The asymptotic structure of gravity in D = 6 spacetime dimensions is described at spatial infinity in the asymptotically flat context through Hamiltonian (ADM) methods. Special focus is given on the Bondi–Metzner–Sachs (BMS) supertranslation subgroup. It is known from previous studies that the BMS group contains more supertranslations as one goes from D = 4 to D = 5. Indeed, while the supertranslations are described by one single function of the angles in D = 4, four such functions are neeeded in D = 5. We consider the case D = 6 with the aim of determining whether the number of supertranslations keeps increasing with the dimension or remains equal to the number found in D = 5. We show that even though there is apparent room for more supertranslations, their number remains equal to the D = 5 value (four): the potentially new supertranslations turn out to define proper gauge transformations corresponding to a redundancy in the description of the system. Critical in the analysis are the boundary conditions chosen to yield a well-defined canonical formalism. Given the computational (but not conceptual) complexity as one increases the dimension, we explicitly discuss the linearized theory and argue that asymptotically, this analysis provides the correct picture. We conclude by considering higher spacetime dimensions where we indicate that the number of physically relevant supertranslations remains equal to four independently of the dimension ⩾5 .Contribution to Stanley Deser memorial volume ‘Gravity, Strings and Beyond’

中文翻译：

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D = 6 个时空维度中的 BMS 群

引力的渐近结构D = 6 个时空维度通过哈密顿量 (ADM) 方法在渐近平坦环境中的空间无限处进行描述。特别关注 Bondi-Metzner-Sachs (BMS) 超级翻译小组。从之前的研究可知，BMS组包含的超翻译越多，越多。D = 4 至D = 5. 事实上，虽然超平移是由角度的单一函数描述的，D = 4, 需要四个这样的函数D = 5. 我们考虑这个案例D = 6，目的是确定超平移的数量是否随着维度的增加而不断增加，或者保持等于中发现的数量D = 5。我们表明，尽管明显有更多超级翻译的空间，但它们的数量仍然等于D = 5 值（四）：潜在的新超级翻译结果定义了与系统描述中的冗余相对应的适当规范变换。分析中的关键是选择边界条件来产生明确定义的规范形式主义。考虑到随着维度的增加，计算（但不是概念）的复杂性，我们明确讨论了线性化理论，并认为这种分析渐进地提供了正确的图景。我们通过考虑更高的时空维度来得出结论，其中我们表明物理相关的超平移的数量仍然等于四，而与维度无关 ⩾5 。为 Stanley Deser 纪念卷《重力、弦乐及超越》撰稿