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arXiv · hep-th/0106189

Non-Commutative Gauge Theories and the Cosmological Constant

Adi Armoni·Rodolfo Russo
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Abstract

We discuss the issue of the cosmological constant in non-commutative non-supersymmetric gauge theories. In particular, in orbifold field theories non-commutativity acts as a UV cut-off. We suggest that in these theories quantum corrections give rise to a vacuum energy ρ, that is controlled by the non-commutativity parameter θ, ρ~ 1/theta^2 (only a soft logarithmic dependence on the Planck scale survives). We demonstrate our claim in a two-loop computation in field theory and by certain higher loop examples. Based on general expressions from string theory, we suggest that the vacuum energy is controlled by non-commutativity to all orders in perturbation theory.

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Adi Armoni, Rodolfo Russo. 2001-07-24. Non-Commutative Gauge Theories and the Cosmological Constant. https://doi.org/10.1103/physrevd.64.085016

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