Alternative method of generation of Cerenkov radiation or shock wave

An alternative method of generation of Cerenkev radiation is proposed over here with the help of a rotating source and a reflector. The principle is that, if we focus a narrow beam of light on to source of light is rotated with certain angular velocity then the light spot on the surface will move with very high velocity which may exceed the velocity of light. As a consequence of this we shall observe an effect very similar to Cerknov radiation. Introduction It is an well established fact that a beam of light from a rotating source may sweep out a distant path faster than the speed of light [1, 2]. This can also be established in the following way. A narrow beam of light of monocharomatic wavelength λ from a source O rotates in the anticlockwise direction with an angular velocity ω and describes an angle ∆θ in time ∆t (Fig. 1). The radius r of the circle is large (or ∆θ be very small) to consider the path of the light spot BC stright line (Fig. 2 ) BC = l = r∆θ ∆θ = 1/r 1 ω = ∆θ/∆t The time taken by the light ray to travel from O to B (Fig. 3) i.e. the distance r is t. In time ∆t the light at O is rotated by an angle ∆θ and is in the direction OC. Since, light takes a time t to travel a distance r, so it will reach the point C after a time (t+∆t). so, ∆t is the time taken by the light spot to travel a distance BC = l. Therefore the velocity of the light spot is ν = 1/∆t or, ν = r∆θ/∆t(Since, l = r∆θ) or, ν = rω So, the velocity of the light spot = angular velocity of the source × radius of the circle on which the light spot moves We can make the velocity of the light spot ν greater than the velocity of light, either by increasing ω or by increasing r or both. As an example (Fig. 4) if a beam of laser is rotated at the surface of moon with one rotation per second (i.e. T = 1 sec, and ω = 2π/T = 2π/1), then the velocity of the light spot which touches the earth will move with a velocity ν = rω = r · 2π/T ν21.6× 10Con/sec. [taking, r = 3.37× 10 cm, the distance between moon and earth and T = 1 sec. ] Which is about seven times greater than the velocity of light. The possiblity that a light-spot can move faster than light is discussed in references 1 and 2. So, when a spot of light moves faster than the light itself then we can expect an effect very similar to Cerenkov radiation [3].