COMPETITION BETWEEN GRAVITATIONAL AND SCALAR FIELD RADIATION

摘要

Recent astrophysical observations have provided strong evidence that the present expansion of the universe is accelerating, powered by the energy density associated with a cosmological term. Assuming the latter to be not simply a constant term but a "quintessence" field, we study the radiation of quanta of such a quintessence field ("quintans") by binary systems of different types and compare intensities to those of standard tensor gravitational wave emission. We consider both the case in which the quintessence field varies only over cosmological distances and the case in which it is modified spatially by (strong) gravitational fields, a condition that results in bounds on the gradient of the scalar field. We show that, in both the first case and, because of a bound we derive from the Hulse-Taylor pulsar, in the second, there is not sufficient quinton radiation to affect expected LISA and LIGO gravity wave signals from binary systems. We show that in the second case, the Large Hadron Collider is capable of setting a bound similar to that from the binary pulsar.