This article is concerned with the time evolution of spin observables for generalized spin boson models. This applies in particular to a model of nuclear magnetic resonance, namely a ##IMG## [http://ej.iop.org/images/1751-8121/53/24/245204/aab8e04ieqn1.gif] {$\frac{1}{2}$} -spin particle in a constant external magnetic field and in interaction with the quantized electromagnetic field (photons). We derive a Lindblad (or GKLS) type approximation of the spin dynamics initially in a photon vacuum state together with a precise control of the error coming from this approximation. The error term is bounded by g 2 where g is the coupling constant of the spin–photon interaction. The point here is the uniformity in time t > 0 of this error control.

中文翻译：

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量子电动力学中的Lindblad逼近和自旋弛豫

本文涉及广义自旋玻色子模型的自旋可观测量的时间演化。这尤其适用于核磁共振模型，即## IMG ## [http://ej.iop.org/images/1751-8121/53/24/245204/aab8e04ieqn1.gif] {$ \ frac {1} {2} $}-在恒定的外部磁场中并与量化的电磁场（光子）相互作用旋转粒子。我们推导了最初在光子真空状态下自旋动力学的Lindblad（或GKLS）类型近似值，以及对该近似值产生的误差的精确控制。误差项以g 2为界，其中g是自旋-光子相互作用的耦合常数。这里的重点是该错误控制的时间t> 0的均匀性。