaluation of the Jacobian (O(L) for a sweep) results in running times that are of the order of a few minutes on a standard laptop.
DOI:
10.1088/1742-6596/706/2/022004
发表时间:
2015-12
期刊:
Journal of Physics: Conference Series
影响因子:
--
作者:
G. Aarts
通讯作者:
G. Aarts
影响因子:
8.6
作者:
Aarts G
通讯作者:
Aarts G
影响因子:
5
作者:
G. Aarts;E. Seiler;I. Stamatescu
通讯作者:
G. Aarts;E. Seiler;I. Stamatescu