Towards the Gravituhedron: New Expressions for NMHV Gravity Amplitudes

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In this paper, we present new expressions for n-point NMHV tree-level gravity amplitudes.

• We introduce a method of factorization diagrams which is a simple graphical representation of R-invariants in Yang-Mills theory.
• We define the gravity analogues which we call G-invariants, and expand the NMHV gravity amplitudes in terms of these objects.
• We provide explicit formulas of NMHV gravity amplitudes up to eight points in terms of G-invariants, and give the general definition for any number of points.