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arXiv · hep-th/0005211

The Type I D-instanton and its M-theory Origin

Tathagata Dasgupta·Matthias R. Gaberdiel·Michael B. Green
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Abstract

The tree-level amplitude for the scattering of two gauge particles constrained to move on the two distinct boundaries of eleven-dimensional space-time in the Horava-Witten formulation of M-theory is constructed. At low momenta this reproduces the corresponding tree-level scattering amplitude of the E_8xE_8 heterotic string theory. After compactification to nine dimensions on a large circle with a suitable Wilson line to break the symmetry to SO(16)xSO(16) this amplitude is used to describe the scattering of two massive SO(16) spinor states - one from each factor of the unbroken symmetry group. The amplitude contains a component that is associated with the exchange of a Kaluza-Klein charge between the boundaries, which is interpreted as the exchange of a D-particle between orientifold planes in the Type IA theory. This is related by T-duality to the effect of a non-BPS D-instanton in the Type I theory which is only invariant under those elements of O(16)xSO(16) that are in SO(16)xSO(16).

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Tathagata Dasgupta, Matthias R. Gaberdiel, Michael B. Green. 2000-05-23. The Type I D-instanton and its M-theory Origin. https://doi.org/10.1088/1126-6708%2F2000%2F08%2F004

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