Non-Gaussian signatures from the postinflationary early universe.
نویسندگان
چکیده
We consider contributions to non-Gaussianity of the cosmic microwave background (CMB) from remnants of phase transitions in the very early Universe. Such signatures can optimistically be used to discover evidence of new particle physics through cosmological observations. More conservatively they may provide an obstacle to extracting information about the non-Gaussian nature of primordial density fluctuations from any detection in the CMB. We study this explicitly by computing the bispectrum from global textures, which occur in a wide class of particle physics models.
منابع مشابه
ar X iv : 0 81 1 . 21 76 v 2 [ as tr o - ph ] 6 D ec 2 00 9 Non - Gaussian Signatures from the Postinflationary Early Universe
We consider contributions to non-Gaussianity of the Cosmic Microwave Background (CMB) from remnants of phase transitions in the very early universe. Such signatures can optimistically be used to discover evidence of new particle physics through cosmological observations. More conservatively they may provide an obstacle to extracting information about the non-Gaussian nature of primordial densit...
متن کاملNon-Gaussianity: Comparing wavelet and Fourier based methods
In the context of the present and future Cosmic Microwave Background (CMB) experiments, going beyond the information provided by the power spectrum has become necessary in order to tightly constrain the cosmological model. The non-Gaussian signatures in the CMB represent a very promising tool to probe the early universe and the structure formation epoch. We present the results of a comparison b...
متن کاملLensing-induced Non-Gaussian Signatures in the Cosmic Microwave Background
We propose a new method for extracting the non-Gaussian signatures on the isotemperature statistics in the cosmic microwave background (CMB) sky, which is induced by the gravitational lensing due to the intervening large-scale structure of the universe. To develop the method, we focus on a specific statistical property of the intrinsic Gaussian CMB field; a field point in the map that has a lar...
متن کاملThe Cosmological Moduli Problem, Supersymme- Try Breaking , and Stability in Postinflationary Cos- Mology
We review scenarios that have been proposed to solve the cosmological problem caused by moduli in string theory, the Postmodern Polonyi Problem (PPP). In particular, we discuss the difficulties encountered by the apparently " trivial " solution of this problem, in which moduli masses are assumed to arise from nonperturbative, SUSY preserving, dynamics at a scale higher than that of SUSY breakin...
متن کاملEarly Universe Sources for Cmb Non-gaussianity
The common belief that the CMB is Gaussian distributed can be directly traced back to the generic assumption that the quantum fluctuations of the inflaton field are placed in the vacuum state 1. Relaxing this assumption might lead to detectable signatures in various astrophysical tests, most interestingly in future CMB and large-scale structure observations. In this note, we study CMB non-Gauss...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Physical review letters
دوره 103 25 شماره
صفحات -
تاریخ انتشار 2009