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Cited by 227Advanced Frequency and Time StandardsRelativity and Gravitational TheoryNetwork Time Synchronization Technologies

Test of Special Relativity Using a Fiber Network of Optical Clocks

Open access
Delva, P., Lodewyck, J., Bilicki, S., Bookjans, E., Vallet, G., Le Targat, R., Pottie, P.-E., Guerlin, C. +23 more·2017·Physical Review Letters
DOI 10.1103/physrevlett.118.221102
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Abstract

Phase compensated optical fiber links enable high accuracy atomic clocks separated by thousands of kilometers to be compared with unprecedented statistical resolution. By searching for a daily variation of the frequency difference between four strontium optical lattice clocks in different locations throughout Europe connected by such links, we improve upon previous tests of time dilation predicted by special relativity. We obtain a constraint on the Robertson-Mansouri-Sexl parameter |α|≲1.1×10^{-8}, quantifying a violation of time dilation, thus improving by a factor of around 2 the best known constraint obtained with Ives-Stilwell type experiments, and by 2 orders of magnitude the best constraint obtained by comparing atomic clocks. This work is the first of a new generation of tests of fundamental physics using optical clocks and fiber links. As clocks improve, and as fiber links are routinely operated, we expect that the tests initiated in this Letter will improve by orders of magnitude in the near future.

AI snapshot

Written from the paper’s full text.

TL;DR

The paper searches for a daily variation in the frequency difference between four strontium optical lattice clocks in France, Germany, and the United Kingdom connected by phase-compensated fiber links, as a test of time dilation in special relativity. It constrains the Robertson-Mansouri-Sexl Lorentz-invariance-violating parameter to \(|\alpha| \lesssim 1.1 \times 10^{-8}\), improving the best Ives-Stilwell constraint by about a factor of 2 and the best atomic-clock constraint by 2 orders of magnitude.

Key findings

  • The combined NPL-SYRTE fit gives \(\alpha_C = (-2.83 \pm 6.19) \times 10^{-8}\); the PTB-SYRTE fit gives \(\alpha_D = (-0.38 \pm 1.06) \times 10^{-8}\).
  • The final bound is \(|\alpha| \lesssim 1.1 \times 10^{-8}\), improving the best previous Ives-Stilwell-type constraint by around a factor of 2 and the best atomic-clock comparison constraint by 2 orders of magnitude.
  • In the PTB-SYRTE comparison, a significant temperature effect on the frequency comparison was found at the order of \(10^{-16}\,\mathrm{K}^{-1}\), with a lag of around 4.8 h; the bias on \(\alpha\) is \(-0.93 \times 10^{-8}\) if tides are not taken into account.
  • The NPL-SYRTE comparisons did not show significant systematic effects above the noise level, and a simulated temperature model using PTB-SYRTE parameters produced no signal above noise for NPL-SYRTE.

Methods

  • Design: compare four Sr optical lattice clocks—two at LNE-SYRTE in France, one at PTB in Germany, and one at NPL in the United Kingdom—connected by phase-compensated optical fiber links, and search for a sidereal-day variation in the relative frequency difference predicted by the Robertson-Mansouri-Sexl framework.
  • Data: NPL-SYRTE comparison from June 10–15, 2016, with about 60 h of data between SYRTE’s Sr2 and SrB clocks and NPL’s Sr clock; PTB-SYRTE comparison from June 4–24, 2015, with about 150 h of data between SYRTE’s Sr2 clock and PTB’s stationary Sr clock.
  • Analysis: fit models including the Lorentz-invariance-violating term \(2\alpha c^{-2}\vec{w}\cdot[\vec{v}_{\mathrm{SYRTE}}(t)-\vec{v}_{\mathrm{other}}(t)]\), using an affine invariant Markov Chain Monte Carlo ensemble sampler with \(10^5\) points and a nondiagonal covariance matrix; for PTB-SYRTE, a temperature model for the SYRTE clock room was included. The preferred frame is taken as the CMB rest frame, with \(w \simeq 340\,\mathrm{km\,s^{-1}}\) in June 2015 and 2016.

Limitations

  • The paper states that the RMS framework is purely kinematical and the results cannot be simply mapped to dynamical frameworks such as the standard model extension or dark matter models.
  • The paper states that the temperature effect on the PTB-SYRTE comparison is not yet fully understood, and that the lag \(\delta t_{\mathrm{SYRTE}}\) is not well constrained and its distribution is non-Gaussian.
  • The paper states that combining data sets A, B, and D gives no improvement on the uncertainty because the absolute bias in combination C is larger than the uncertainty from data set D; the text also makes evident that the test relies on limited-duration comparisons and technical noise sources.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1103/physrevlett.118.221102

Cites

41 of 41 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 23 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    The power spectral density distribution of the raw data shows a significant peak at a frequency of 1 day^-1, which is around the frequency of the Lorentz-invariance-violating signal.

    “Indeed, the power spectral density distribution of the raw data shows a significant peak at a frequency of 1 day -1 , which is around the frequency of the LI violating signal.”
    Quote in the paperSubstantial claim
  • Findingown data

    The bias of the parameter |alpha| is below the parameter uncertainty: alpha_D = (-0.38 +/- 1.06) x 10^-8.

    “The bias of the parameter jαj is below the parameter uncertainty: α D ¼ ð-0.38 Æ 1.06Þ × 10 -8 :ð11Þ”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The Robertson-Mansouri-Sexl framework assumes the existence of a preferred frame Sigma where light propagates rectilinearly and isotropically in free space with constant speed c.
    • The authors state this as an assumption: The preferred frame is taken as the rest frame of the cosmological microwave background (CMB).
  • Findingown data

    The constraint improves by 2 orders of magnitude the best constraint obtained by comparing atomic clocks.

    “and by 2 orders of magnitude the best constraint obtained by comparing atomic clocks.”
    Quote in the paperSubstantial claim
  • Findingown data

    By using clock comparisons between four optical clocks at NPL, PTB, and SYRTE, linked by an optical fiber network, the work puts a more stringent bound on the Lorentz-invariance-violating parameter alpha of the RMS framework.

    “In conclusion, by using clock comparisons between four optical clocks at NPL (United Kingdom), PTB (Germany), and SYRTE (France), linked by a leading-edge optical fiber network, we are able to put a more stringent bound on the LI violating parameter α of the RMS framework.”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The Robertson-Mansouri-Sexl framework assumes the existence of a preferred frame Sigma where light propagates rectilinearly and isotropically in free space with constant speed c.
    • The authors state this as an assumption: The preferred frame is taken as the rest frame of the cosmological microwave background (CMB).
  • Findingown data

    The constraint on the Robertson-Mansouri-Sexl parameter is |alpha| <~ 1.1 x 10^-8.

    “We obtain a constraint on the Robertson-Mansouri-Sexl parameter jαj ≲ 1.1 × 10 -8 , quantifying a violation of time dilation”
    Quote in the paperSubstantial claim
    • The authors state this as an assumption: The Robertson-Mansouri-Sexl framework assumes the existence of a preferred frame Sigma where light propagates rectilinearly and isotropically in free space with constant speed c.
    • The authors state this as an assumption: The preferred frame is taken as the rest frame of the cosmological microwave background (CMB).
  • May combine two claims. 18
  • Classified as probably not a substantial claim. 16
  • The quote only partly states this claim. 1

  • May combine two claims.

    Findingnone given

    The lag delta_t_SYRTE is not well constrained and its distribution is non-Gaussian; however, this does not affect the Gaussianity of the other parameters.

    “The lag δt SYRTE is not well constrained and its distribution is non-Gaussian.However, this does not affect the Gaussianity of the other parameters.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The correlations between the parameters are of the order or below 0.2.

    “The correlations between the parameters are of the order or below 0.2.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The frequency instability of the fractional frequency difference between SYRTE and NPL is solely limited by the performances of the clocks, as the fiber link between SYRTE and NPL shows a fractional frequency instability of 1 x 10^-18 at 1000 s.

    “This frequency instability is solely limited by the performances of the clocks, as the fiber link between SYRTE and NPL shows a fractional frequency instability of 1 × 10 -18 at 1000 s.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    A significant variation was found at 1 day^-1 frequency in the local SYRTE comparison, while the comparison at PTB did not show any significant variation at this frequency.

    “A significant variation was found at 1 day -1 frequency in the local SYRTE comparison, while the comparison at PTB did not show any significant variation at this frequency.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The correlations between the parameter alpha and the parameters ybar_Sr2_PTB-SYRTE, delta_t_SYRTE, and alpha_SYRTE_T are, respectively, -0.48, 0.44, and 0.30; these correlations slightly degrade the uncertainty on the determination of alpha.

    “The correlations between the parameter α and the parameters ȳSr2 PTB-SYRTE , δt SYRTE , and α SYRTE T are, respectively, -0.48, 0.44, and 0.30.These correlations slightly degrade the uncertainty on the determination of α.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    None of the other temperature series (SYRTE exterior, PTB exterior, PTB clock room, PTB clock laser room, PTB comb room) are able to explain the residual signal, leading to biases in alpha ranging from 2 sigma up to 5.5 sigma.

    “None of them are able to explain the residual signal, leading for the series (i-v) to biases in the parameter α ranging from 2σ up to 5.5σ”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingcitation

    During the considered dates of clock comparisons, peak-to-peak fractional frequency variations up to 1.3 x 10^-17 between PTB and SYRTE, and up to 5 x 10^-18 between NPL and SYRTE, are due to variations of the gravity potential induced by tides.

    “During the considered dates of clock comparisons, peak-topeak fractional frequency variations up to 1.3 × 10 -17 between PTB and SYRTE, and up to 5 × 10 -18 between NPL and SYRTE are due to variations of the gravity potential induced by tides.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [28] source

      Not checked in the free run.

  • The quote only partly states this claim.

    Findingown data

    The Allan deviation of the fractional frequency difference between SYRTE's clocks Sr2 and SrB and NPL's Sr clock is flat up to around 10 s averaging time.

    “As can be seen in Fig. 1, the Allan deviation is flat up to around 10 s averaging time.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Findingown data

    The bias found for the parameter alpha is -0.93 x 10^-8 if tides are not taken into account.

    “It is interesting to note that the bias found for the parameter α is -0.93 × 10 -8 if tides are not taken into account.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Findingnone given

    In the short term the laser probing the narrow transition is not yet locked to the atoms; therefore, the flicker floor of the free running laser is visible.

    “Indeed, in the short term the laser probing the narrow transition is not yet locked to the atoms; therefore, the flicker floor of the free running laser is visible.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    The detailed analysis of the PTB-SYRTE data shows a significant effect of temperature on the frequency comparison of the order of 10^-16 K^-1, with a lag of around 4.8 h.

    “It shows a significant effect of the temperature on the frequency comparison of the order of 10 -16 K -1 , with a lag of around 4.8 h.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationcitation

    One major limitation of the RMS framework is that it is purely kinematical, and the results cannot be simply mapped to dynamical frameworks.

    “As noted in Ref. [14], one major limitation of the RMS framework is that it is purely kinematical, and our results cannot be simply mapped to dynamical frameworks.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [14] source

      Not checked in the free run.

    • The authors state this as an assumption: The Robertson-Mansouri-Sexl framework assumes the existence of a preferred frame Sigma where light propagates rectilinearly and isotropically in free space with constant speed c.

  • May combine two claims.

    Interpretationcitation

    The second term of Eq. (6) is constant and, considering an upper bound of 2 x 10^-8 on alpha, is lower than 4 x 10^-20, which is significantly below the accuracy of the clocks; therefore it is not taken into account in the model.

    “The second term of Eq. ( 6) is constant, and, considering an upper bound of 2 × 10 -8 on the parameter α [17], is lower than 4 × 10 -20 , which is significantly below the accuracy of the clocks.Therefore we do not take it into account in our model.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [17] source

      Not checked in the free run.

    • The authors state this as an assumption: The Robertson-Mansouri-Sexl framework assumes the existence of a preferred frame Sigma where light propagates rectilinearly and isotropically in free space with constant speed c.

  • May combine two claims.

    Interpretationown data

    Q0 for the PTB-SYRTE link is more than twice the value for the NPL-SYRTE link, such that it is more sensitive to a violation of Lorentz invariance.

    “Note that Q 0 for the PTB-SYRTE link is more than twice the value for the NPL-SYRTE link such that it is more sensitive to a violation of LI.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationnone given

    The bound on alpha is purely limited by technical noise sources on the clock systems, which will improve in future comparisons.

    “Moreover, this bound is purely limited by technical noise sources on the clock systems, which will improve in future comparisons.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    The propagation noise in the fibers is actively compensated.

    “The propagation noise in the fibers is actively compensated.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A limit of |alpha| <= 8.4 x 10^-8 was found using 7Li+ ions prepared in a storage ring to 6.4% and 3.0% of the speed of light.

    “A limit of jαj ≤ 8.4 × 10 -8 was found using 7 Li þ ions prepared in a storage ring to 6.4% and 3.0% of the speed of light [16].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [16] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    The frequency counters at NPL, LPL, and SYRTE are synchronized to UTC(NPL), GPS time, and UTC(OP), respectively, with an accuracy well below 1 ms.

    “The frequency counters at NPL, LPL, and SYRTE are synchronized to UTC(NPL), GPS time, and UTC(OP), respectively, with an accuracy well below 1 ms.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The Robertson-Mansouri-Sexl (RMS) kinematical framework contains only three parameters.

    “In this Letter we use the Robertson-Mansouri-Sexl (RMS) kinematical framework [10][11][12][13] that contains only three parameters.”
    Quote in the paperNot a substantial claim0 of 3 sources checked
    • cites [10] source

      Not checked in the free run.

    • cites [11] source

      Not checked in the free run.

    • cites [12] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    For the combined data set C the correlation between both data sets is also taken into account in the covariance matrix.

    “For the combined data set C the correlation between both data sets is also taken into account in the covariance matrix.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    A simulated sinusoid with a 1 day period leads to a complete degeneracy of all parameters with no unique solution, showing that the residual effect cannot be well represented by a simple sinusoidal model.

    “and for (vi) to a complete degeneracy of all parameters with no unique solution, which shows that the residual effect cannot be well represented by a simple sinusoidal model, as parameters are completely degenerated with parameters from the LI violating model.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    When neglecting higher order RMS parameters, the constraint on the Lorentz-invariance-violating parameter alpha from Ref. [17] is |alpha| <~ 2.0 x 10^-8.

    “When neglecting higher order RMS parameters, the constraint on the LI violating parameter is jαj ≲ 2.0 × 10 -8 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [17] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Comparing resonance frequencies of optical clocks has led to new tests of fundamental physics, such as bounding the time variation of fundamental constants.

    “Thanks to these unparalleled performances, comparing the resonance frequencies of optical clocks has led to new tests of fundamental physics, such as bounding the time variation of fundamental constants [7,8].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [7] source

      Not checked in the free run.

    • cites [8] source

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    Although the 1 day^-1 signal could be interpreted as a violation of Lorentz invariance, a detailed analysis shows that this effect is probably due to temperature variations in the SYRTE clock laboratory.

    “Although this signal could be interpreted as a violation of LI, a detailed analysis shows that this effect is probably due to temperature variations in the SYRTE clock laboratory.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The temporal correlation is taken into account in the MCMC method fit by using a nondiagonal covariance matrix.

    “This temporal correlation is taken into account in the MCMC method fit by using a nondiagonal covariance matrix.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    The connection between distant optical clocks achieved with phase-compensated optical fibers allows an unprecedented level of statistical resolution for comparison of remote atomic clocks, making such a test possible for the first time.

    “The connection between these clocks, achieved with phase-compensated optical fibers, allows for an unprecedented level of statistical resolution for the comparison of remote atomic clocks [9], making such a test possible for the first time.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [9] source

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductreasoning

    The mean frequency offsets were removed from each comparison data subset because the analysis looks only for daily variations.

    “The mean frequency offsets were removed from each comparison data subset as we are looking only for daily variations.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The relative frequency difference y_NPL-SYRTE between the NPL Sr clock and the SYRTE Sr clock is corrected from the term Delta_cl.

    “The relative frequency difference y NPL-SYRTE between the NPL Sr clock and the SYRTE Sr clock is corrected from the term Δ cl .”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    First-order tests in w/c based on comparison of clocks gave the best constraints on the Lorentz-invariance-violating parameter alpha until recently, with e.g. |alpha| <= 10^-6 obtained by comparing atomic clocks onboard GPS satellites with ground atomic clocks.

    “Until recently, they gave the best constraints on the LI violating parameter α (see Ref. [14] for a review) with, e.g., jαj ≤ 10 -6 obtained by comparing atomic clocks' onboard GPS satellites with ground atomic clocks [15].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [14] source

      Not checked in the free run.

    • cites [15] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable), S3 (load-bearing).

    Interpretationnone given

    This work is the first of a new generation of tests of fundamental physics using optical clocks and fiber links.

    “This work is the first of a new generation of tests of fundamental physics using optical clocks and fiber links.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Optical clocks reach systematic uncertainties of a few 10^-18, which can be resolved after a few hours of measurement with optical lattice clocks based on trapped neutral atoms.

    “They reach systematic uncertainties of a few 10 -18 , which can be resolved after a mere few hours of measurement with optical lattice clocks based on trapped neutral atoms [2][3][4][5][6].”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [2] source

      Not checked in the free run.

    • cites [3] source

      Not checked in the free run.

    • cites [4] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The three classical Lorentz-invariance tests (Michelson-Morley, Kennedy-Thorndike, and Ives-Stillwell) are second-order tests because the Lorentz-invariance-violating signal depends on w^2/c^2.

    “The three classical LI tests are the Michelson-Morley, Kennedy-Thorndike, and Ives-Stillwell experiments [10]; they are second-order tests as the LI violating signal depends on w 2 =c 2 [13].”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [10] source

      Not checked in the free run.

    • cites [13] source

      Not checked in the free run.

32 of 32

  • The authors state this as an assumption.

    The Robertson-Mansouri-Sexl framework assumes the existence of a preferred frame Sigma where light propagates rectilinearly and isotropically in free space with constant speed c.

    “It assumes the existence of a preferred frame Σ where light propagates rectilinearly and isotropically in free space with constant speed c.”

  • The authors state this as an assumption.

    The preferred frame is taken as the rest frame of the cosmological microwave background (CMB).

    “⃗w is the velocity of the Earth with respect to a preferred frame, taken as the rest frame of the cosmological microwave background (CMB).”

  • The authors state this as an assumption.

    The terrestrial coordinates of the clocks are considered constant.

    “They are obtained by transforming the terrestrial coordinates of the clocks, considered as constant, with the SOFA routines [29].”
3 of 3

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Recent analysis of optical clock comparisons have included temporal variations.

    “Recent analysis of optical clock comparisons have included temporal variations [130, 131].”

    From Chronometric Geodesy: Methods and Applications (2019) · cites this paper as [131]

  • Recent analysis of optical clock comparisons already included temporal variations.

    “Recent analysis of optical clock comparisons already included temporal variations [130, 131].”

    From Chronometric Geodesy: Methods and Applications (2019) · cites this paper as [131]

  • These optical clocks can be used to explore geophysical phenomena, detect gravitational waves, test general relativity and search for dark matter.

    “These optical clocks can further be used to explore geophysical phenomena 10 , detect gravitational waves 11 , test general relativity 12 and search for dark matter 13-17 .”

    From Atomic clock performance enabling geodesy below the centimetre level (2018) · cites this paper as [12]

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Authors
Delva, P., Lodewyck, J., Bilicki, S., Bookjans, E., Vallet, G., Le Targat, R., Pottie, P.-E., Guerlin, C., Meynadier, F., Le Poncin-Lafitte, C., Lopez, O., Amy-Klein, A., Lee, W.-K., Quintin, N., Lisdat, C., Al-Masoudi, A., Dörscher, S., Grebing, C., Grosche, G., Kuhl, A., Raupach, S., Sterr, U., Hill, I. R., Hobson, R., Bowden, W., Kronjäger, J., Marra, G., Rolland, A., Baynes, F. N., Margolis, H. S., & Gill, P.
Affiliations
  • Centre National de la Recherche Scientifique (FR)
  • Physikalisch-Technische Bundesanstalt (DE)
  • National Physical Laboratory (GB)
ORCID
Venue
Physical Review Letters
Publisher
American Physical Society (APS)
Published
2017-06-02
Volume
118
Issue
22
Pages
221102-221102
ISSN
  • 0031-9007 (ISSN-L)
  • 1079-7114
DOI
10.1103/physrevlett.118.221102
OpenAlex
W2595844539
Cited by
227
References
41
Citations by year
2026: 14 · 2025: 21 · 2024: 19 · 2023: 26 · 2022: 27 · 2021: 19 · 2020: 33 · 2019: 31 · 2018: 26 · 2017: 11
FWCI
13.68
Type
journal article
Language
en
Open access
Licence
link.aps.org/licenses/aps-default-license (vor)
Locations
  • Physical Review Letters (publishedVersion)
  • PubMed (publishedVersion)
  • arXiv (Cornell University) (submittedVersion)
  • HAL (submittedVersion, other-oa)
  • HAL (submittedVersion)
  • Adelaide Research & Scholarship (AR&S) (University of Adelaide) (submittedVersion)
  • arXiv (Cornell University)
Funders
  • Korea Research Institute of Standards and Science (16011007)
  • National Research Council of Science and Technology (CAP-15-08-KRISS)
  • Seventh Framework Programme (605243)
  • Horizon 2020 Framework Programme
  • Agence Nationale de la Recherche
  • Institut National des Sciences de l’Univers, Centre National de la Recherche Scientifique
  • Centre National d’Etudes Spatiales
  • Conseil Régional, Île-de-France
  • Deutsche Forschungsgemeinschaft (RTG 1729)
  • European Metrology Research Programme
  • European Metrology Programme for Innovation and Research (SIB02 NEAT-FT, SIB55 ITOC, 15SIB05 OFTEN, 15SIB03 OC18)
  • UK National Measurement System: Quantum, Electromagnetics and Time Programme
Topics
  • Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Advanced Frequency and Time Standards
  • Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Relativity and Gravitational Theory
  • Physical Sciences › Computer Science › Computer Networks and Communications › Network Time Synchronization Technologies
Keywords
special relativity tests, time dilation, strontium optical lattice clock, optical fiber links, phase compensation, clock distribution

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