One of the most interesting aspects of vacuum energy (with or without mirrors) is that, calculated in quantum field theory, it is infinite! (scientificamerican.com)
The football is where the crew and robotic systems would be, while the ring would contain exotic matter called negative vacuum energy, a consequence of quantum mechanics. (newscientist.com)
The possibilities being discussed for dark energy range from quantum vacuum energy to the influence of the unseen extra dimensions predicted by string theory. (discovermagazine.com)