Quantum physics predicts the existence of an underlying sea of zero-point energy at every spot in the universe. This is different from the cosmic microwave background and is also referred to as the electromagnetic quantum vacuum, since it is the lowest energy state of otherwise empty space. This energy is so enormous that most physicists believe that even though zero-point energy seems to be an inescapable consequence of elementary quantum theory, it cannot be physically real. However, a minority of physicists accept it as real energy that we cannot directly sense because it is the same everywhere, even inside our bodies and measuring devices. From this perspective, the ordinary world of matter and energy is like a foam atop the quantum vacuum sea. It does not matter to a ship how deep the ocean is below it. If zero-point energy is real, there is the possibility...