The bulk viscosity of two-component fermions with a zero-range interaction is revisited both in two and three dimensions. We first point out that the "standard’’ Kubo formula employed in recent studies has flaws to give rise to an unphysical divergent bulk viscosity even in a limit where it is supposed to vanish. The corrected Kubo formula as well as the sum rule is then carefully rederived so as to confirm that the bulk viscosity indeed vanishes in the free, unitarity, and dimer limits. We also discuss that the recently found discrepancy between the Kubo formalism and the kinetic theory for the bulk viscosity is attributed to the fact that the quasiparticle approximation assumed by the latter breaks down even in the high-temperature limit.

中文翻译：

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重新讨论了共振费米子的体粘度：久保公式，求和规则以及二聚体和高温极限

在二维和三维上都重新讨论了具有零范围相互作用的两组分费米子的体粘度。我们首先指出，最近的研究中使用的“标准”久保公式存在缺陷，即使在应该消失的极限下，也会引起非物理的分散体粘度，然后修正了久保公式和求和规则。仔细地重新进行实验，以确认本体粘度确实在自由度，均匀度和二聚限内消失了；我们还讨论了最近发现的久保形式主义与本体粘度动力学理论之间的差异归因于准颗粒这一事实后者假设的近似值甚至在高温极限下也会分解。