标题： 超双曲BMS群HB.II的表示 从无限小群诱导的表示的确定 显示英文标题

标题： Representations of the ultrahyperbolic BMS group HB.II. Determination of the representations induced from infinite little groups

摘要： 普通Bondi-Metzner-Sachs（BMS）群B是所有渐近平坦洛伦兹时空的共同渐近对称群。 因此，B是广义相对论的通用对称群的最佳候选。 然而，在研究量子引力时，经常考虑不同于通常洛伦兹签名的空间时光以及复数空间时光。 已经定义了适用于这些其他签名的B的推广形式。 特别是，适用于超双曲签名(+,+,-,-)的BMS群HB已在以前的论文中定义，其中表明HB的所有强连续酉不可约表示(IRs)都可以通过Wigner-Mackey的诱导方法获得，并且HB的所有小群都是紧致的。 在这里，我们详细描述HB的所有无限小群，并找到由它们诱导的HB的IRs。 显示英文摘要

摘要： The ordinary Bondi-Metzner-Sachs (BMS) group B is the common asymptotic symmetry group of all asymptotically flat Lorentzian space-times. As such, B is the best candidate for the universal symmetry group of General Relativity. However, in studying quantum gravity, space-times with signatures other than the usual Lorentzian one, and complex space-times, are frequently considered. Generalisations of B appropriate to these other signatures have been defined earlier. In particular, the generalisation HB, a BMS group appropriate to the ultrahyperbolic signature (+,+,-,-), has been defined in a previous paper where it was shown that all the strongly continuous unitary irreducible representations (IRs) of HB can be obtained with the Wigner-Mackey's inducing method and that all the little groups of HB are compact. Here we describe in detail all the infinite little groups of HB and we find the IRs of HB induced by them.