%0 Journal Article %T Optical-Gravitation Nonlinearity: A Change of Gravitational Coefficient G induced by Gravitation Field %A R. Vlokh %A M. Kostyrko %J Ukrainian Journal of Physical Optics %D 2006 %I Institute of Physical Optics %X Nonlinear effect of the gravitation field of spherically symmetric mass on the gravitational coefficient G has been analysed. In frame of the approaches of parametric optics and gravitation nonlinearity we have shown that the gravitation field of spherically symmetric mass can lead to changes in the gravitational coefficient G. %K gravitation field %K gravitational coefficient %K optical-mechanical analogy in general relativity %U http://www.ifo.lviv.ua/journal/UJPO_PDF/2006_4/0504_2006.pdf