Non-dissipative hydrodynamics: effective actions versus entropy current
Non-dissipative hydrodynamics: effective actions versus entropy current
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DOI：
10.1007/jhep02(2013)153
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发表时间：
2012-11
影响因子：
5.4
通讯作者：
J. Bhattacharya;Sayantani Bhattacharyya;Mukund Rangamani
中科院分区：
文献类型：
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作者：
J. Bhattacharya;Sayantani Bhattacharyya;Mukund Rangamani
虽然传统的流体力学包含耗散效应是很难从一个行动的原则，但它仍然是可能的，以建立经典的行动时，耗散项被关闭。在这份说明中，我们进行了系统的探索，这样的建设，从一个有效的场论方法，并认为存在的非平凡的二阶非耗散流体动力学涉及纯能量动量传输。我们发现这些流体的特征在于五个二阶传输系数的基础上的有效行动（一个三参数的家庭是外尔不变）。另一方面，由于所有这些流体的流动都是非耗散的，它们必然产生零熵;因此，人们可以使用熵流形式主义来理解它们，熵流形式主义为流体动力学输运提供了很多见解。然而，最一般的应力张量与零熵产生的分析结果给出了一个七参数的非耗散流体动力学家庭（一个四参数的子家庭是外尔不变）。由有效作用量方法导出的非耗散流体是熵流守恒约束下流体动力学的一种特殊情况。我们推测的原因不匹配和潜在的限制，有效的行动方法。
While conventional hydrodynamics incorporating dissipative effects is hard to derive from an action principle, it is nevertheless possible to construct classical actions when the dissipative terms are switched off. In this note we undertake a systematic exploration of such constructions from an effective field theory approach and argue for the existence of non-trivial second order non-dissipative hydrodynamics involving pure energy-momentum transport. We find these fluids to be characterized by five second-order transport coefficients based on the effective action (a three parameter family is Weyl invariant). On the other hand since all flows of such fluids are non-dissipative, they entail zero entropy production; one can therefore understand them using the entropy current formalism which has provided much insight into hydrodynamic transport. An analysis of the most general stress tensor with zero entropy production however turns out to give a seven parameter family of non-dissipative hydrodynamics (a four parameter sub-family being Weyl invariant). The non-dissipative fluids derived from the effective action approach are a special case of the fluid dynamics constrained by conservation of the entropy current. We speculate on the reasons for the mismatch and potential limitations of the effective action approach.