Inflation in f(R) modified gravity /
Maha Salah Abdelmoneim
Inflation in f(R) modified gravity / Maha Salah Abdelmoneim ; Supervised Ahmad A. Amer , Shaaban S. Khalil - Cairo : Maha Salah Abdelmoneim , 2017 - 68 P. ; 25cm
Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Mathematics
Despite some of its successful features, the standard big bang cosmology suers from many problems. The Flatness and Horizon problems are two of its main un- solved problems. Inationary cosmology is an alternative framework to standard cosmology within which the ination solves some of these problems eciently. Many scenarios of ination are invented. The original version of ination was based on adding a scalar eld to the energy-momentum at the early Universe whose dynamics causes the ination. Other alternatives depend on modifying the geometrical part of the general theory of relativity. The f(R) modied theory of gravity is one of the most straightforward generalizations of such examples. However f(R) serves again as the general relativity minimally coupled with a geometry-inspired scalar degree of freedom. Ination in f(R) theories is one of the active topics of research these days. Ination in the framework of f(R) modied gravity is revisited. We study the conditions that f(R) should satisfy in order to lead to a viable inationary model in the original form and in the Einstein frame. Based on these criteria we propose a new logarithmic model as a potential candidate for f(R) theories aiming to de- scribe ination consistent with observations from planck satellite (2015). The model predicts scalar spectral index 0.9615
f(R) Inflation Modified gravity
Inflation in f(R) modified gravity / Maha Salah Abdelmoneim ; Supervised Ahmad A. Amer , Shaaban S. Khalil - Cairo : Maha Salah Abdelmoneim , 2017 - 68 P. ; 25cm
Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Mathematics
Despite some of its successful features, the standard big bang cosmology suers from many problems. The Flatness and Horizon problems are two of its main un- solved problems. Inationary cosmology is an alternative framework to standard cosmology within which the ination solves some of these problems eciently. Many scenarios of ination are invented. The original version of ination was based on adding a scalar eld to the energy-momentum at the early Universe whose dynamics causes the ination. Other alternatives depend on modifying the geometrical part of the general theory of relativity. The f(R) modied theory of gravity is one of the most straightforward generalizations of such examples. However f(R) serves again as the general relativity minimally coupled with a geometry-inspired scalar degree of freedom. Ination in f(R) theories is one of the active topics of research these days. Ination in the framework of f(R) modied gravity is revisited. We study the conditions that f(R) should satisfy in order to lead to a viable inationary model in the original form and in the Einstein frame. Based on these criteria we propose a new logarithmic model as a potential candidate for f(R) theories aiming to de- scribe ination consistent with observations from planck satellite (2015). The model predicts scalar spectral index 0.9615
f(R) Inflation Modified gravity