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A supersymmetric D-brane Model of Space-Time Foam

John Ellis·Nikolaos E. Mavromatos·Michael Westmuckett
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Abstract

We present a supersymmetric model of space-time foam with two stacks of eight D8-branes with equal string tensions, separated by a single bulk dimension containing D0-brane particles that represent quantum fluctuations in the space-time foam. The ground state configuration with static D-branes has zero vacuum energy. However, gravitons and other closed-string states propagating through the bulk may interact with the D0-particles, causing them to recoil and the vacuum energy to become non zero. This provides a possible origin of dark energy. Recoil also distorts the background metric felt by energetic massless string states, which travel at less than the usual (low-energy) velocity of light. On the other hand, the propagation of chiral matter anchored on the D8 branes is not affected by such space-time foam effects.

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John Ellis, Nikolaos E. Mavromatos, Michael Westmuckett. 2004-05-12. A supersymmetric D-brane Model of Space-Time Foam. https://doi.org/10.1103/physrevd.70.044036

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