Fully explorable horned particles hiding charge

Abstract

The charge-hiding effect by a horned particle, which was studied for the case where the gravity/gauge-field system is self-consistently interacting with a charged light-like brane (LLB) as a matter source, is now studied for the case of a time-like brane. From the demand that no surfaces of infinite coordinate time redshift (horizons) appear in the problem, we are now led to a completely explorable horned particle space for a traveller that goes through the horned particle (as was the case for the LLB). Now, in addition to this, the horned region is fully visible to a static external observer. This requires negative surface energy density for the shell sitting at the throat. We study a gauge-field subsystem that is of a special nonlinear form containing a square root of the Maxwell term and that previously has been shown to produce a QCD-like confining gauge-field dynamics in flat spacetime. The condition of finite energy of the system or asymptotic flatness on one side of the horned particle implies that the charged object sitting at the throat expels all the flux it produces into the other side of the horned particle, which turns out to be of a ‘tube-like’ nature. An outside observer in the asymptotically flat universe detects, therefore, an apparently neutral object. The hiding of the electric flux behind the tube-like region of a horned particle is the only possible way that a truly charged particle can still be of finite energy, in a theory that in flat space it describes confinement. This points to the physical relevance of such solutions, even though there is the need of negative energy density at the throat of the horned particle, which can be of quantum-mechanical origin.