Of course the recent stings for luring start out with an over 18 provider and then switch after the defendant is teased and develops blue balls to an under 18 provider.

However what would be the outcome of analysis of the theory of time continuum special relativity applied about this matter?

Time dilation formula is = change in time / square root (1 - velocity^2/speed of light^2)

Thus if we start on earth 18 years ago with two identical twin girls.  Then keep one girl on Earth for 18 years whereas the other girl is put on a spaceship traveling on a trajectory at approximately 69% of the speed of light.  Then if the government created a wormhole in the space time continuum allowing instant messaging for the sting and if the defendant on Earth asks to have sex with the girl in the spaceship, she would only be 13 years old despite the fact that her sister was be aged 18 and they were born at the same time as identical twins.

Thus, the government must prove in order to convict the defendants for luring a minor, that the minor was not subject to high speed travel during her lifetime and that time dialation relative to the inertial reference frame of Earth's space time continuum did not occur.  

Because of this no probable cause existed for the sting arrests and the cases must be dismissed under the holding of the theory of special relativity.