FCGramMatrix
FCGramMatrix[{p1, p2, ...}]
creates a Gram matrix from the given list of momenta.
See also
Overview, FCGramDeterminant.
Examples
(2p122(p1⋅p2)2(p1⋅p2)2p22)
FCGramMatrix[{p1, p2, p3}]
2p122(p1⋅p2)2(p1⋅p3)2(p1⋅p2)2p222(p2⋅p3)2(p1⋅p3)2(p2⋅p3)2p32
FCGramMatrix[{p1, p2, p3}, Head -> {CartesianPair, CartesianMomentum},Dimension -> D - 1]
Det[%]
2p122(p1⋅p2)2(p1⋅p3)2(p1⋅p2)2p222(p2⋅p3)2(p1⋅p3)2(p2⋅p3)2p32
−8p32(p1⋅p2)2−8p12(p2⋅p3)2−8p22(p1⋅p3)2+8p12p22p32+16(p1⋅p2)(p1⋅p3)(p2⋅p3)
FCGramDeterminant[{p1, p2, p3}, Head -> {CartesianPair, CartesianMomentum}, Dimension -> D - 1]
−8p32(p1⋅p2)2−8p12(p2⋅p3)2−8p22(p1⋅p3)2+8p12p22p32+16(p1⋅p2)(p1⋅p3)(p2⋅p3)