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arXiv 0710.4664hep-th
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用耗散效应面对暴胀宇宙学的跨普朗克问题

Confronting the trans-Planckian question of inflationary cosmology with dissipative effects

Renaud Parentani

摘要:

我们提供了一类QFT表现出高于阈值能量的耗散,从而打破洛伦兹不变性。通过将场耦合到引入静止坐标系的附加自由度(重场)来保持么正性。利用等价原理,我们在任意弯曲的时空中定义了这些理论。然后,我们将面对暴胀宇宙学的跨普朗克问题。当耗散随能量增加时,描述绝热扰动的量子场在暴胀开始时完全阻尼。然而,它仍然作为一个由附加字段组成的复合运算符存在。当它们处于基态时,如果阈值能量比哈勃参数大得多,则得到标准功率谱。事实上,当能量红移低于阈值时,复合算符的行为就好像它是一个被赋予标准真空涨落的自由场。我们的模型之间的关系和膜世界的情况下研究的Libanov和Rubakov显示类似的效果进行了讨论。耗散的签名将在即将发表的论文中进行研究。

英文摘要:

We provide a class of QFTs which exhibit dissipation above a threshold energy, thereby breaking Lorentz invariance. Unitarity is preserved by coupling the fields to additional degrees of freedom (heavy fields) which introduce the rest frame. Using the Equivalence Principle, we define these theories in arbitrary curved spacetime. We then confront the trans-Planckian question of inflationary cosmology. When dissipation increases with the energy, the quantum field describing adiabatic perturbations is completely damped at the onset of inflation. However it still exists as a composite operator made with the additional fields. And when these are in their ground state, the standard power spectrum obtains if the threshold energy is much larger that the Hubble parameter. In fact, as the energy redshifts below the threshold, the composite operator behaves as if it were a free field endowed with standard vacuum fluctuations. The relationship between our models and the Brane World scenarios studied by Libanov and Rubakov displaying similar effects is discussed. The signatures of dissipation will be studied in a forthcoming paper.

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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