Dual superconformal invariance, momentum twistors and Grassmannians
Dual superconformal invariance, momentum twistors and Grassmannians
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DOI：
10.1088/1126-6708/2009/11/045
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发表时间：
2009-09
影响因子：
5.4
通讯作者：
L. Mason;David Skinner
中科院分区：
文献类型：
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作者：
L. Mason;David Skinner
在=4的超杨-米尔斯理论中，对偶超共形不变性是平面散射振幅的一种隐含对称性。这种对称性可以通过用“动量扭矩”来表示振幅来表现，而不是用通常的扭矩来表现普通的超共形性质。动量旋量和壳层动量之间的关系是代数的，因此平移过程不依赖于任何时空签名的选择。我们证明了树的振幅和盒系数是由全纯δ函数在格拉斯曼周期上的动量扭曲中积分而简洁地产生的。这与Arkani-Hamed等人最近获得的结果相似，但不同。在普通的龙卷风空间。我们还联系到了Hodges在动量扭曲空间中NMHV振幅的多面体表示。
Dual superconformal invariance has recently emerged as a hidden symmetry of planar scattering amplitudes in = 4 super Yang-Mills theory. This symmetry can be made manifest by expressing amplitudes in terms of `momentum twistors', as opposed to the usual twistors that make the ordinary superconformal properties manifest. The relation between momentum twistors and on-shell momenta is algebraic, so the translation procedure does not rely on any choice of space-time signature. We show that tree amplitudes and box coefficients are succinctly generated by integration of holomorphic δ-functions in momentum twistors over cycles in a Grassmannian. This is analogous to, although distinct from, recent results obtained by Arkani-Hamed et al. in ordinary twistor space. We also make contact with Hodges' polyhedral representation of NMHV amplitudes in momentum twistor space.