A nonlinear chaotic gravitational-wave detector

In the present work we signalize the possibility of introducing into a syst em a component incorporating the generation of chaos as an element of high sensitivity in order to detect small changes in distances generated by grav itational waves. We propose the construction of a double-bar antenna with a coupling Josephson junction in its center of mass. Thus a classical detect or is converted into a parametric amplifier in which the parameters for a h igh parametric gain are the same as those required for an onset of chaos. T his is the first model of a macroscopic quantum nonlinear detector of gravi tational waves which uses chaos as a very sensitive sensor. Very small chan ge generated by the variation of the distance between the plates of a junct ion capacitance will produce very different intermittency routes to chaos. If all parameters of a nonlinear gravitational-wave antenna are maintained constant, the variations of the type of intermittency regime should indicat e the appearance of a gravitational wave. The sensitivity of the proposed t echnique is illustrated by computer experiments and appears to be at least of the same order as in the case of a classical linear antenna. We present also a generalization of the idea on an implementation of a chaotisizing el ement in a classical equation of a cosmological model. A stable Fermi-Walke r model is thus converted into a chaotic one in which inflation (high ampli fied turbulent expansion) may be generated as a result of a chaotisizing eq uation of stare or a gravitational constant. (C) 1999 Elsevier Science Ltd. All rights reserved.