Browne, Malcolm W. (1990年8月21日). “New Direction in Physics: Back in Time”. The New York Times. https://www.nytimes.com/1990/08/21/science/new-direction-in-physics-back-in-time.html?pagewanted=all2010年5月22日閲覧. "According to quantum theory, the vacuum contains neither matter nor energy, but it does contain fluctuations, transitions between something and nothing in which potential existence can be transformed into real existence by the addition of energy.(Energy and matter are equivalent, since all matter ultimately consists of packets of energy.) Thus, the vacuum's totally empty space is actually a seething turmoil of creation and annihilation, which to the ordinary world appears calm because the scale of fluctuations in the vacuum is tiny and the fluctuations tend to cancel each other out."
