论文标题
宇宙学可观察的长模式的弹性
Resilience of long modes in cosmological observables
论文作者
论文摘要
通过仔细实施涉及长波长模式的量规变换，我们表明，涉及挤压双光谱构型的各种效果，其中一个傅立叶模式比其他两个模式要短得多，但不能被衡量，除非非物理恰好的无限波长（$ k = 0 $）限制。我们的结果尤其适用于单场通货膨胀的Maldacena一致性关系，产生了本地的非高卢强度$ f _ {\ rm nl}^{\ rm local} = - （5/12）（5/12）（N_S-1）$ nl}^{\ rm gr} = -5/3 $术语，出现在暗物质biseptrum和Halo偏置中，这是由于物质扰动的一般相对论非线性进化的结果。因此，通过未来的高敏化实验，从原则上讲，这种影响是物理的，并且可以观察到。
By a careful implementation of gauge transformations involving long-wavelength modes, we show that a variety of effects involving squeezed bispectrum configurations, for which one Fourier mode is much shorter than the other two, cannot be gauged away, except for the unphysical exactly infinite-wavelength ($k=0$) limit. Our result applies, in particular, to the Maldacena consistency relation for single-field inflation, yielding a local non-Gaussianity strength $f_{\rm NL}^{\rm local} = - (5/12)(n_S-1)$ (with $n_S$ the primordial spectral index of scalar perturbations), and to the $f_{\rm NL}^{\rm GR} = -5/3$ term, appearing in the dark matter bispectrum and in the halo bias, as a consequence of the general relativistic non-linear evolution of matter perturbations. Such effects are therefore physical and observable in principle by future high-sensitivity experiments.
