Dodelson Scott, Hui Lam
NASA/Fermilab Astrophysics Center, Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
Phys Rev Lett. 2003 Sep 26;91(13):131301. doi: 10.1103/PhysRevLett.91.131301. Epub 2003 Sep 22.
We demonstrate that the gravity wave background amplitude implies a robust upper bound on the wavelength-to-horizon ratio at the end of inflation: lambda/H(-1) less than or approximately equal e(60), as long as the cosmic energy density does not drop faster than radiation subsequent to inflation. This limit implies that N, the number of e-folds between horizon exit and the end of inflation for wave modes of interest, is less, similar 60 plus a model-dependent factor-for vast classes of slow-roll models, N less than or approximately equal 67. As an example, this bound solidifies the tension between observations of the cosmic microwave background anisotropies and chaotic inflation with a phi(4) potential by closing the escape hatch of large N (<62).
我们证明，只要暴胀之后宇宙能量密度下降速度不超过辐射，引力波背景振幅就意味着暴胀结束时波长与视界之比存在一个稳健的上限：λ/H⁻¹ 小于或近似等于 e⁶⁰。这个限制意味着，对于感兴趣的波动模式，视界穿越与暴胀结束之间的 e 折叠数 N 较小，约为 60 加上一个与模型有关的因子——对于大量慢滚模型，N 小于或近似等于 67。例如，通过关闭大 N（<62）这个逃逸口，这个界限强化了宇宙微波背景各向异性观测与具有 φ⁴ 势的混沌暴胀之间的矛盾。
