arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1003.5751astro-ph.COgr-qchep-th
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暗能量尘埃

Dust of Dark Energy

Eugene A. Lim, Ignacy Sawicki, Alexander Vikman

摘要:

我们引入一类新的场论,其中能量总是沿着类时测地线流动,在这方面模仿尘埃,但具有非零压力。该理论包括两个标量场,其中一个是拉格朗日乘子,在另一个的场值和导数之间强制执行约束。我们表明,该系统不具有波动模式,但保留了一个单一的动力学自由度。因此,声速在所有背景下始终为零。特别是,宇宙学扰动再现了声速消失的流体力学的标准行为。利用所有这些性质,我们提出了一个模型统一暗物质和暗能量在一个单一的自由度。在一定的限制下,该模型准确地再现了Lambda-CDM的演化历史,而偏离标准膨胀历史产生了潜在的可测量的结构演化差异。

英文摘要:

We introduce a novel class of field theories where energy always flows along timelike geodesics, mimicking in that respect dust, yet which possess non-zero pressure. This theory comprises two scalar fields, one of which is a Lagrange multiplier enforcing a constraint between the other's field value and derivative. We show that this system possesses no wave-like modes but retains a single dynamical degree of freedom. Thus, the sound speed is always identically zero on all backgrounds. In particular, cosmological perturbations reproduce the standard behaviour for hydrodynamics with vanishing sound speed. Using all these properties we propose a model unifying Dark Matter and Dark Energy in a single degree of freedom. In a certain limit this model exactly reproduces the evolution history of Lambda-CDM, while deviations away from the standard expansion history produce a potentially measurable difference in the evolution of structure.

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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