Massive stealth scalar fields from deformation method

Abstract

Extending the results of our previous work we construct an uniparametric class of action principles for complex scalar fields with the property that their energy momentum tensor and the electric current vanish for certain massive configurations. These stealth fields do not curve the spacetime and they do not source electromagnetic fields in spite their non-trivial degrees of freedom and U p1q gauge invariance. We shall also show that the presence of these stealth fields can affect the strength of the gravity-matter and radiation-matter coupling of other massive configurations. Indeed, the energy momentum tensor of other massive (non-stealth) configurations and the electric current can be rescaled (with a stealth-mass depending factor) with respect to the predictions of the standard complex scalar field model. Hence we argue that stealth fields could be detected indirectly by means of their effects on standard configurations of matter.

Electromagnetically and gravitationally stealth fields

“…In this section we shall follow closely reference [28]. This is, in D-dimensional spacetime dimensions, with dynamical metric g µν with signature (−, +, +, .…”

“…Extending the results of reference [28], we consider a generic action principle for a complex scalar field coupled to gravity and electromagnetism. According to a determined procedure we obtain a new deformed action principle, which is a uni-parametric extension of the original model containing stealth fields.…”

Stealth's cosmologies

“…As was pointed out in the previous section, the value for ζ c = 12/73 is not described by (16). In order to get the solution for this value we substitute directly ζ = ζ c on (15), so we have…”

“…This particular fact does not induce a back-reaction on the background spacetime where the stealths propagate. The stealth fields based on the Einstein field equations as well as in some modified gravity field equations have been fairly studied in the last few years where their existence has been proved in several gravitational contexts [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19]. In any case, despite the wealth of references quoted the subject, from the field equations little can be concluded regarding the interaction between a stealth field and ordinary matter.…”