论文标题
在有限温度下的时间依赖格林功能的形式主义中的动力学系数
Kinetic coefficients in the formalism of time-dependent Green's functions at finite temperature
论文作者
论文摘要
我们讨论了模型非依赖性费米和玻色系统中耗散的微观依据，其局部相互作用较弱。在Keldysh -Schwinger框架中考虑了平衡波动的动力学。我们表明耗散与图表技术的捏合奇异性有关。使用dyson -schwinger方程和两循环近似，我们定义并计算与格林功能衰减指数性有关的衰减参数。我们表明，衰减参数是Onsager动力学系数的显微镜类似物，它与激发谱中的衰减有关。
We discuss the microscopical justification of dissipation in the model nonrelativistic Fermi and Bose systems with weak local interactions above phase transitions. The dynamics of equilibrium fluctuations are considered in Keldysh - Schwinger framework. We show that the dissipation is related to pinch singularities of the diagram technique. Using Dyson - Schwinger equation and the two-loop approximation we define and calculate the attenuation parameter which is related to exponentiality of Green's functions decay. We show that the attenuation parameter is the microscopic analogue of the Onsager kinetic coefficient and it is related to attenuation in the excitation spectrum.
