Why on earth would anyone want to be physically immortal? This world is a boring, hellish joke played on humans by the false gods of the material universe. Nearly everything you can experience here you can enjoy to an even greater degree in the incorporeal realms. Those that wish to exist eternally in the 3D universe are just suffering from an intractable addiction to domination and hubris - they'd rather rule in a hell of their own making than exist in harmony and equality with their fellow men in heaven. It's utterly psychotic to wish for immortality on this planet. It's a curse, not a blessing.