  A method of detecting of short scalar gravitational waves with a wavelength
of ~ 0.5 micrometers is proposed, in contrast to LIGO Project, aimed at
detecting of long quadrupole gravitational waves with a wavelength in interval
from 43 till 10000 km. The conduction electrons in a metal are proposed to use
as gravitational receiving antennas (pendulums) instead of massive mirrors in
LIGO. It is shown that using a Large Scale metal diffraction grating with area
of 25 m^2 you can convert the mechanical vibrations of the conduction electrons
of metal into a plane electromagnetic wave propagating along the normal to the
grating. It is shown that when the amplitude of the scalar gravitational wave
in a source (in quasar at the centre of our galaxy) is greater than Ag0 = 10^20
cm/(s^2), you can register it with the help of a large optical telescope
equipped with the proposed diffraction grating. It is shown that the special
theory of relativity allows the amplitude of the scalar gravitational waves in
this source by 5 orders of magnitude greater than the above-mentioned minimum
value.
