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Feasibility of measuring the Shapiro time delay over meter-scale distances

Ballmer, S. and Márka, S. and Shawhan, P. (2010) Feasibility of measuring the Shapiro time delay over meter-scale distances. Classical and Quantum Gravity, 27 (18). Art. No. 185018 . ISSN 0264-9381.

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The time delay of light as it passes by a massive object, first calculated by Shapiro in 1964, is a hallmark of the curvature of spacetime. To date, all measurements of the Shapiro time delay have been made over solar-system distance scales. We show that the new generation of kilometer-scale laser interferometers being constructed as gravitational wave detectors, in particular Advanced LIGO, will in principle be sensitive enough to measure variations in the Shapiro time delay produced by a suitably designed rotating object placed near the laser beam. We show that such an apparatus is feasible (though not easy) to construct, present an example design, and calculate the signal that would be detectable by Advanced LIGO. This offers the first opportunity to measure spacetime curvature effects on a laboratory distance scale.

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Additional Information:© 2010 IOP Publishing Ltd. Received 6 May 2010, in final form 13 July 2010. Published 4 August 2010. LIGO was constructed by the California Institute of Technology and Massachusetts Institute of Technology with funding from the National Science Foundation and operates under cooperative agreements PHY-0107417 and PHY-0757058. The authors are also grateful for the support of the National Science Foundation under grants PHY-0457528, PHY-0653421, PHY-0757957 and PHY-0757982; Columbia University in the City of New York; the University of Maryland; and the California Institute of Technology. We are indebted to many of our colleagues for fruitful discussions, in particular Daniel Sigg, Rainer Weiss, Rubab Khan and Zsuzsa Márka, and to Yoichi Aso for providing figure 1. We also thank an anonymous referee for helpful suggestions. This document has LIGO document number LIGO-P080029-v2.
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Columbia University in the City of New YorkUNSPECIFIED
University of MarylandUNSPECIFIED
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Other Numbering System NameOther Numbering System ID
LIGO document number LIGO-P080029-v2
Issue or Number:18
Classification Code:PACS: 04.80.Nn; 95.55.Ym; 07.60.Ly. MSC: 83C35
Record Number:CaltechAUTHORS:20100907-140051932
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Official Citation:S Ballmer et al 2010 Class. Quantum Grav. 27 185018 doi: 10.1088/0264-9381/27/18/185018
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:19806
Deposited By: Tony Diaz
Deposited On:15 Sep 2010 21:34
Last Modified:03 Oct 2019 02:01

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