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Cosmological Constant as Vacuum Energy Density of Quantum Field Theories on Noncommutative Spacetime

Xiao-Jun Wang
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Abstract

We propose a new approach to understand hierarchy problem for cosmological constant in terms of considering noncommutative nature of space-time. We calculate that vacuum energy density of the noncommutative quantum field theories in nontrivial background, which admits a smaller cosmological constant by introducing an higher noncommutative scale $μ_{NC}\sim M_p$. The result $ρ_Λ\sim 10^{-6}Λ_{SUSY}^8M_p^4/μ_{NC}^8$ yields cosmological constant at the order of current observed value for supersymmetry breaking scale at 10TeV. It is the same as Banks' phenomenological formula for cosmological constant.

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Xiao-Jun Wang. 2004-12-15. Cosmological Constant as Vacuum Energy Density of Quantum Field Theories on Noncommutative Spacetime. https://arxiv.org/abs/hep-th/0412084

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