arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1108.0874hep-thastro-ph.COgr-qc
收藏

暴胀中标量扰动的共形不变性

Conformal invariance of scalar perturbations in inflation

Paolo Creminelli

摘要:

在暴胀模型中,标量扰动的源不是暴胀子,而是一个或多个与暴胀子耦合可以忽略的标量,所产生的扰动不仅是尺度不变的,而且是完全共形不变的,共形维数接近于零。这与关联函数只能依赖于de Sitter不变距离的事实密切相关。这些性质来自暴胀德西特空间的等距性,因此完全独立于动力学。3点函数是固定的两个常数,而4点函数是两个参数的函数(而不是在没有共形不变性的情况下的五个)。我们在一个显式例子中表明,在傅立叶空间中可以直接检验复变子的共形不变性。非共形关联函数的检测,例如等边3点函数,将意味着扰动源不与暴胀子解耦。

英文摘要:

In inflationary models where the source of scalar perturbations is not the inflaton, but one or more scalars with negligible coupling with the inflaton, the resulting perturbations are not only scale invariant, but fully conformally invariant with conformal dimension close to zero. This is closely related to the fact that correlation functions can only depend on the de Sitter invariant distances. These properties follow from the isometries of the inflationary de Sitter space and are thus completely independent of the dynamics. The 3-point function is fixed in terms of two constants, while the 4-point function is a function of two parameters (instead of five as in the absence of conformal invariance). The conformal invariance of correlators can be directly checked in Fourier space, as we show in an explicit example. A detection of a non-conformal correlation function, for example an equilateral 3-point function, would imply that the source of perturbations is not decoupled from the inflaton.

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。

↑