Implications of Planck2015 for inflationary, ekpyrotic and anamorphic bouncing cosmologies
نویسندگان
چکیده
منابع مشابه
Stable Inflationary Dissipative Cosmologies
Inflationary cosmic expansions driven by a dissipative fluid has attracted some attention in the past as a mechanism able to solve the problems usually attached to the standard hot big-bang scenario (i.e. flatness, horizons, and monopoles abundance) different from those based on one (or more) scalar fields. The main dynamic effect of either the scalar field(s) or the dissipative fluid is to pro...
متن کاملBouncing Cosmologies and Self - Gravitational Corrections
A four-dimensional timelike brane is considered as the boundary of the SAdS 5 bulk background. Exploiting the CFT/FRW-cosmology relation, we derive the self-gravitational corrections to the first Friedmann-like equation which is the equation of the brane motion. The additional term that arises due to the semiclassical analysis, can be viewed as stiff matter where the self-gravitational correcti...
متن کاملConstraints on Generalized Inflationary Cosmologies
We consider cosmologies having an inflationary period during which the Robertson-Walker scale factor is an arbitrary function of time satisfying /~ > 0 (not necessarily an exponential). We show that any such inflationary period will produce long-wavelength gravitational waves which can affect present observations of the microwave background. Using present bounds on the quadrupole anisotropy we ...
متن کاملStructure Formation in Inflationary Cosmologies
A brief account is given of large-scale structure modelling based on the assumption that the initial perturbations arise from inflation. A recap is made of the implications of inflation for large-scale structure; under the widely applicable slow-roll paradigm inflation adds precisely two extra parameters to the normal scenarios, which can be taken to be the tilt of the density perturbation spec...
متن کاملFalsifying Tree Level String Motivated Bouncing Cosmologies
The string effective action at tree level contains, in its bosonic sector, the Einstein-Hilbert term, the dilaton, and the axion, besides scalar and gauge fields coming from the Ramond-Ramond sector. The reduction to four dimensions brings to scene moduli fields. We generalize this effective action by introducing two arbitrary parameters, ω and m, connected with the dilaton and axion couplings....
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Classical and Quantum Gravity
سال: 2016
ISSN: 0264-9381,1361-6382
DOI: 10.1088/0264-9381/33/4/044001