The excitation of a charged string passing through a shock wave in a charged Aichelburg-Sexl spacetime (時空特異点とその周辺)

概要

論文の詳細を見る
We investigate how much a first-quantized charged bosonic test string gets excited after crossing a shock wave generated by a charged particle with mass M^^〜 and charge Q^^〜. On the basis of Kaluza-Klein theory, we pay attention to a closed string model where charge is given by a momentum along a compactified extra-dimension. The shock wave is given by a charged Aichelburg-Sexl (GAS) spacetime where Q^^〜 = 0 corresponds to the ordinary Aichelburg-Sexl one. We first show that the CAS spacetime is a solution to the equations of motion for the metric, the gauge field, and the axion field in the low-energy limit. Secondly, we compute the mass expectation value of the charged test string after passing through the shock wave in the CAS spacetime. In the case of small Q^^〜, gravitational and Coulomb forces are canceled out each other and hence the excitation of the string remains very small. This is independent of the particle mass M^^〜 or the strength of the shock wave. In the case of large Q^^〜, however, every charged string gets highly excited by quantum fluctuation in the extra-dimension caused by both the gauge and the axion fields. This is quite different from classical "molecule", which consists of two electrically charged particles connected by a classical spring.
素粒子論グループ素粒子研究編集部の論文
2001-06-20