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Numerical testing of the Rare Earth Hypothesis using Monte Carlo realization techniques

Published online by Cambridge University Press:  24 February 2010

Duncan H. Forgan*
Affiliation:
Scottish Universities Physics Alliance (SUPA), Institute for Astronomy, University of Edinburgh, Royal Observatory Edinburgh, Blackford Hill, EdinburghEH9 3HJ, UK.
Ken Rice
Affiliation:
Scottish Universities Physics Alliance (SUPA), Institute for Astronomy, University of Edinburgh, Royal Observatory Edinburgh, Blackford Hill, EdinburghEH9 3HJ, UK.

Abstract

The Search for Extraterrestrial Intelligence (SETI) has thus far failed to provide a convincing detection of intelligent life. In the wake of this null signal, many ‘contact-pessimistic’ hypotheses have been formulated, the most famous of which is the Rare Earth Hypothesis. It postulates that although terrestrial planets may be common, the exact environmental conditions that Earth enjoys are rare, perhaps unique. As a result, simple microbial life may be common, but complex metazoans (and, hence, intelligence) will be rare. In this paper we use Monte Carlo realization techniques to investigate the Rare Earth Hypothesis, in particular the environmental criteria considered imperative to the existence of intelligence on Earth. By comparing with a less restrictive, more optimistic hypothesis, the data indicate that if the Rare Earth hypothesis is correct, intelligent civilization will indeed be relatively rare. Studying the separations of pairs of civilizations shows that most intelligent civilization pairs (ICPs) are unconnected: that is, they will not be able to exchange signals at lightspeed in the limited time that both are extant. However, the few ICPs that are connected are strongly connected, being able to participate in numerous exchanges of signals. This may provide encouragement for SETI researchers: although the Rare Earth Hypothesis is in general a contact-pessimistic hypothesis, it may be a ‘soft’ or ‘exclusive’ hypothesis, i.e. it may contain facets that are latently contact-optimistic.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2010

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References

Annis, J. (1999). J. Br. Interplanet. Soc. 52, 19.Google Scholar
Armitage, P.J. (2007). ApJ 665, 1381.CrossRefGoogle Scholar
Batygin, K. & Laughlin, G. (2008). ApJ 683, 1207.CrossRefGoogle Scholar
Bounamam, C., von Bloh, W. & Franck, S. (2007). Astrobiology 7, 745.CrossRefGoogle Scholar
Brin, G.D. (1983). Q. J. R. Astron. Soc. 24, 283.Google Scholar
Canfield, D.E. (2005). Ann. Rev. Earth Planet. Sci. 33, 1.CrossRefGoogle Scholar
Carr, M.H. et al. (1998). Nature 391, 363.CrossRefGoogle Scholar
Carter, B. (2008). Int. J. Astrobiol. 7, 177.CrossRefGoogle Scholar
Cavicchioli, R. (2002). Astrobiology 2, 281.CrossRefGoogle Scholar
Cirkovic, M.M. (2009). Serb. Astron. J. 178, 1.CrossRefGoogle Scholar
Cresswell, P. & Nelson, R.P. (2006). A&A 450, 833.Google Scholar
Diaz, B. & Schulze-Makuch, D. (2006). Astrobiology 6, 332.CrossRefGoogle Scholar
Ford, E.B. & Rasio, F.A. (2008). ApJ 686, 621.CrossRefGoogle Scholar
Forgan, D. (2009). Int. J. Astrobiol. 8, 121.CrossRefGoogle Scholar
Formisano, V., Atreya, S., Encrenaz, T., Ignatiev, N. & Giuranna, M. (2004). Science 306(5702), 1758.CrossRefGoogle Scholar
Hart, M.H. (1979). Icarus 37, 351.CrossRefGoogle Scholar
Horner, J. & Jones, B.W. (2008). Int. J. Astrobiol. 7, 251.CrossRefGoogle Scholar
Horner, J. & Jones, B.W. (2009). Int. J. Astrobiol. 8, 75.CrossRefGoogle Scholar
Horner, J., Jones, B.W. & Chambers, J. (2010). Int. J. Astrobiol. 9, 1.CrossRefGoogle Scholar
Ida, S. & Lin, D.N.C. (2008). ApJ 673, 487.CrossRefGoogle Scholar
Kasting, J.F., Whitmire, D.P. & Reynolds, R.T. (1993). Icarus 101, 108.CrossRefGoogle Scholar
Kipping, D.M., Fossey, S.J. & Campanella, G. (2009). On the detectability of habitable exomoons with Kepler-class photometry. Mon. Notices R. Astron. Soc. 400, 398405.CrossRefGoogle Scholar
Krasnopolsky, V.A., Maillard, J.P. & Owen, T.C. (2004). Icarus 172, 537.CrossRefGoogle Scholar
Lineweaver, C.H., Fenner, Y. & Gibson, B.K. (2004). Science 303, 59.CrossRefGoogle Scholar
Maccone, C. (2009). The statistical Drake equation. Acta Astronautica. Paper IAC-08-A4.1.4, 2008, IAC, Glasgow, Scotland, UK.Google Scholar
Ostlie, D.A. & Carroll, B.W. (1996). An Introduction to Modern Stellar Astrophysics. ISBN 0-201-59880-9.Google Scholar
Paardekooper, S.-J. and Papaloizou, J.C.B. (2008). A&A 485, 877.Google Scholar
Parkinson, C.D., Liang, M.-C., Hartman, H., Hansen, C.J., Tinetti, G., Meadows, V., Kirschvink, J.L. & Yung, Y.L. (2007). A&A 463, 353.Google Scholar
Prialnik, D. (2000). An Introduction to the Theory of Stellar Structure and Evolution. ISBN 052165937X, Cambridge University Press.Google Scholar
Raup, D.M. & Sepkoski, J.J. (1982). Science 215(4539), 1501.CrossRefGoogle Scholar
Raymond, S.N., Armitage, P.J. & Gorelick, N. (2009). ApJL 699, L88.CrossRefGoogle Scholar
Raymond, S.N., Mandell, A.M. & Sigurdsson, S. (2006). Science 313, 1413.CrossRefGoogle Scholar
Rocha-Pinto, H.J., Maciel, W.J., Scalo, J. & Flynn, C. (2000a). A&A 358, 850.Google Scholar
Rocha-Pinto, H.J., Scalo, J., Maciel, W.J. and Flynn, C. (2000b). A&A 358, 869.Google Scholar
Rolleston, W.R.J., Smartt, S.J., Dufton, P.L. and Ryans, R.S.I. (2000). A&A 363, 537.Google Scholar
Sartoretti, P. & Schneider, J. (1999). A&AS 134, 553.Google Scholar
Schröder, K.-P. & Connon Smith, R. (2008). Mon. Notices R. Astron. Soc. 386, 155.CrossRefGoogle Scholar
Spencer, J. & Grinspoon, D. (2007). Nature 445, 376.CrossRefGoogle Scholar
Spiegel, D.S., Menou, K. & Scharf, C.A. (2008). ApJ 681, 1609.CrossRefGoogle Scholar
Stofan, E.R. et al. (2007). Nature 445, 61.CrossRefGoogle Scholar
Vukotic, B. & Cirkovic, M.M. (2007). Serb. Astron. J. 175, 45.CrossRefGoogle Scholar
Vukotic, B. & Cirkovic, M.M. (2008). Serb. Astron. J. 176, 71.CrossRefGoogle Scholar
Waltham, D. (2004). Astrobiology 4, 460.CrossRefGoogle Scholar
Ward, P. & Brownlee, D. (2000). Rare Earth: Why Complex Life is Uncommon in the Universe. ISBN 0-387-98701-0, Copernicus Books (Springer).CrossRefGoogle Scholar
Williams, D.M. & Pollard, D. (2002). Int. J. Astrobiol. 1, 61.CrossRefGoogle Scholar
Wyatt, M.C., Clarke, C.J. & Greaves, J.S. (2007). Mon. Notices R. Astron. Soc. 380, 1737.CrossRefGoogle Scholar