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arXiv 1104.0244astro-ph.COhep-th
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非真空初态慢卷暴胀定域型fNL的计算

Calculating the local-type fNL for slow-roll inflation with a non-vacuum initial state

Jonathan Ganc

备注：
8 pages, 1 figure. v2: Version accepted for publication in PRD. Added greatly expanded discussion of the phase angle θ_k; this allows the possibility of enhanced fNL, as mentioned in abstract. More explicit comparisons with earlier work
发表信息：
Phys. Rev. D 84, 063514 (2011)
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摘要：

具有非真空初态的单场慢卷暴胀在局域极限处具有增强的双谱。我们数值计算了CMB中的局部型fNL信号，该信号将针对此类模型进行测量（包括完整的传递函数和2D投影）。结果的性质取决于几个参数，包括占有数N_k、Bogoliubov参数之间的相位角θ_k和慢滚参数ε。在最保守的情况下，取θ_PDMATHABMM η_0 k（由本文讨论的物理原因证明）和ε \lesssim 0.01，我们发现0 < fNL < 1.52（ε/0.01），这可能太小而无法在CMB中检测到。然而，如果人们愿意允许相位角θ_k为一个恒定值并且N_k=O（1），fNL可以大得多和/或为负（取决于θ_k的选择），例如fNL \approx 28（ε/0.01）或-6.4（ε/0.01）;取决于ε，这些情况可以被普朗克或未来的卫星探测到。虽然我们表明，这些结果实际上并没有违反单场一致性关系，但它们确实产生了fNL的值，该值远远大于通常从单场暴胀预测的值。

英文摘要：

Single-field slow-roll inflation with a non-vacuum initial state has an enhanced bispectrum in the local limit. We numerically calculate the local-type fNL signal in the CMB that would be measured for such models (including the full transfer function and 2D projection). The nature of the result depends on several parameters, including the occupation number N_k, the phase angle θ_k between the Bogoliubov parameters, and the slow-roll parameter ε. In the most conservative case, where one takes θ_k \approx η_0 k (justified by physical reasons discussed within) and ε\lesssim 0.01, we find that 0 < fNL < 1.52 (ε/0.01), which is likely too small to be detected in the CMB. However, if one is willing to allow a constant value for the phase angle θ_k and N_k=O(1), fNL can be much larger and/or negative (depending on the choice of θ_k), e.g. fNL \approx 28 (ε/0.01) or -6.4 (ε/0.01); depending on ε, these scenarios could be detected by Planck or a future satellite. While we show that these results are not actually a violation of the single-field consistency relation, they do produce a value for fNL that is considerably larger than that usually predicted from single-field inflation.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

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