期刊
INTERNATIONAL JOURNAL OF MODERN PHYSICS D
卷 20, 期 13, 页码 2449-2469出版社
WORLD SCIENTIFIC PUBL CO PTE LTD
DOI: 10.1142/S0218271811020457
关键词
Modified gravity; particle production; singularity theory; thermodynamics
资金
- CNPq (Brazil)
- IMSP-UAC
We investigate particle production in an expanding universe under the assumption that the Lagrangian contains the Einstein term R plus a modified gravity term of the form R-alpha, where alpha is a constant. Dark fluid is considered as the main content of the universe and the big rip singularity appears. Quantum effects due to particle creation is analyzed near the singularity and we find that for alpha is an element of ]1/2, 1[, quantum effects are dominant and the big rip may be avoided whereas for alpha is an element of J the dark fluid is dominant and the singularity remains. The Cardy-Verlinde formula is also introduced and its equivalence with the total entropy of the universe is checked. It is found that this can always occur in Einstein gravity while in f(R) gravity, it holds only for alpha = n+1/2n+6, n being the space dimension, corresponding to the situation in which the big rip cannot be avoided.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据