Experimental limits on neutron disappearance into another braneworld

Abstract

Recent theoretical works have shown that matter swapping between two parallel braneworlds could occur under the influence of magnetic vector potentials. In our visible world, galactic magnetism possibly produces a huge magnetic potential. As a consequence, this paper discusses the possibility to observe neutron disappearance into another braneworld in certain circumstances. The setup under consideration involves stored ultracold neutrons − in a vessel − which should exhibit a non-zero probability p to disappear into an invisible brane at each wall collision. An upper limit of p is assessed based on available experimental results. This value is then used to constrain the parameters of the theoretical model. Possible improvements of the experiments are discussed, including enhanced stimulated swapping by artificial means.

Corrections to Newton’s law of gravitation in the context of codimension-1 warped thick braneworlds

“…Besides the search for extra dimension evidences in high energy particle colliders, it could be also observed in low-energy experiments using neutrons if a second brane exists close enough to us [11]. Neutrons are more suitable than electrons, protons or atoms for such purpose [12].…”

“…Ultracold neutrons stored in a vessel would therefore have a non-zero probability to escape from our brane toward the hidden brane at each wall collision. Such a process would be perceived as a neutron disappearance from the point of view of an observer in the visible brane [11]. At last, it is worthwhile to mention the quite recently work by Yu and collaborators [19], which proposed that gravitational wave observations of compact binaries and their possible electromagnetic counterparts may be used to probe the nature of the extra dimension.…”

Sub-GeV-scale signatures of hidden braneworlds up to the Planck scale in a SO(3,1)-broken bulk

“…However, in the last decade, one of us (M.S.) and collaborators showed theoretically that matter exchange could occur at low energy between closest braneworlds in the bulk [38][39][40][41][42][43]. For instance, neutron swapping is allowed between our visible Universe and a parallel one hidden in the bulk [38][39][40][41][42].…”

“…and collaborators showed theoretically that matter exchange could occur at low energy between closest braneworlds in the bulk [38][39][40][41][42][43]. For instance, neutron swapping is allowed between our visible Universe and a parallel one hidden in the bulk [38][39][40][41][42]. Such an effect is probed in some experiments involving search for passing-through-walls neutrons in the vicinity of a nuclear reactor [40,41,55] or search for unusual leaks when dealing with ultra-cold neutron storage [42].…”

“…For instance, neutron swapping is allowed between our visible Universe and a parallel one hidden in the bulk [38][39][40][41][42]. Such an effect is probed in some experiments involving search for passing-through-walls neutrons in the vicinity of a nuclear reactor [40,41,55] or search for unusual leaks when dealing with ultra-cold neutron storage [42]. The ability for a neutron to leap from our visible world into a hidden braneworld (or reciprocally) is given by a swapping probability p [39], which can be experimentally probed [40][41][42]55].…”