The cosmological constant is probably zero, and a proof is possibly right
نویسندگان
چکیده
منابع مشابه
The Cosmological Constant Is Back
SUMMARY A diverse set of observations now compellingly suggest that Universe possesses a nonzero cosmological constant. In the context of quantum-field theory a cosmological constant corresponds to the energy density of the vacuum, and the wanted value for the cosmological constant corresponds to a very tiny vacuum energy density. We discuss future observational tests for a cosmological constan...
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We consider a recent proposal to solve the cosmological constant problem within the context of brane world scenarios with infinite volume extra dimensions. In such theories bulk can be supersymmetric even if brane supersymmetry is completely broken. The bulk cosmological constant can therefore naturally be zero. Since the volume of the extra dimensions is infinite, it might appear that at large...
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A general condition for the existence of fermion zero modes is derived for the M-5brane, the M-2-brane and the D = 4, N = 2 Majumdar-Papapetrou 0-brane. The fermion zero modes of these p-branes do not exist if the supersymmetry spinor generator goes to a constant at the horizon and they exist only if it vanishes there. In particular it is shown that the fermion zero mode of the M-2-brane in D =...
متن کاملv 1 4 J an 1 99 9 IS THE COSMOLOGICAL CONSTANT NON - ZERO ?
The present talk is similar to one at COSMO-98 last month. As is well explained in standard reviews of the cosmological constant [1, 2] the theoretical expectation for Λ exceeds its observational value by 120 orders of magnitude. In 1917, Einstein looked for a static solution of general relativity for cosmology and added a new λ term:
متن کاملWhy the cosmological constant is small and positive.
Within conventional big bang cosmology, it has proven to be very difficult to understand why today's cosmological constant is so small. In this paper, we show that a cyclic model of the universe can naturally incorporate a dynamical mechanism that automatically relaxes the value of the cosmological constant, including contributions to the vacuum density at all energy scales. Because the relaxat...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2008
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2007.12.019