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Published on: May 3, 2019
Universal Bound on the Duration of a Kination Era
Cem Eröncel1, Yann Gouttenoire2,3, Ryosuke Sato4
1İstinye University, Faculty of Engineering and Natural Sciences, 34396, İstanbul, Türkiye.
None:
We show that primordial adiabatic curvature fluctuations generate an instability of the scalar field sourcing a kination era. We demonstrate that the generated higher Fourier modes constitute a radiationlike component dominating over the kination background after about 11 e-folds of cosmic expansion. Current constraints on the extra number of neutrino flavors ΔN_{eff} thus imply the observational bound of approximately 10 e-folds, representing the most stringent bound to date on the stiffness of the equation of state of the pre-Big Bang-nucleosynthesis universe.
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