Fermi paradox

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A graphical representation of the Arecibo message – Humanity's first attempt tae uise radio waves tae actively communicate its existence tae alien ceevilisations

The Fermi paradox (or Fermi's paradox) is the apparent contradiction atween heich estimates o the probability o the existence o extraterrestrial ceevilisations, such as in the Drake equation, an the lack o evidence for such ceevilisations.[1] The basic pynts o the argument, made bo pheesicists Enrico Fermi an Michael H. Hart, are:

  • The Sun is a teepical star, an thare are billions o starns in the galaxy that are billions o years older.[2][3]
  • Wi heich probability, some o these starns will hae Yird-lik planets,[4][5] an if the yird is teepical, some micht develop intelligent life.
  • Some o these ceevilisations micht develop interstellar travel, a step the Yird is investigatin nou.
  • Even at the slow pace o currently enveesioned interstellar travel, the Milky Way galaxy could be completely traversed in aboot a million years.[6]

Accordin tae this line of thinkin, the Yird should already hae been veesitit bi extraterrestrial aliens thou Fermi saw no convincin evidence o this, nor ony signs o alien intelligence onywhaur in the observable universe, leadin him tae ask, "Whaur is everybody?"[7][8]

References[eedit | eedit soorce]

  1. Krauthammer, C. (December 29, 2011). "Are we alone in the universe?". The Washington Post. Retrieved January 6, 2015.
  2. Chris Impe (2011). The Living Cosmos: Our Search for Life in the Universe. Cambridge University Press. ISBN 978-0-521-84780-3., page 282.
  3. Aguirre, V. Silva, G. R. Davies, S. Basu, J. Christensen-Dalsgaard, O. Creevey, T. S. Metcalfe, T. R. Bedding; et al. (2015). "Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology". Monthly Notices of the Royal Astronomical Society. 452 (2): 2127. arXiv:1504.07992. Bibcode:2015MNRAS.452.2127S. doi:10.1093/mnras/stv1388.CS1 maint: multiple names: authors leet (link) Accepted for publication in MNRAS. See Figure 15 in particular.
  4. Schilling, G. (June 13, 2012). "ScienceShot: Alien Earths Have Been Around for a While". Science. Retrieved January 6, 2015.
  5. Buchhave, L. A.; et al. (June 21, 2012). "An abundance of small exoplanets around stars with a wide range of metallicities". Nature. 486: 375. Bibcode:2012Natur.486..375B. doi:10.1038/nature11121.
  6. Hart, Michael H. (1975). "Explanation for the Absence of Extraterrestrials on Earth". Quarterly Journal of the Royal Astronomical Society. 16: 128–135. Bibcode:1975QJRAS..16..128H.
  7. Jones, E. M. (March 1, 1985). ""Where is everybody?" An account of Fermi's question"" (PDF). Los Alamos National Laboratory. OSTI 785733. Retrieved January 12, 2013.
  8. Overbye, Dennis (August 3, 2015). "The Flip Side of Optimism About Life on Other Planets". New York Times. Retrieved October 29, 2015.