The characterization of the universe as finely tuned suggests that the occurrence of
life
Life is a quality that distinguishes matter that has biological processes, such as Cell signaling, signaling and self-sustaining processes, from that which does not, and is defined by the capacity for Cell growth, growth, reaction to Stimu ...
in the
universe
The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. ...
is very sensitive to the values of certain fundamental physical constants and that the observed values are, for some reason, improbable. If the values of any of certain free parameters in contemporary physical theories had differed only slightly from those observed, the evolution of the universe would have proceeded very differently and life as it is understood may not have been possible.Gribbin. J and Rees. M, ''Cosmic Coincidences: Dark Matter, Mankind, and Anthropic Cosmology'' pp. 7, 269, 1989,
History
In 1913, the
chemist
A chemist (from Greek ''chÄ“m(Ãa)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe t ...
Lawrence Joseph Henderson
Lawrence Joseph Henderson (June 3, 1878, Lynn, Massachusetts – February 10, 1942, Cambridge, Massachusetts) was a physiologist, chemist, biologist, philosopher, and sociologist. He became one of the leading biochemists of the early 20th ce ...
wrote ''The Fitness of the Environment,'' one of the first books to explore fine tuning in the universe. Henderson discusses the importance of water and the environment to living things, pointing out that life depends entirely on earth's very specific environmental conditions, especially the prevalence and properties of water.
In 1961, physicist Robert H. Dicke claimed that certain forces in physics, such as
gravity
In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the stro ...
and
electromagnetism
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of ...
, must be perfectly fine-tuned for life to exist in the universe.
Fred Hoyle
Sir Fred Hoyle FRS (24 June 1915 – 20 August 2001) was an English astronomer who formulated the theory of stellar nucleosynthesis and was one of the authors of the influential B2FH paper. He also held controversial stances on other sci ...
also argued for a fine-tuned universe in his 1984 book ''The Intelligent Universe''. "The list of anthropic properties, apparent accidents of a non-biological nature without which carbon-based and hence human life could not exist, is large and impressive", Hoyle wrote.
Belief in the fine-tuned universe led to the expectation that the Large Hadron Collider would produce evidence of physics beyond the Standard Model, such as supersymmetry, but by 2012 it had not produced evidence for supersymmetry at the energy scales it was able to probe.
Motivation
Physicist
Paul Davies
Paul Charles William Davies (born 22 April 1946) is an English physicist, writer and broadcaster, a professor in Arizona State University and Director of BEYOND: Center for Fundamental Concepts in Science. He is affiliated with the Institute ...
has said, "There is now broad agreement among physicists and cosmologists that the Universe is in several respects ‘fine-tuned' for life". However, he continued, "the conclusion is not so much that the Universe is fine-tuned for life; rather it is fine-tuned for the building blocks and environments that life requires." He has also said that
John D. Barrow
John David Barrow (29 November 1952 – 26 September 2020) was an English cosmologist, theoretical physicist, and mathematician. He served as Gresham Professor of Geometry at Gresham College from 2008 to 2011. Barrow was also a writer of pop ...
(2003). ''The Constants of Nature'', Pantheon Books,
*
Bernard Carr
Bernard J. Carr is a British professor of mathematics and astronomy at Queen Mary University of London (QMUL).
His research interests include the early universe, dark matter, general relativity, primordial black holes, and the anthropic princip ...
Graham Priest
Graham Priest (born 1948) is Distinguished Professor of Philosophy at the CUNY Graduate Center, as well as a regular visitor at the University of Melbourne, where he was Boyce Gibson Professor of Philosophy and also at the University of St Andr ...
Paul Davies
Paul Charles William Davies (born 22 April 1946) is an English physicist, writer and broadcaster, a professor in Arizona State University and Director of BEYOND: Center for Fundamental Concepts in Science. He is affiliated with the Institute ...
Paul Davies
Paul Charles William Davies (born 22 April 1946) is an English physicist, writer and broadcaster, a professor in Arizona State University and Director of BEYOND: Center for Fundamental Concepts in Science. He is affiliated with the Institute ...
Alister McGrath
Alister Edgar McGrath (; born 1953) is a Northern Irish theologian, Anglican priest, intellectual historian, scientist, Christian apologist, and public intellectual. He currently holds the Andreas Idreos Professorship in Science and Religion i ...
(2009). ''A Fine-Tuned Universe: The Quest for God in Science and Theology'', Westminster John Knox Press, .
* Timothy J. McGrew, Lydia McGrew, Eric Vestrup (2001). "Probabilities and the Fine-Tuning Argument: A Sceptical View". ''Mind'' 110: 1027–37.
*
Simon Conway Morris
Simon Conway Morris (born 1951) is an English palaeontologist, evolutionary biologist, and astrobiologist known for his study of the fossils of the Burgess Shale and the Cambrian explosion. The results of these discoveries were celebrated in ...
(2003). ''Life's Solution: Inevitable Humans in a Lonely Universe''. Cambridge Univ. Press.
*
Martin Rees
Martin John Rees, Baron Rees of Ludlow One or more of the preceding sentences incorporates text from the royalsociety.org website where: (born 23 June 1942) is a British cosmologist and astrophysicist. He is the fifteenth Astronomer Royal, ...
(1999). ''Just Six Numbers'', HarperCollins Publishers, .
*
Victor J. Stenger
Victor John Stenger (; January 29, 1935 – August 25, 2014) was an American particle physicist, philosopher, author, and religious skeptic.
Following a career as a research scientist in the field of particle physics, Stenger was associated ...
Elliott Sober
Elliott R. Sober (born 6 June 1948) is Hans Reichenbach Professor and William F. Vilas Research Professor in the Department of Philosophy at University of Wisconsin–Madison. Sober is noted for his work in philosophy of biology and general phil ...