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Wilson lines, Grassmannians and gauge invariant off-shell amplitudes in \( \mathcal{N}=4 \) SYM. (English) Zbl 1378.81135

Summary: In this paper we consider tree-level gauge invariant off-shell amplitudes (Wilson line form factors) in \( \mathcal{N}=4 \) SYM. For the off-shell amplitudes with one leg off-shell we present a conjecture for their Grassmannian integral representation in spinor helicity, twistor and momentum twistor parameterizations. The presented conjecture is successfully checked against BCFW results for \(MHV_n\), \(NMHV_4\) and \(NMHV_5\) off-shell amplitudes. We have also verified that our Grassmannian integral representation correctly reproduces soft (on-shell) limit for the off-shell gluon momentum. It is shown that the (deformed) off-shell amplitude expressions could be also obtained using quantum inverse scattering method for auxiliary \( \mathfrak{g}\mathfrak{l}\left(4 | 4\right) \) super spin chain.

MSC:

81T60 Supersymmetric field theories in quantum mechanics
81T13 Yang-Mills and other gauge theories in quantum field theory
81U15 Exactly and quasi-solvable systems arising in quantum theory
83C60 Spinor and twistor methods in general relativity and gravitational theory; Newman-Penrose formalism

Software:

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References:

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