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(ed.). Gravitational waves (IOP, 2001)(422s).

(ed.). Gravitational waves (IOP, 2001)(422s).

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Chapter 15Gyroscopes and gravitational <strong>waves</strong>Donato Bini 1 and Fernando de Felice 21 Istituto per Applicazioni della Matematica, CNR, I-80131Napoli, Italy and International Center for RelativisticAstrophysics, University of Rome, I-00185 Roma, Italy2 Dipartimento di Fisica ‘G. Galilei’, Università degli Studi diPadova, Via Marzolo, 8, I-35131, Padova, Italy and INFN,Sezione di Padova, ItalyThe behaviour of a gyroscope in geodesic motion is studi<strong>ed</strong> in the field ofa plane gravitational wave. We find that, with respect to a special set offrames, the compass of inertia undergoes a precession which, to first order in th<strong>ed</strong>imensionless amplitude h of the wave, is dominat<strong>ed</strong> by the cross-polarizationalone. This suggests that a gyro might act as a filter of the polarization state ofthe wave.15.1 IntroductionThe (direct) detection of gravitational <strong>waves</strong> is still an open question, althoughindirect evidence for their existence has been obtain<strong>ed</strong> from the observationof the binary pulsar system PSR 1913+16 [1]. Besides the well-known barantennae, there is a growing interest in laser interferometry detectors, like LIGOand VIRGO, which are sensitive to the low frequency (∼10 Hz) gravitational<strong>waves</strong> which are emitt<strong>ed</strong> by sources like coalescing binaries.The purpose of this paper is to study the behaviour of a test gyroscopewhich is act<strong>ed</strong> upon by a plane gravitational wave with the purpose to seewhether this interaction leads to observable effects. It is well known that inthe absence of significant coupling between the background curvature and themultipole moments of the energy–momentum tensor of an extend<strong>ed</strong> body, thespin vector is Fermi–Walker transport<strong>ed</strong> along the body’s own trajectory (see [2]268

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