For quantum integrable systems the currents averaged with respect to a generalized Gibbs ensemble are revisited. An exact formula is known, which we call “collision rate ansatz”.While there is considerable work to confirm this ansatz in various models, our approach uses the symmetry of the current-charge susceptibility matrix, which holds in great generality. Besides some technical assumptions, the main input is the availability of a self-conserved current, i.e. some current which is itself conserved. The collision rate ansatz is then derived. The argument is carried out in detail for the Lieb-Liniger model and the Heisenberg XXZ chain. The Fermi-Hubbard is not covered, since no self-conserved current seems to exist. It is also explained how from the existence of a boost operator a self-conserved current can be deduced.

中文翻译：

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量子可积系统的碰撞率ansatz

对于量子可积系统，将重新讨论关于广义吉布斯系综的平均电流。已知一个精确的公式，我们将其称为“碰撞率ansatz”。尽管在各种模型中都需要进行大量工作来确认该ansatz，但我们的方法使用了电流电荷敏感性矩阵的对称性，该矩阵具有很高的通用性。除了一些技术假设之外，主要输入是自保持电流的可用性，即一些自身保持的电流。然后得出碰撞率ansatz。对Lieb-Liniger模型和Heisenberg XXZ链进行了详细论证。由于似乎不存在自守电流，因此不包括费米-哈伯德。还说明了如何通过存在升压运算符来推导自保持电流。