标题： 随机扰动理论与胶子凝聚态 显示英文标题

标题： Stochastic Perturbation Theory and the Gluon Condensate

摘要： 在晶格上寻找胶子凝聚态是很困难的，因为在寻找可能由胶子凝聚态产生的微小贡献之前，必须从作用量的期望值中减去大的微扰贡献。 因此，微扰计算必须非常精确。 我们使用随机微扰理论的一个修改版本来计算在增强耦合下的微扰级数，该级数比使用通常的晶格耦合的级数收敛得更快，从而减少了我们的结果中的不确定性。 我们没有看到早期一些晶格研究建议的存在二重维度的凝聚态，但我们确实发现了一个四重维度凝聚态的贡献。 这个凝聚态的数值大约是 0.04(1) GeV^4，但有较大的不确定性。 显示英文摘要

摘要： On the lattice searching for the gluon condensate is difficult because a large perturbative contribution to the expectation value of the action has to be subtracted before looking for a small contribution from a possible gluon condensate. The perturbative calculation therefore has to be very precise. We use a modified version of stochastic perturbation theory to calculate a perturbative series in a boosted coupling, which converges more rapidly than the series with the usual lattice coupling, reducing the uncertainties in our results. We do not see any condensate of dimension two, as suggested by some earlier lattice studies, but we do find a contribution from a dimension four condensate. The value of this condensate is approximately 0.04(1) GeV^4, but with large uncertainties.