The applications of laser in industry and science are so many and so varied as lo susjcst magic. Scientists in many countries working at a very inieresting problem: combining the two big technological discoveries of the second half of the 20th centry -laser and thermonuclear reaction — to produce a practically limitless source of energy. Physicists of this country have developed large laser installations to conduct physical experiments in heating thermonuclear fuel wiih laser beams. There also exists an idea to use laser for solving the problem of controlled thermonuclear reaction. The laser beam must heat ihe fuel to the required temperature so quickly that the plasma does not have time to disintegrate. According to current estimates, the duration of the pulse has to be approximately a billionth of a second. The light capacity of this pulse would be dozens of times greater than the capacity of all the world's power plants. To meet such demands in practice, scientists and enginners must work hard as it is clear that a lot of difficulties are to be encountered on route.
The laser's most important potential may be its use in communications. The intensity of a laser can be rapidly changed to encode very complex signals. In principle, one laser beam, vibrating a billion times faster than ordinary radio waves, could carry the radio,TV and telephone messages of the world simultaneously. In just a fraction of a second, for example, one laser beam could transmit the entire texl of the Encyclopaedia Britannica.
Besides, there are projects to use lasers for long distance communication and for transmission of energy to space stations, to the surface of the Moon or to planets in the Solar system. Projects have also been suggested to place lasers aboard Earth satellites nearer to the Sun in order to transform the solar radiation into laser beams, with this transformed energy subsequently trasmitted lo the Earth or to other space bodies. These projects have nol yet been put into effect, because of the great technological difficulties to be overcome and, therefore, the great cost involved. But there is no doubt that in time these projects will be realized and the laser beam will begin operating in outer space as well.