Department of Physics, University of California, Davis, California 95616, USA.
Phys Rev Lett. 2011 Jul 8;107(2):021303. doi: 10.1103/PhysRevLett.107.021303. Epub 2011 Jul 6.
We show that vacuum fluctuations of the stress-energy tensor in two-dimensional dilaton gravity lead to a sharp focusing of light cones near the Planck scale, effectively breaking space up into a large number of causally disconnected regions. This phenomenon, called "asymptotic silence" when it occurs in cosmology, might help explain several puzzling features of quantum gravity, including evidence of spontaneous dimensional reduction at short distances. While our analysis focuses on a simplified two-dimensional model, we argue that the qualitative features should still be present in four dimensions.
我们表明，二维膨胀子引力中的应力-能量张量的真空涨落会导致光锥在普朗克尺度附近的急剧聚焦，有效地将空间分割成许多因果上不连通的区域。这种现象在宇宙学中称为“渐近沉默”，它可能有助于解释量子引力的几个令人困惑的特征，包括短距离下自发维度降低的证据。虽然我们的分析集中在一个简化的二维模型上，但我们认为在四维空间中仍然应该存在定性特征。
