What do gravitons say about (unimodular) gravity?
What do gravitons say about (unimodular) gravity?
复制标题
引力子对（单模）引力有何看法？
DOI：
10.1007/jhep12(2018)106
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发表时间：
2018
影响因子：
5.4
通讯作者：
M. Herrero
中科院分区：
文献类型：
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作者：
M. Herrero
我们重新审视从S矩阵性质来约束引力拉格朗日弱场极限的问题。从无质量引力子 S 矩阵的幺正性和洛伦兹不变性，我们推导出壳内规范不变性，它存在于线性微分同胚群的横向部分上。此外，通过研究源之间的相互作用，我们得出结论，仅存在两种可能的拉格朗日量可以导致明确定义的协变相互作用，对应于广义相对论和幺模引力的弱场极限。此外，这一结果证实了两种理论在平坦时空下的 S 矩阵的等价性。
We revisit the problem of constraining the weak field limit of the gravitational lagrangian from S-matrix properties. From unitarity and Lorentz invariance of the S-matrix of massless gravitons, we derive on-shell gauge invariance to consist on the transverse part of the linearised diffeomorphisms group. Moreover, by looking to the interaction between sources, we conclude that there exist only two possible lagrangians that lead to a welldefined covariant interaction, corresponding to the weak field limits of General Relativity and Unimodular Gravity. Additionally, this result confirms the equivalence of the S-matrix of both theories around flat space-time.