منابع مشابه
Inflation from Extra Dimensions
A gravity-driven inflation is shown to arise from a simple higher dimensional universe. In vacuum, the shear of n > 1 contracting dimensions is able to inflate the remaining three spatial dimensions. Said another way, the expansion of the 3-volume is accelerated by the contraction of the n-volume. Upon dimensional reduction, the theory is equivalent to a four dimensional cosmology with a dynami...
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The radial mode of n extra compact dimensions (the radion, b) can cause inflation in theories where the fundamental gravity scale, M , is smaller than the Planck scale MP . For radion potentials V (b) with a simple polynomial form, to get the observed density perturbations, the energy scale of V (b) must greatly exceed M ∼ 1 TeV: V (b) ≡ MV ∼ 10−4MP . This gives a large radion mass and reheat t...
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A brief review of the recent developments in the physics from extra dimensions is given with a focus on the effects of Kaluza-Klein excitations in the Standard Model sector. It is shown that the current accurate data on the Fermi constant and on other electro-weak parameters puts a lower bound on the scale of extra dimensions of∼ 3 TeV, and thus the observation of such dimensions lies beyond th...
متن کاملGraviton production from extra dimensions
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متن کاملGravitational Excitons from Extra Dimensions
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2011
ISSN: 1550-7998,1550-2368
DOI: 10.1103/physrevd.84.125020