Nonconservation of global quantum numbers in RSbar-type models

Abstract

In Randall-Sundrum type scenarios the effective size of the extra dimension remains unconstrained. A TeV-scale brane tension without orbifold boundary conditions would allow phenomenologically observable processes at high energy colliders. Among others, the brane could fragment into bubbles that fly away for good or return within a time <O(1 mm)/c. Particles trapped on the bubbles may fake nonconservation of global or electric charges. In this letter we explore the generic (model independent) features of these bubbles. We describe the brane dynamics by a scalar field coupled derivatively to the energy momentum tensor by dimension-8 operators. Mass is generated to this field by any brane stabilization mechanism. The bubbles may be stabilized by the Casimir effect. When the threshold energy of sqrt{s}~brane tension > TeV is reached, bubbles with 1/TeV size are copiously produced. At lower sqrt{s}, smaller bubbles can be produced (if they exist) with strongly suppressed probability.