分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-05-08
摘要: We discuss a class of matrix models describing cosmology with a light-like singularity, generalizing the model proposed by Craps et al. in hep-th/0506180.
分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-05-08
摘要: We study a class of models in which the inflaton is minimally coupled to gravity with a term f(R)phiv2. We focus in particular on the case where f~R2, and the expansion of the scale factor is driven by the usual potential energy, while the rolling of the inflaton is driven by the non-minimal coupling. We show that the power spectrum is in general blue, and the problem of getting a running spectral index is eased. However, the inflaton potential must have a large second derivative in order to get a large running.
分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-05-08
摘要: We investigate the measure problem in the framework of inflationary cosmology. The measure of the history space is constructed and applied to inflationmodels. Using this measure, it is shown that the probability for the generalized single-field slow roll inflation to last for N e-folds is suppressed by a factor exp(-3N), and the probability for the generalized n-field slow roll inflation is suppressed by a much larger factor, exp(-3nN). Some non-inflationary models such as the cyclic model do not suffer from this difficulty.
分类: 物理学 >> 交叉学科物理及相关领域的科学与技术 提交时间: 2016-05-08
摘要: Cell cycle; Replication initiation; Cell growth; DnaA; RNA polymerase