P.O. box 595, 420111, Kazan, Tatarstan, Russia.
The problem of gravitational waves (GW) detection, being the key problem of modern physics, has recently attracted particular attention of both theorists and experimentalists. On the one hand it is conditioned by the fact that gravitational-wave experiment is the determinative one, affecting theoretical foundations of modern physics. On the other hand, discovery and utilization of gravitational-wave channel for obtaining the information on the Universe construction, on the stellar structure and the gravity nature would, undoubtedly, enrich Science.
But there is another circumstance of not less value. Physics of our century had demonstrated a lot of examples, when relatively weak by intensity, but continuous factors can result in changing the structure of complex systems.
Gravitational-wave field can not compete with the other physical fields by the impact intensity, however, principle inability of its screening, generality, long-range action and particular tensor nature effect unpredictably on complex systems. Investigation of such fine phenomena, being extremely urgent, enriches conceptual, theoretical, technical and technological potential of modern physics. So, not only the fact of gravitational waves existence, but the process of their registration and measurement itself should become an extraordinary event for modern science.
At the beginning of twenty first century the most outstanding theorists and experimentalists of USA, Italy, Japan, France, Germany, Great Britain and Australia deal with investigations of gravitational phenomena. The direct experimental affirmation of gravitational radiation (GR) existence would become the most outstanding event in the world science.
In the Republic of Tatarstan (RT) research and development works are performed to realize the Project "Dulkyn", aimed at construction of the gravitational-wave detector "Dulkyn" which is the basic operational apparatus of Kazan gravitational-wave observatory "Dulkyn".
The history of the project "Dulkyn" and of scientific center for gravitational-wave research (SC GWR) "Dulkyn" is inseparable from Kazan State University (KSU) and, particularly, with the department of relativity theory and gravitation of KSU. In this connection it is necessary first of all to name N.I. Lobachevski - the originator of non-Euclidean geometry, who lived and worked in Kazan University and was its rector for 19 years. The creation of new geometry by Lobachevski was the most important stage in developing the science of space properties and promoted elaboration of further generalizations, the conception of Riemannian space, on which, in its turn, the general relativity theory is based, being one of them.
The second name to be told about while speaking of the history of SC GWR "Dulkyn" is professor of KSU A.Z. Petrov, who had founded the department of relativity theory and gravitation and was the first head of it. In 1954 A.Z. Petrov had proved a remarkable theorem, which made his name world-known. This theorem stated the existence of three types of Einstein spaces (subsequently these types were referred to as the Petrov' types ). Later it has been found out that the second and the third type space membership indicated the gravitational radiation presence in space. Thus one of the most complex and complicated and entangled problems of the general relativity theory was elucidated for the first time.
In 1961-1965 A.Z. Petrov had undertaken an effort to set up an experimental gravitational laboratory on the basis of the department of relativity theory and gravitation. However due to the fact that in 1969 A.Z. Petrov was elected as academician of the Academy of sciences of Ukrainian Soviet Socialistic Republic and moved to Kiev, this task was not finished.
But the idea of performing the experimental investigations in the field of gravitational physics in Kazan University had not been terminated, and after many years of searching for the ways of its realization in 1989 a decision of Comission of the USSR Council of Ministers (CM) N 427 of December, 27 on enabling the research work on gravitational-wave subject was taken. In 1990 the Gravitational-Wave Astronomy Sector in KSU was formed under the initiative of collaborators of the Department of relativity theory and gravitation, which was later transformed into the Research laboratory for Gravitational-wave astronomy of KSU as the investigations developed. The history of 'Dulkyn' project itself was initiated by the Resolution of CM of the Republic of Tatarstan (CM RT) N318 of July, 26 1991 'On experimental base formation for basic research in the field of gravitational-wave physics (on realization of the "Dulkyn" Project). The same year the basic strategy of building the gravitational-wave detector for detecting the gravitational waves from the binary astrophysical objects was proposed, and the project research team had been finally formed.
In 1993 the Resolution of CM RT ¹ 1225-p of December, 31 was taken on the approval of feasibility report on GW-observatory construction (state appraisal of engineering and economy assessment and budget). In the same year the feasibility report was developed on construction of the experimental gravitational-wave observatory "Dulkyn" in Laishevski district of RT. The Project total budget was evaluated as ~6 million $US.
In the same year early experiments on testing the soundness of basic scientific-and-engineering decisions on the GW-detector "Dulkyn" construction had started. To continue these and perform other experiments the United Experimental Laboratory of Gravitational-Optical Investigations (UELGOI) was formed in 1994 on the basis of Federal Scientific-Production Centre "State Institute of Applied Optics" (FSPC SIAO) (Russian abbreviation is FNPC GIPO), where the works on fabricating the pentagonal GW-detector prototype had started in 1995.
In 1994 according to the Resolution of CM RT ¹ 560 of November, 16 Scientific Center for Gravitational-Wave research "Dulkyn" was formed on terms of an institute of Academy of Sciences of RT with a right of artificial person, thereby the organizational framework of "Dulkyn" project had been finally arranged.
At elaborating the SC GWR "Dulkyn" forecast programme the objective (external) tendencies of integration of the geodesic, astrometric investigations and their convergence with the fundamental geophysics, geology, applied geological exploration and seismology were taken into account. The developed in SC GWR "Dulkyn" AS RT innovative facilities provide a unique possibility to unite the efforts of the above mentioned services, aimed at the development of fundamental and applied science, earlier, than in other research centres.
In December of 1995 the first prototype of pentagonal optic interferometer working in the passive regime was mounted, adjusted and successfully tested. In 1996-1997 the experiments on the prototype were performed, resulted in solving a series of important experimental problems. In 1997-2000 one inventor's certificate of authorship and six patents for invention were taken on the laser-interferometric detecting of gravitationally-induced shifts of generated frequency. Four patents applications are forwarded to the Russian Research Institute for State Patent Expertise (RRISPE).
In January of 1999 the vacuum chamber was fabricated and commissioned (exhaustion in vacuum chamber is up to 10-3 torr).
In July of 1999 the fabrication, alignment and adjustment of the prototype of the triangle variant of two-resonator laser system were finished, and optical radiation on standing waves was generated.
In August of 1999 the fabrication, alignment and adjustment of prototype of an active variant of the ring pentagonal two-resonator laser system were accomplished, and optical radiation on running waves was generated.
At present the proving of the systems of frequency and phase stabilization of optical radiations in two-contour resonators is performed, as well as adapting the photodetecting and optical blocks of active interferometer and preparation for mounting the pentagonal active interferometer, placed in the vacuum chamber, in the embedded experimental cabin. Besides, the theoretical investigations on possibility of developing the methods for decreasing the noise factor at the two-resonator laser system output are being performed.