论文标题
铬磁背景场和QCD地面的旋转凝结
Tachyon condensation in a chromomagnetic background field and the groundstate of QCD
论文作者
论文摘要
我认为SU中的铬磁真空（2）。已知有效的Lagrangian在一个循环近似中的最小值低于零以下，从而导致自发产生的磁场。但是，此最低限度不稳定。有效的动作具有虚构的部分。在过去的几十年中，有很多尝试处理这种情况，这在某个时候并不令人满意。我通过假设在低温下获得冷凝水的速度模式来提出一个新溶液的想法，结果，在HIGGS模型中进行类似的相变。我认为除了速度型外，所有gluon模式都被删除的近似值。对于此模式，我们有一个O（2） - 模型，具有四个维度的四分之一自相互作用。我在哈特里近似中应用CJT（2PI）形式主义。结果，在零温度和低温下，观察到在一定的凝结物和背景场的一定值下的有效作用，没有假想的部分。提高温度，这种最小值变得更浅，在临界温度下，扰动状态变成具有较低有效电位的扰动状态。对称性恢复。物理解释说，不稳定的模式会产生tachyon，直到它们以排斥性的自我交流达到平衡并形成冷凝物为止。讨论了与Mermin-Wagner定理的关系。 }
I consider the chromomagnetic vacuum in SU(2). The effective Lagrangian in one loop approximation is known to have a minimum below zero which results in a spontaneously generated magnetic field. However, this minimum is not stable; the effective action has an imaginary part. Over the past decades, there were many attempts to handle this situation which all were at some point unsatisfactory. I propose an idea for a new solution by assuming that the tachyonic mode, at low temperature, acquires a condensate and, as a result, undergoes a phase transition like in the Higgs model. I consider the approximation where all gluon modes are dropped except for the tachyonic one. For this mode, we have a O(2)-model with quartic self-interaction in two dimensions. I apply the CJT (2PI) formalism in the Hartree approximation. As a result, at zero and low temperatures, a minimum of the effective action at a certain value of the condensate and of the background fields is observed and there is no imaginary part. Raising the temperature, this minimum becomes shallower and at a critical temperature, the perturbative state becomes that with lower effective potential; the symmetry is restored. The physical interpretation says that the unstable mode creates tachyons until these come into equilibrium with their repulsive self-interaction and form a condensate. The relation to the Mermin-Wagner theorem is discussed. }
