Two-loop six gluon all plus helicity amplitude

D. C. Dunbar and W. B. Perkins, arXiv:1603.07514 [hep-th]

Original

Cited in the paper.

D. C. Dunbar, G. R. Jehu and W. B. Perkins, arXiv:1604.06631 [hep-th]

Original

Cited in the paper.

As usual, a null momentum is represented as a pair of two component spinors p μ = σ α ​ α ˙ μ ​ λ α ​ λ ¯ α ˙ p^{\mu}=\sigma^{\mu}_{\alpha\dot{\alpha}}\lambda^{\alpha}\bar{\lambda}^{\dot{\alpha}} . For real momenta λ = ± λ ¯ ∗ \lambda=\pm\bar{\lambda}^{*} but for complex momenta λ \lambda and λ ¯ \bar{\lambda} are independent. We use the usual spinor products ⟨ j ​ l ⟩ ≡ ⟨ j − | l + ⟩ = u ¯ − ​ ( k j ) ​ u + ​ ( k l ) \left\langle j\,l\right\rangle\equiv\langle j^{-}|l^{+}\rangle=\bar{u}_{-}(k_{j})u_{+}(k_{l}) and [ j ​ l ] ≡ ⟨ j + | l − ⟩ = u ¯ + ​ ( k j ) ​ u − ​ ( k l ) \left[j\,l\right]\equiv\langle j^{+}|l^{-}\rangle=\bar{u}_{+}(k_{j})u_{-}(k_{l}) . In terms of spinors ⟨ a ​ b ⟩ = ϵ α ​ β ​ λ a α ​ λ b β \left\langle a\,b\right\rangle=\epsilon_{\alpha\beta}\lambda_{a}^{\alpha}\lambda_{b}^{\beta} and [ a ​ b ] = − ϵ α ˙ ​ β ˙ ​ λ ¯ a α ˙ ​ λ ¯ b β ˙ \left[a\,b\right]=-\epsilon_{\dot{\alpha}\dot{\beta}}\bar{\lambda}_{a}^{\dot{\alpha}}\bar{\lambda}_{b}^{\dot{\beta}} . We also use [ i | K a ​ b ​ c | j ⟩ [i|{K_{abc}}|j\rangle to denote ⟨ i + | K̸ a ​ b ​ c | j + ⟩ \langle i^{+}|\not{K}_{abc}|j^{+}\rangle with K a ​ b ​ c μ = k a μ + k b μ + k c μ K_{abc}^{\mu}=k_{a}^{\mu}+k_{b}^{\mu}+k_{c}^{\mu} etc. Also s a ​ b = ( k a + k b ) 2 s_{ab}=(k_{a}+k_{b})^{2} , t a ​ b ​ c = ( k a + k b + k c ) 2 t_{abc}=(k_{a}+k_{b}+k_{c})^{2} , etc

Cited in the paper.

D. C. Dunbar and W. B. Perkins, arXiv:1601.03918 [hep-th]

Original

Cited in the paper.

W. B. Perkins, in preparation

Cited in the paper.

T. Gehrmann, J. M. Henn and N. A. Lo Presti, Phys. Rev. Lett. 116

Original

2016

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