Vacuum energy

Vacuum energy is an underlying background energy that exists in space throughout the entire universe.[1] The vacuum energy is a special case of zero-point energy that relates to the quantum vacuum.[2]

Unsolved problem in physics:
Why does the zero-point energy of the vacuum not cause a large cosmological constant? What cancels it out?

The effects of vacuum energy can be experimentally observed in various phenomena such as spontaneous emission, the Casimir effect, and the Lamb shift, and are thought to influence the behavior of the Universe on cosmological scales. Using the upper limit of the cosmological constant, the vacuum energy of free space has been estimated to be 10−9 joules (10−2 ergs), or ~5 GeV per cubic meter.[3] However, in quantum electrodynamics, consistency with the principle of Lorentz covariance and with the magnitude of the Planck constant suggests a much larger value of 10113 joules per cubic meter. This huge discrepancy is known as the cosmological constant problem or, colloquially, the "vacuum catastrophe."[4]

  1. ^ Battersby, Stephen. "It's confirmed: Matter is merely vacuum fluctuations". New Scientist. Retrieved 2020-06-18.
  2. ^ Scientific American. 1997. FOLLOW-UP: What is the 'zero-point energy' (or 'vacuum energy') in quantum physics? Is it really possible that we could harness this energy? – Scientific American. [ONLINE] Available at: http://www.scientificamerican.com/article/follow-up-what-is-the-zer/. [Accessed 27 September 2016].
  3. ^ Sean Carroll, Senior Research Associate – Physics, California Institute of Technology, June 22, 2006. C-SPAN broadcast of Cosmology at Yearly Kos Science Panel, Part 1.
  4. ^ Adler, Ronald J.; Casey, Brendan; Jacob, Ovid C. (1995). "Vacuum catastrophe: An elementary exposition of the cosmological constant problem". American Journal of Physics. 63 (7): 620–626. Bibcode:1995AmJPh..63..620A. doi:10.1119/1.17850. ISSN 0002-9505.