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Title: Testing Local Position Invariance with Four Cesium-Fountain Primary Frequency Standards and Four NIST Hydrogen Masers

Abstract

We report the most sensitive tests to date of the assumption of local position invariance (LPI) underlying general relativity, based on a 7 yr comparison of cesium and hydrogen atomic clocks (frequency standards). The latest results place an upper limit that is over 20 times smaller than the previous most sensitive tests; this is consistent with the null shift predicted by LPI. The result is based on precise comparisons of frequencies of four hydrogen masers maintained by NIST, with four independent Cs fountain clocks--one at NIST and three in Europe--as the Sun's gravitational potential at Earth's surface varies due to Earth's orbital eccentricity.

Authors:
; ; ; ; ;  [1];  [2];  [3]
  1. Department of Physics, University of Colorado, Boulder, Colorado 80309-0390 (United States)
  2. (United States)
  3. (Russian Federation)
Publication Date:
OSTI Identifier:
20955460
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 7; Other Information: DOI: 10.1103/PhysRevLett.98.070802; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMIC CLOCKS; CESIUM; GENERAL RELATIVITY THEORY; HYDROGEN; MASERS

Citation Formats

Ashby, N., Heavner, T. P., Jefferts, S. R., Parker, T. E., Radnaev, A. G., Dudin, Y. O., Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305, and Lebedev Physical Institute, Frequency Standards Laboratory, Moscow. Testing Local Position Invariance with Four Cesium-Fountain Primary Frequency Standards and Four NIST Hydrogen Masers. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.070802.
Ashby, N., Heavner, T. P., Jefferts, S. R., Parker, T. E., Radnaev, A. G., Dudin, Y. O., Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305, & Lebedev Physical Institute, Frequency Standards Laboratory, Moscow. Testing Local Position Invariance with Four Cesium-Fountain Primary Frequency Standards and Four NIST Hydrogen Masers. United States. doi:10.1103/PHYSREVLETT.98.070802.
Ashby, N., Heavner, T. P., Jefferts, S. R., Parker, T. E., Radnaev, A. G., Dudin, Y. O., Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305, and Lebedev Physical Institute, Frequency Standards Laboratory, Moscow. Fri . "Testing Local Position Invariance with Four Cesium-Fountain Primary Frequency Standards and Four NIST Hydrogen Masers". United States. doi:10.1103/PHYSREVLETT.98.070802.
@article{osti_20955460,
title = {Testing Local Position Invariance with Four Cesium-Fountain Primary Frequency Standards and Four NIST Hydrogen Masers},
author = {Ashby, N. and Heavner, T. P. and Jefferts, S. R. and Parker, T. E. and Radnaev, A. G. and Dudin, Y. O. and Time and Frequency Division, National Institute of Standards and Technology, Boulder, Colorado 80305 and Lebedev Physical Institute, Frequency Standards Laboratory, Moscow},
abstractNote = {We report the most sensitive tests to date of the assumption of local position invariance (LPI) underlying general relativity, based on a 7 yr comparison of cesium and hydrogen atomic clocks (frequency standards). The latest results place an upper limit that is over 20 times smaller than the previous most sensitive tests; this is consistent with the null shift predicted by LPI. The result is based on precise comparisons of frequencies of four hydrogen masers maintained by NIST, with four independent Cs fountain clocks--one at NIST and three in Europe--as the Sun's gravitational potential at Earth's surface varies due to Earth's orbital eccentricity.},
doi = {10.1103/PHYSREVLETT.98.070802},
journal = {Physical Review Letters},
number = 7,
volume = 98,
place = {United States},
year = {Fri Feb 16 00:00:00 EST 2007},
month = {Fri Feb 16 00:00:00 EST 2007}
}
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