Effective state metamorphosis in semi-classical loop quantum cosmology

被引:52
作者
Singh, P [1 ]
机构
[1] Penn State Univ, Inst Gravitat Phys & Geometry, University Pk, PA 16802 USA
关键词
D O I
10.1088/0264-9381/22/20/003
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
Modification to the behaviour of geometrical density at short scales is a key result of loop quantum cosmology, responsible for an interesting phenomenology in the very early universe. We demonstrate the way matter with arbitrary scale factor dependence in Hamiltonian incorporates this change in its effective dynamics in the loop-modified phase. For generic matter, the equation of state starts varying near a critical scale factor, becomes negative below it and violates the strong energy condition. This opens a new avenue to generalize various phenomenological applications in loop quantum cosmology. We show that different ways to define energy density may yield radically different results, especially for the case corresponding to classical dust. We also discuss implications for frequency dispersion induced by modification to geometric density at small scales.
引用
收藏
页码:4203 / 4216
页数:14
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