Wilson Loop Diagrams and Positroids

@article{Agarwala2015WilsonLD,
  title={Wilson Loop Diagrams and Positroids},
  author={Susama Agarwala and Eloi Marin-Amat},
  journal={Communications in Mathematical Physics},
  year={2015},
  volume={350},
  pages={569-601}
}
In this paper, we study a new application of the positive Grassmannian to Wilson loop diagrams (or MHV diagrams) for scattering amplitudes in N= 4 Super Yang–Mill theory (N = 4 SYM). There has been much interest in studying this theory via the positive Grassmannians using BCFW recursion. This is the first attempt to study MHV diagrams for planar Wilson loop calculations (or planar amplitudes) in terms of positive Grassmannians. We codify Wilson loop diagrams completely in terms of matroids… 
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14 Citations
Background Citations
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Methods Citations
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14 Citations

Combinatorics of the geometry of Wilson loop diagrams II: Grassmann necklaces, dimensions, and denominators

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3 0 A pr 2 01 9 Basis shape loci and the positive Grassmannian

A basis shape locus takes as input data a zero/nonzero pattern in an n× k matrix, which is equivalent to a presentation of a transversal matroid. The locus is defined as the set of points in Gr(k, n)…

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