The Hunted Earth Series by Roger MacBride Allen

The first book in the Hunted Earth series, published to tie in with the hardcover publication of its sequel, The Shattered Sphere.The Earth has disappeared, but was it destroyed by an unauthorized gravity experiment, or was the planet kidnapped by an alien race? Humanity must discover the answer before it's too late.

Striving to retrieve a stolen planet Earth and restore it to its proper solar system, an unlikely band of human scientists, dictators, and professional troublemakers face two enemies in the powerful Charonians and the mysterious Adversary. Reprint.