论文标题
广告中的循环不透明度
Opacity from Loops in AdS
论文作者
论文摘要
我们研究了量子动力学如何影响洛伦兹广告中标量场的传播。我们在动量空间中工作，在该空间中，繁殖器除了封闭形式外，还可以接受两个光谱表示（表示“共形”和“动量”），并且都具有简单的拆分结构。为了关注标量气泡，我们计算了三个表示中的自能量$ {\ rm im}π$的虚构部分，其中涉及对看似非常不同的对象的评估。我们明确地证明了它们在任何维度上的等价性，并得出了$ {\ rm im}π$的某些基本和渐近性能。 在及时的区域中，我们使用类似WKB的方法，评估了带有自我能力的虚构部分的传播器。我们发现，当端点之一位于IR区域中时，回路的敷料会呈指数式抑制传播器，从而使该区域不透明到繁殖。这种抑制可能对广告中的现场理论模型建设有影响。我们认为，在有效的理论（EFT）范式中，高维操作员引起的IR区域的不透明度检查了EFT崩溃的区域。这证实了文献的早期期望。专门针对广告$ _5 $，我们确定对重力不透明度的普遍贡献。
We investigate how quantum dynamics affects the propagation of a scalar field in Lorentzian AdS. We work in momentum space, in which the propagator admits two spectral representations (denoted "conformal" and "momentum") in addition to a closed-form one, and all have a simple split structure. Focusing on scalar bubbles, we compute the imaginary part of the self-energy $ {\rm Im} Π$ in the three representations, which involves the evaluation of seemingly very different objects. We explicitly prove their equivalence in any dimension, and derive some elementary and asymptotic properties of $ {\rm Im} Π$. Using a WKB-like approach in the timelike region, we evaluate the propagator dressed with the imaginary part of the self-energy. We find that the dressing from loops exponentially dampens the propagator when one of the endpoints is in the IR region, rendering this region opaque to propagation. This suppression may have implications for field-theoretical model-building in AdS. We argue that in the effective theory (EFT) paradigm, opacity of the IR region induced by higher dimensional operators censors the region of EFT breakdown. This confirms earlier expectations from the literature. Specializing to AdS$_5$, we determine a universal contribution to opacity from gravity.
