Evolution of curvature and anisotropy near a nonsingular bounce
نویسندگان
چکیده
منابع مشابه
Cosmological perturbations across a curvature bounce
String-inspired cosmologies, whereby a non-singular curvature bounce is induced by a general-covariant, T -duality-invariant, non-local dilaton potential, are used to study numerically how inhomogeneities evolve and to compare the outcome with analytic expressions obtained through different matching conditions across the bounce. Good agreement is found if continuity across the bounce is assumed...
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متن کاملUnstable growth of curvature perturbations in nonsingular bouncing cosmologies.
Bouncing cosmologies require an ekpyrotic contracting phase (w≫1) in order to achieve flatness, homogeneity, and isotropy. Models with a nonsingular bounce further require a bouncing phase that violates the null energy condition (w<-1). We show that the transition from the ekpyrotic phase to the bouncing phase creates problems for cosmological perturbations. A component of the adiabatic curvatu...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2011
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.84.083520