Timeline of cosmological theories

This timeline of cosmological theories and discoveries is a chronological record of the development of humanity's understanding of the cosmos over the last two-plus millennia. Modern cosmological ideas follow the development of the scientific discipline of physical cosmology.




  • 1950 Fred Hoyle coins the term "Big Bang", saying that it was not derisive; it was just a striking image meant to highlight the difference between that and the Steady-State model.
  • 1961 Robert Dicke argues that carbon-based life can only arise when the gravitational force is small, because this is when burning stars exist; first use of the weak anthropic principle
  • 1963 - Maarten Schmidt discovers the first quasar; these soon provide a probe of the universe back to substantial redshifts.
  • 1965 Hannes Alfvén proposes the now-discounted concept of ambiplasma to explain baryon asymmetry and supports the idea of an infinite universe.
  • 1965 Martin Rees and Dennis Sciama analyze quasar source count data and discover that the quasar density increases with redshift.
  • 1965 Arno Penzias and Robert Wilson, astronomers at Bell Labs discover the 2.7 K microwave background radiation, which earns them the 1978 Nobel Prize in Physics. Robert Dicke, James Peebles, Peter Roll and David Todd Wilkinson interpret it as a relic from the big bang.
  • 1966 Stephen Hawking and George Ellis show that any plausible general relativistic cosmology is singular
  • 1966 James Peebles shows that the hot Big Bang predicts the correct helium abundance
  • 1967 Andrei Sakharov presents the requirements for baryogenesis, a baryon-antibaryon asymmetry in the universe
  • 1967 John Bahcall, Wal Sargent, and Maarten Schmidt measure the fine-structure splitting of spectral lines in 3C191 and thereby show that the fine-structure constant does not vary significantly with time
  • 1967 — Robert Wagoner, William Fowler, and Fred Hoyle show that the hot Big Bang predicts the correct deuterium and lithium abundances
  • 1968 Brandon Carter speculates that perhaps the fundamental constants of nature must lie within a restricted range to allow the emergence of life; first use of the strong anthropic principle
  • 1969 Charles Misner formally presents the Big Bang horizon problem
  • 1969 — Robert Dicke formally presents the Big Bang flatness problem
  • 1970 Vera Rubin and Kent Ford measure spiral galaxy rotation curves at large radii, showing evidence for substantial amounts of dark matter.
  • 1973 Edward Tryon proposes that the universe may be a large scale quantum mechanical vacuum fluctuation where positive mass-energy is balanced by negative gravitational potential energy
  • 1976 — Alex Shlyakhter uses samarium ratios from the Oklo prehistoric natural nuclear fission reactor in Gabon to show that some laws of physics have remained unchanged for over two billion years
  • 1977 — Gary Steigman, David Schramm, and James Gunn examine the relation between the primordial helium abundance and number of neutrinos and claim that at most five lepton families can exist.
  • 1980 Alan Guth and Alexei Starobinsky independently propose the inflationary Big Bang universe as a possible solution to the horizon and flatness problems.
  • 1981 — Viacheslav Mukhanov and G. Chibisov propose that quantum fluctuations could lead to large scale structure in an inflationary universe.
  • 1982 — The first CfA galaxy redshift survey is completed.
  • 1982 — Several groups including James Peebles, J. Richard Bond and George Blumenthal propose that the universe is dominated by cold dark matter.
  • 1983 - 1987  — The first large computer simulations of cosmic structure formation are run by Davis, Efstathiou, Frenk and White. The results show that cold dark matter produces a reasonable match to observations, but hot dark matter does not.
  • 1988 — The CfA2 Great Wall is discovered in the CfA2 redshift survey.
  • 1988 — Measurements of galaxy large-scale flows provide evidence for the Great Attractor.
  • 1990 — Preliminary results from NASA's COBE mission confirm the cosmic microwave background radiation has a blackbody spectrum to an astonishing one part in 105 precision, thus eliminating the possibility of an integrated starlight model proposed for the background by steady state enthusiasts.
  • 1992 — Further COBE measurements discover the very small anisotropy of the cosmic microwave background, providing a "baby picture" of the seeds of large-scale structure when the universe was around 1/1100th of its present size and 380,000 years old.
  • 1996 - The first Hubble Deep Field is released, providing a clear view of very distant galaxies when the universe was around one-third of its present age.
  • 1998 — Controversial evidence for the fine structure constant varying over the lifetime of the universe is first published.
  • 1998 — The Supernova Cosmology Project and High-Z Supernova Search Team discover cosmic acceleration based on distances to Type Ia supernovae, providing the first direct evidence for a non-zero cosmological constant.
  • 1999 — Measurements of the cosmic microwave background radiation with finer resolution than COBE, (most notably by the BOOMERanG experiment see Mauskopf et al., 1999, Melchiorri et al., 1999, de Bernardis et al. 2000) provide evidence for oscillations (the first acoustic peak) in the anisotropy angular spectrum, as expected in the standard model of cosmological structure formation. The angular position of this peak indicates that the geometry of the universe is close to flat.

Since 2000

See also

Physical cosmology

Belief systems



  1. Horowitz (1998), p.xii
  2. Aristotle; Forster, E. S. (Edward Seymour), 1879-1950; Dobson, J. F. (John Frederic), 1875-1947 (1914). De Mundo. p. 2.
  3. "Introduction to Astronomy, Containing the Eight Divided Books of Abu Ma'shar Abalachus". World Digital Library. 1506. Retrieved 2013-07-16.
  4. Adi Setia (2004), "Fakhr Al-Din Al-Razi on Physics and the Nature of the Physical World: A Preliminary Survey", Islam & Science, 2, archived from the original on 2012-07-10, retrieved 2010-03-02
  5. Muammer İskenderoğlu (2002), Fakhr al-Dīn al-Rāzī and Thomas Aquinas on the question of the eternity of the world, Brill Publishers, p. 79, ISBN 90-04-12480-2
  6. John Cooper (1998), "al-Razi, Fakhr al-Din (1149-1209)", Routledge Encyclopedia of Philosophy, Routledge, retrieved 2010-03-07
  7. Staff (March 17, 2014). "BICEP2 2014 Results Release". National Science Foundation. Retrieved March 18, 2014.
  8. Clavin, Whitney (March 17, 2014). "NASA Technology Views Birth of the Universe". NASA. Retrieved March 17, 2014.
  9. Overbye, Dennis (March 17, 2014). "Space Ripples Reveal Big Bang's Smoking Gun". The New York Times. Retrieved March 17, 2014.
  10. Overbye, Dennis (March 24, 2014). "Ripples From the Big Bang". New York Times. Retrieved March 24, 2014.
  11. 1 2 Ade, P.A.R.; BICEP2 Collaboration (June 19, 2014). "Detection of B-Mode Polarization at Degree Angular Scales by BICEP2" (PDF). Physical Review Letters. 112: 241101. arXiv:1403.3985. Bibcode:2014PhRvL.112x1101B. doi:10.1103/PhysRevLett.112.241101. PMID 24996078. Retrieved June 20, 2014.
  12. http://www.math.columbia.edu/~woit/wordpress/?p=6865
  13. Overbye, Dennis (June 19, 2014). "Astronomers Hedge on Big Bang Detection Claim". New York Times. Retrieved June 20, 2014.
  14. Amos, Jonathan (June 19, 2014). "Cosmic inflation: Confidence lowered for Big Bang signal". BBC News. Retrieved June 20, 2014.
  15. Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P. (2016-02-11). "Observation of Gravitational Waves from a Binary Black Hole Merger". Physical Review Letters. 116 (6): 061102. arXiv:1602.03837. Bibcode:2016PhRvL.116f1102A. doi:10.1103/PhysRevLett.116.061102. ISSN 0031-9007. PMID 26918975.
  16. Castelvecchi, Davide; Witze, Alexandra (11 February 2016). "Einstein's gravitational waves found at last". Nature News. doi:10.1038/nature.2016.19361. Retrieved 11 February 2016.
  17. Blum, Alexander; Lalli, Roberto; Renn, Jürgen (12 February 2016). "The long road towards evidence". Max Planck Society. Retrieved 15 February 2016.
  18. Abbott, B. P.; et al. (LIGO Scientific Collaboration and Virgo Collaboration) (15 June 2016). "GW151226: Observation of Gravitational Waves from a 22-Solar-Mass Binary Black Hole Coalescence". Physical Review Letters. 116 (24): 241103. arXiv:1606.04855. Bibcode:2016PhRvL.116x1103A. doi:10.1103/PhysRevLett.116.241103. PMID 27367379.
  19. Commissariat, Tushna (15 June 2016). "LIGO detects second black-hole merger". Physics World. Institute of Physics. Retrieved 15 June 2016.
  • Horowitz, Wayne (1998). Mesopotamian cosmic geography. Eisenbrauns. 
  • Bunch, Bryan, and Alexander Hellemans, "The History of Science and Technology: A Browser's Guide to the Great Discoveries, Inventions, and the People Who Made Them from the Dawn of Time to Today". ISBN 0-618-22123-9
  • P. Mauskopf et al.,astro-ph/9911444, Astrophys. J. 536 (2000) L59-L62.
  • A. Melchiorri et al.,astro-ph/9911445, Astrophys. J. 536 (2000) L63-L66.
  • P. de Bernardis et al., astro-ph/0004404, Nature 404 (2000) 955-959.
  • A. Readhead et al., Polarization observations with the Cosmic Background Imager, Science 306 (2004), 836-844.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.