Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

A null test of general relativity based on a long-term comparison of atomic transition frequencies

Nature Physics volume 14, pages 822–826 (2018)Cite this article

Subjects

Abstract

The local position invariance principle of general relativity stipulates that non-gravitational experiments should give outcomes that are independent of the position and orientation of the reference frames in which they have been performed. Here, we study the change in the rates of clocks on Earth with the spatial change of the solar potential, constraining the variation of a non-gravitational interaction—the hyperfine splitting in hydrogen and caesium atoms—to β = (2.2 ± 2.5) × 10−7, a factor of two improvement over previous estimates. Our result is based on the comparison between the long-term fractional frequency variation of four hydrogen masers that are part of an ensemble of clocks comprising the National Institute of Standards and Technology, Boulder, and the fractional frequencies of primary frequency standards operated by leading metrology laboratories in the United States, France, Germany, Italy and the United Kingdom over a period of more than 14 years. Using our results together with the previous best estimates of β, we impose strict limits on the variation of fundamental constants, resulting in a test of general relativity with an unprecedented level of precision.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Position of Earth and Jupiter on modified Julian day (MJD) 56263 (2 December 2012).
Fig. 2: Frequency shifts of H and Cs for maser S3 for MJD 51508 (11 November 1999) to MJD 56959 (29 October 2014).
Fig. 3: Addressing the drift in the H maser with fitting functions.

References

  1. Einstein, A. The Collected Papers of Albert Einstein, Volume 6: The Berlin Years: Writings, 1914–1917 (Princeton Univ. Press, Princeton, NJ, 1996).

  2. DeMille, D., Doyle, J. M. & Sushkov, A. O. Probing the frontiers of particle physics with tabletop-scale experiments. Science 357, 990–994 (2017).

    Article  ADS  Google Scholar 

  3. Will, C. M. The confrontation between general relativity and experiment. Living Rev. Relativ 9, 3 (2014).

    Article  ADS  MATH  Google Scholar 

  4. Dicke, R. H. Experimental Relativity: Lectures delivered at Les Houches, 1963; Relativity, Groups and Topolo gy (eds DeWitt, C. and DeWitt, B.) (Gordon & Breach, New York, NY, 1964).

  5. Sullivan, D. B. Time and frequency measurement at NIST: the first 100 years. In Proc. 2001 IEEE International Frequency Control Symposium, Cat. No. 01CH37218, 4–17 (IEEE, Piscataway, NJ, 2001).

  6. Ashby, N. et al. Testing local position invariance with four cesium-fountain primary frequency standards and four NIST hydrogen masers. Phys. Rev. Lett. 98, 070802 (2007).

    Article  ADS  Google Scholar 

  7. Levi, F. et al. Accuracy evaluation of ITCsF2: a nitrogen cooled caesium fountain. Metrologia 51, 270–284 (2014).

    Article  ADS  Google Scholar 

  8. Jefferts, S. R. et al. Accuracy evaluation of NIST-F1. Metrologia 39, 321–336 (2003).

    Article  ADS  Google Scholar 

  9. Weyers, S., Hubner, U., Schroder, R., Tamm, C. & Bauch, A. Uncertainty evaluation of the atomic caesium fountain CSF1 of the PTB. Metrologia 38, 343–352 (2001).

    Article  ADS  Google Scholar 

  10. Gerginov, V. et al. Uncertainty evaluation of the caesium fountain clock PTB-CSF2. Metrologia 47, 65–79 (2010).

    Article  ADS  Google Scholar 

  11. Szymaniec, K. et al. NPL Cs fountain frequency standards and the quest for the ultimate accuracy. J. Phys. Conf. Ser. 723, 012003 (2016).

    Article  Google Scholar 

  12. Guéna, J. et al. Progress in atomic fountains at LNE-SYRTE. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 59, 391–410 (2012).

    Article  Google Scholar 

  13. Reports of Evaluation of Primary Frequency Standards (BIPM, accessed 14 March 2017); http://www.bipm.org/en/bipm-services/timescales/time-ftp/data.html

  14. Folkner, W. M., Williams, J. G., Boggs, D. H., Park, R. S. & Kuchynka, P. The Planetary and Lunar Ephemerides DE430 and DE431 InterPlanetary Network Progress Report 42–196 (IPN, 2014).

  15. Guéna, J. et al. Improved tests of local position invariance using Rb87 and Cs133 fountains. Phys. Rev. Lett. 109, 080801 (2012).

    Article  ADS  Google Scholar 

  16. Peil, S., Crane, S., Hanssen, J. L., Swanson, T. B. & Ekstrom, C. R. Tests of local position invariance using continuously running atomic clocks. Phys. Rev. A 87, 010102(R) (2013).

    Article  ADS  Google Scholar 

  17. Uzan, J. The fundamental constants and their variation: observational and theoretical status. Rev. Mod. Phys. 75, 403–455 (2003).

    Article  ADS  MathSciNet  MATH  Google Scholar 

  18. Fischer, M. et al. New limits on the drift of fundamental constants from laboratory measurements. Phys. Rev. Lett. 92, 230802 (2004).

    Article  ADS  Google Scholar 

  19. Flambaum, V. V. & Tedesco, A. F. Dependence of nuclear magnetic moments on quark masses and limits on temporal variation of fundamental constants from atomic clock experiments. Phys. Rev. C 73, 055501 (2006).

    Article  ADS  Google Scholar 

  20. Dinh, T. H., Dunning, A., Dzuba, V. A. & Flambaum, V. V. Sensitivity of hyperfine structure to nuclear radius and quark mass variation. Phys. Rev. A 79, 054102 (2009).

    Article  ADS  Google Scholar 

  21. Dzuba, V. A. & Flambaum, V. V. Limits on gravitational Einstein equivalence principle violation from monitoring atomic clock frequencies during a year. Phys. Rev. D 95, 015019 (2017).

    Article  ADS  Google Scholar 

  22. Godun, R. M. et al. Frequency ratio of two optical clock transitions in 171Yb+ and constraints on the time variation of fundamental constants. Phys. Rev. Lett. 113, 210801 (2014).

    Article  ADS  Google Scholar 

  23. Huntemann, N. et al. Improved limit on a temporal variation of m p/m e from comparisons of Yb+ and Cs atomic clocks. Phys. Rev. Lett. 113, 210802 (2014).

    Article  ADS  Google Scholar 

  24. Ludlow, A. D., Boyd, M. M., Ye, J., Peik, E. & Schmidt, P. O. Optical atomic clocks. Rev. Mod. Phys. 87, 637–701 (2015).

    Article  ADS  Google Scholar 

  25. Lisdat, C. et al. A clock network for geodesy and fundamental science. Nat. Commun. 7, 12443 (2016).

    Article  ADS  Google Scholar 

  26. Nicholson, T. L. et al. Systematic evaluation of an atomic clock at 2 × 10−18 total uncertainty. Nat. Commun. 6, 6896 (2015).

    Article  Google Scholar 

  27. Schioppo, M. et al. Ultrastable optical clock with two cold-atom ensembles. Nat. Photon. 11, 48–52 (2017).

    Article  ADS  Google Scholar 

  28. Tobar, M. E. et al. Testing local position and fundamental constant invariance due to periodic gravitational and boost using long-term comparison of the SYRTE atomic fountains and H-masers. Phys. Rev. D 87, 122004 (2013).

    Article  ADS  Google Scholar 

  29. Parker, T. E., Jefferts, S. R., Heavner, T. P. & Donley, E. A. Operation of the NIST-F1 caesium fountain primary frequency standard with a maser ensemble, including the impact of frequency transfer noise. Metrologia 42, 423–430 (2005).

    Article  ADS  Google Scholar 

  30. Panfilo, G. & Parker, T. E. A theoretical and experimental analysis of frequency transfer uncertainty, including frequency transfer into TAI. Metrologia 47, 552–560 (2010).

    Article  ADS  Google Scholar 

  31. Turneaure, J. P., Will, C. M., Farrell, B. F., Mattison, E. M. & Vessot, R. F. C. Test of the principle of equivalence by a null gravitational red-shift experiment. Phys. Rev. D 27, 1705–1714 (1983).

    Article  ADS  Google Scholar 

  32. Godone, A., Novero, C. & Tavella, P. Null gravitational redshift experiment with nonidentical atomic clocks. Phys. Rev. D 51, 319–323 (1995).

    Article  ADS  Google Scholar 

  33. Heß, M. P. et al. The ACES mission: system development and test status. Acta Astronaut. 69, 929–938 (2011).

    Article  ADS  Google Scholar 

  34. Altschul, B. et al. Quantum tests of the Einstein equivalence principle with the STE-QUEST space mission. Adv. Space Res. 55, 501–524 (2015).

    Article  ADS  Google Scholar 

  35. Vessot, R. F. C. et al. Test of relativistic gravitation with a space-borne hydrogen maser. Phys. Rev. Lett. 45, 2081–2084 (1980).

    Article  ADS  Google Scholar 

  36. Parker, T. E. Environmental factors and hydrogen maser frequency stability. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 46, 745–751 (1999).

    Article  Google Scholar 

  37. Lewis, L. L. An introduction to frequency standards. Proc. IEEE 79, 927–935 (1991).

    Article  ADS  Google Scholar 

Download references

Acknowledgements

We acknowledge funding from NASA grant NNH12AT81I. We also thank the atomic standards group at NIST for maintaining the H masers and sharing the data. We thank E. Donley, S. Jefferts and C. Oates for providing valuable suggestions that have helped improve this paper. We thank J. Sherman and J. Ye for discussing the planned clock comparisons between NIST and JILA. This work is a contribution of NIST and is not subject to US copyright.

Author information

Authors and Affiliations

  1. National Institute of Standards and Technology, Boulder, CO, USA

    Neil Ashby, Thomas E. Parker & Bijunath R. Patla

  2. Department of Physics, University of Colorado, Boulder, CO, USA

    Neil Ashby

Authors
  1. Neil Ashby
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Thomas E. Parker
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Bijunath R. Patla
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

T.E.P. compiled data from BIPM and analysed maser versus primary frequency standard data. N.A. and B.R.P. carried out the data analysis and performed the calculations that were the basis of the main conclusions of this paper. B.R.P. wrote the manuscript with input from all of the authors, and all authors discussed the results and the conclusions.

Corresponding author

Correspondence to Bijunath R. Patla.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary notes, Supplementary Tables 1,2, Supplementary Figure 1 and references

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ashby, N., Parker, T.E. & Patla, B.R. A null test of general relativity based on a long-term comparison of atomic transition frequencies. Nature Phys 14, 822–826 (2018). https://doi.org/10.1038/s41567-018-0156-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41567-018-0156-2

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing