论文标题
量子波动引起的真空衰减
Vacuum Decay Induced by Quantum Fluctuations
论文作者
论文摘要
我们将量子场波动的影响对自耦合标量场的元稳定状态的衰减。我们在半经典描述中考虑了两种田间波动及其潜在影响。第一个是时间导数的波动，是一个自由的大规模标量场操作员，它在有限的时空区域平均。这些波动遵守高斯概率分布。假定有足够大的波动会产生类似于经典初始场速度的效应，这会导致有限区域飞越将元稳定状态与稳定真空状态分开的屏障。在这里，我们找到对衰减率的贡献，该衰减速率与量子隧穿的衰减速率相当，如在intsanton近似中计算而来。该结果与其他作者的结果一致。接下来，我们考虑在自由标量场的时间衍生物中二次的操作员波动的影响。二次操作员还可以在有限的空间和时间上平均。现在，平均操作员的概率分布比指数函数较慢，从而使可能发生很大的波动。我们发现对衰减率的贡献比来自量子隧穿或线性场波动的衰减率要大得多，因此似乎是主要的衰减机制。
We treat the effects of quantum field fluctuations on the decay of a meta-stable state of a self-coupled scalar field. We consider two varieties of field fluctuations and their potential effects in a semiclassical description. The first are the fluctuations of the time derivative a free massive scalar field operator, which has been averaged over finite regions of space and time. These fluctuations obey a Gaussian probability distribution. A sufficiently large fluctuation is assumed to produce an effect analogous to a classical initial field velocity, which can cause a finite region to fly over the barrier separating the meta-stable state from the stable vacuum state. Here we find a contribution to the decay rate which is comparable to the decay rate by quantum tunneling, as computed in an instanton approximation. This result is consistent with those of other authors. We next consider the effects of the fluctuations of operators which are quadratic in the time derivative of the free scalar field. The quadratic operator is also averaged over finite regions of space and of time. Now the probability distribution for the averaged operator falls more slowly than an exponential function, allowing for the possibility of very large fluctuations. We find a contribution to the decay rate which is much larger than those coming from either quantum tunneling or linear field fluctuations, and hence appears to be the dominant decay mechanism.
