If relativity theory is correct, no object can travel forward in time at a speed greater than the speed of light  Yet quantum mechanics predicts that the tachyon, a hypothetical subatomic particle, travels faster than light
Thus, if relativity theory is correct, either quantum mechanics' prediction about tachyons is erroneous or tachyons travel backward in time
The human brain can survive without oxygen only for a few minutes, according to modern medicine. Surprisingly, a reliable witness reported that a shaman has survived for an entire week buried five feet underground. Thus, if modern medicine is not wrong, either the witness is mistaken or the shaman's brain did not suffer any lack of oxygen.