Strongly coupled perturbations in two-field inflationary models
Strongly coupled perturbations in two-field inflationary models
复制标题
双场暴胀模型中的强耦合扰动
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
K. Turzyński
中科院分区：
文献类型：
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作者：
S. Cremonini;Z. Lalak;K. Turzyński
我们研究了具有两个标量场和非正则动力学项的暴胀模型，重点研究了曲率和等曲率扰动相互强耦合的情况。在该制度中，一个沉重的模式可以识别和整合出来，我们澄清了从完整的双场模型，一个有效的单场描述的通道。然而，强耦合在系统中设置了一个新的尺度，并影响了扰动的演化以及有效场论有效性制度的开始。特别是，该模型的预测是敏感的耦合和重模式的质量之间的相对层次。其结果是，可观的是不明确地给出一个有效的单场模型的参数与非平凡的声速。最后，在有效理论的有效性范围内发生声视界穿越的要求导致声速的下限。我们的分析是在一个非常简单的玩具模型的慢卷膨胀，这是因为它的易处理性，但不平凡的，足以说明丰富的动力学在非正则多场模型。
We study models of inflation with two scalar fields and non-canonical kinetic terms, focusing on the case in which the curvature and isocurvature perturbations are strongly coupled to each other. In the regime where a heavy mode can be identified and integrated out, we clarify the passage from the full two-field model to an effectively single-field description. However, the strong coupling sets a new scale in the system, and affects the evolution of the perturbations as well as the beginning of the regime of validity of the effective field theory. In particular, the predictions of the model are sensitive to the relative hierarchy between the coupling and the mass of the heavy mode. As a result, observables are not given unambiguously in terms of the parameters of an effectively single field model with non-trivial sound speed. Finally, the requirement that the sound horizon crossing occurs within the regime of validity of the effective theory leads to a lower bound on the sound speed. Our analysis is done in an extremely simple toy model of slow-roll inflation, which is chosen for its tractability, but is non-trivial enough to illustrate the richness of the dynamics in non-canonical multi-field models.
影响因子：
8.7
作者：
Komatsu, E.;Smith, K. M.;Wright, E. L.
通讯作者：
Wright, E. L.