Yes, I have heard of Maglev, and no, anti-gravity technology is not used in roller coasters. Merely simple Newtonian physics.<quoted text>
which ones are fakes and fraud?
Ever heard of Maglev (magnetic levitation) trains?
also, anti-gravity technology is used in roller coasters
Of the people you referred to one proven fake is Hutchinson. But anyone who makes a claim that cannot be reproduced can safely be assumed to be a fraud.