arXiv 1903.044192019-03-02astro-ph.CO

原始磁场的宇宙学特征

Cosmological Features of Primordial Magnetic Fields

Hector J. Hortua

备注：: PhD Thesis, defended on 23 October 2018, 167 pages. http://bdigital.unal.edu.co/70714/

摘要：

本论文的目的是研究由于原始磁场对CMB各向异性的影响，并分析一些有利的情况下，由这些签名，包括限制的磁场振幅的边界上CMB非高斯模型和背景模型的约束磁成因。事实上，我们发现，螺旋在字段中起着重要的作用，在分析保偏光纤的起源，通过产生显着的功能，在互相关偏振模式和减少CMB双谱中的信号的增加。在后一种情况下，我们报告说，非因果场（主要是在通货膨胀时期产生的）是最有利的模型约束的CMB观测。此外，我们还研究了存在的红外截止光谱和双谱发现吸引人的独特功能，从原始磁场。本论文的另一个重要结果是在磁化背景下宇宙学扰动理论的不同方法之间的等价性。事实上，假设一个磁化的宇宙，并在两种方法中建立规范不变量：1+ 3协变和规范不变;我们发现这些不变量代表相同的物理意义。此外，我们还定义了与电磁势相关的规范不变量，这将有助于我们在未来的工作中研究扰动情况下的磁成因模型。

英文摘要：

The aim of this thesis is to study the effects on the CMB anisotropy due to primordial magnetic fields and to analyze some favorable scenarios of magnetogenesis constrained by those signatures, including limits on the amplitude of the fields from bounds on CMB non-Gaussianity and background models. In fact, we found out that helicity in the fields plays an important role in the analysis PMFs origin, by generating significant features in the cross-correlation polarization pattern and the increasing of the signal in the reduced CMB bispectrum. In the latter case, we reported that non-causal fields (mainly generated during the inflation epoch) are the most favorable models constrained by CMB observations. Moreover, we have studied the presence of an IR cutoff in the spectra and bispectra finding appealing unique features from primordial magnetic fields. Another important result shown in this thesis is the equivalence between different approaches of cosmological perturbation theory in the magnetized context. In fact, assuming a magnetized Universe and building gauge invariant quantities in both approaches: the 1+3covariant and the gauge invariant; we found out that those invariants represent the same physical meaning. Besides, we define gauge invariant related to the electromagnetic potentials which in future works, could help us to study magnetogenesis models on perturbed scenarios.

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。

摘要：

英文摘要：

相关论文