String Theory, Cosmology and Varying Constants

  • Thibault Damour


In string theory the coupling ‘constants’ appearing in the low-energy effective Lagrangian are determined by the vacuum expectation values of some (a priori) massless scalar fields (dilaton, moduli). This naturally leads one to expect a correlated variation of all the coupling constants, and an associated violation of the equivalence principle. We review some string-inspired theoretical models which incorporate such a spacetime variation of coupling constants while remaining naturally compatible both with phenomenological constraints coming from geochemical data (Oklo; Rhenium decay) and with present equivalence principle tests. Barring a very unnatural fine-tuning of parameters, a variation of the fine-structure constant as large as that recently ‘observed’ by Webb et al. in quasar absorption spectra appears to be incompatible with these phenomenological constraints. Independently of any model, it is emphasized that the best experimental probe of varying constants are high-precision tests of the universality of free fall, such as MICROSCOPE and STEP.


Dark Matter String Theory Equivalence Principle Vacuum Expectation Value Cosmological Evolution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Barrow, J.D.: gr-qc/0209080.Google Scholar
  2. Bekenstein, J.D.: 1982, Phys. Rev. D 25, 1527.MathSciNetADSCrossRefGoogle Scholar
  3. Damour, T., Gibbons, G.W. and Gundlach, C.: 1990, Phys. Rev. Lett 64, 123.ADSCrossRefGoogle Scholar
  4. Damour, T. and Nordtvedt, K.: 1993, Phys. Rev. Lett 70, 2217;ADSCrossRefGoogle Scholar
  5. Damour, T. and Nordtvedt, K.: 1993, Phys. Rev. D 48, 3436.MathSciNetADSCrossRefGoogle Scholar
  6. Damour, T. and Polyakov, A.M.: 1994, Nucl. Phys. B 423, 532;MathSciNetADSzbMATHCrossRefGoogle Scholar
  7. Damour, T. and Polyakov, A.M.: 1994, Gen. Rel. Gray 26, 1171.MathSciNetADSCrossRefGoogle Scholar
  8. Damour, T. and Vilenkin, A.: 1996, Phys. Rev. D 53, 2981.ADSCrossRefGoogle Scholar
  9. Damour, T. and Dyson, F.: 1996, Nucl. Phys. B 480, 37.ADSCrossRefGoogle Scholar
  10. Damour, T.: 2000, in: J. Tran Than Van et al. (ed.) Gravitational Waves and Experimental Gravity,World Publishers, Hanoi, pp. 357–363; gr-qc/9904032.Google Scholar
  11. Damour, T., Piazza, F. and Veneziano, G.: 2002a, Phys. Rev. Leu 89, 08 1601.Google Scholar
  12. Damour, T., Piazza, F. and Veneziano, G.: 2002b, Phys. Rev. D 66, 046007.Google Scholar
  13. Fujii, Y. et al.: 2000, Nucl. Phys B573, 377.ADSCrossRefGoogle Scholar
  14. Gasperini, M., Piazza, F. and Veneziano, G.: 2002, Phys. Rev. D 65, 023508.Google Scholar
  15. Linde, A.: 1990, Particle Physics and Inflationary Cosmology, Harwood, Chur.Google Scholar
  16. Murphy, M. et al.: 2001, MNRAS 327, 1208.ADSCrossRefGoogle Scholar
  17. Olive, K. et al.: 2002, Phys. Rev. D 66, 045022.Google Scholar
  18. Olive, K.A. and Pospelov, M.: 2002, Phys. Rev. D 65, 85044.ADSCrossRefGoogle Scholar
  19. Perlmutter, S. et al.: 1999, Astrophys. J 517, 565.ADSCrossRefGoogle Scholar
  20. Prestage, J.D., Tjoelker, R.L. and Maleki, L.: 1995, Phys. Rev. Lett 74, 3511.ADSCrossRefGoogle Scholar
  21. Review of Particle Physics: 2002a, The review of experimental tests of gravitational theory (Chapter 17), Phys. Rev. D 66, 010001, available on
  22. Review of Particle Physics: 2002b, The review of global cosmological parameters (Chapter 20), Phys. Rev. D 66, 010001, available on
  23. Riess, A. et al.: 1998, Astronom. J 116, 1009.ADSCrossRefGoogle Scholar
  24. Salomon, C. et al.: 2001, in: E. Arimondo and M. Inguscio (eds.), Cold Atom Clocks on Earth and in Space, Proceedings of the 17 th Int. Conf. on Atomic Physics, World Scientific, Singapore, p. 23.Google Scholar
  25. Sandvik, H.B., Barrow, J.D. and Magueijo, J.: 2002, Phys. Rev. Lett 88, 03 1302.Google Scholar
  26. Sortais, Y. et al.: 2001, Physica Scripta 95, 50.CrossRefGoogle Scholar
  27. Su, Y. et al.: 1994, Phys. Rev. D 50, 3614.ADSCrossRefGoogle Scholar
  28. Taylor, T.R. and Veneziano, G.: 1988, Phys. Lett. B 213, 450.ADSCrossRefGoogle Scholar
  29. Touboul, P. et al.: 2001, C.R. Acad. Sci. Paris 2 (série IV) 1271.Google Scholar
  30. Veneziano, G.: 2002, J. High Energy Phys 06, 051.MathSciNetADSCrossRefGoogle Scholar
  31. Webb, J.K. et al.: 2001, Phys. Rev. Lett 87, 09 1301.Google Scholar
  32. Will, C.M.: 2001, Living Rev. Rel 4, 4.MathSciNetGoogle Scholar
  33. Witten, E.: 1984, Phys. Lett. B 149, 351.MathSciNetADSCrossRefGoogle Scholar
  34. Worden, P.W.: 1995, in: R.T. Jantzen and G. MacKeiser (eds.), Proc. 7th Marcel Grossmann Meeting on General Relativity, World Scientific, Singapore, pp. 1569–1573.Google Scholar
  35. Uzan, J.P.: Rev. Mod. Phys,to appear; hep-ph/0205340.Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2003

Authors and Affiliations

  • Thibault Damour
    • 1
  1. 1.Institut des Hautes Etudes ScientifiquesBures-sur-YvetteFrance

Personalised recommendations