Development of Optical Transducer for Gravitational wave detector based on Resonating massive vibrator

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When Einstein constructed the theory of general relativity, he predicted the existence of gravitational wave (GW). Indirect observation of GW was already done in the latter of the last century, while its direct observation has been still unsuccessful. In other words, the direct observation of the GW is one of fundamental subject of physics in this century.We started developing a transducer for detection of the GW signals to be attached on a vibrational massive resonator type antenna working at a low temperature. As possible transducers to detect vibrations due to the GW, we examined optical interferrometer, SQUID, Piezo element, and capacitive pickup. For enabling computer control and data taking, we have introduced a Lab-view system.Meanwhile, we started investigating fundamental physics associated with the GW. In collaboration with the group of the GW antenna from Padova, Italy, we discussed possible existence of the gravitomagnetic moments of elementary particles. As a result, we predict that each elementary particle may have a gravitational moment such as a gravitational electric dipole moment and/or gravitational magnetic dipole moment by the multipple expansion of the gravitational field in a similar way to the procedure of the electromagnetic theory.The former moment will be present when the equivalence principle is broken, while the latter moment was the term which was first predicted by Linse-Thirring just after the advent of the general relativity in 1916. The origin of this term is associated with thei effect induced by the rotating gravitational mass and sometimes called the Frame dragging. This term is expected for example, in the rotating earth or neutron star binary.Efforts to find this term has initiated in the world scale by using sattelites or astronomical observation. However, no one has ever predicted existence of such moments, in particular, the gravitomagnetic dipole moment inherent in the elementary particles.