Limits on low scale gravity from e+e−→W+W−, ZZ and γγ

It has been proposed recently that the scale of quantum gravity (“the string scale”) can be MS∼few TeV with n≥2 extra dimensions of size R≲mm so that, at distances greater than R, Newtonian gravity with MPl∼1018 GeV is reproduced if MPl2∼RnMSn+2. Exchange of virtual gravitons in this theory generates higher-dimensional operators involving SM fields, suppressed by powers of MS. We discuss constraints on this scenario from the contribution of these operators to the processes e+e−→W+W−, ZZ, γγ. We find that LEP2 can place a limit MS≈1 TeV from e+e−→W+W−, ZZ, γγ.