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arXiv · hep-th/9705188

Higher Loop Effects in M(atrix) Orbifolds

Ori J. Ganor·Rajesh Gopakumar·Sanjaye Ramgoolam
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Abstract

Scattering of zero branes off the fixed point in $R^8/Z_2$, as described by a super-quantum mechanics with eight supercharges, displays some novel effects relevant to Matrix theory in non-compact backgrounds. The leading long distance behaviour of the moduli space metric receives no correction at one loop in Matrix theory, but does receive a correction at two loops. There are no contributions at higher loops. We explicitly calculate the two-loop term, finding a non-zero result. We find a discrepancy with M(atrix)-theory. Although the result has the right dependence on $v$ and $b$ for the scattering of zero branes off the fixed point the factors of $N$ do not match. We also discuss scattering in the orbifolds, $R^5/Z_2$ and $R^9/Z_2$ where we find the predicted fractional charges.

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Ori J. Ganor, Rajesh Gopakumar, Sanjaye Ramgoolam. 1997-06-08. Higher Loop Effects in M(atrix) Orbifolds. https://doi.org/10.1016/s0550-3213(97)00654-8

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