Matrix t2*K(2) in Subspace 78 with Dimension 8

(K(2) is the second-order Grosse operator)

(3*t*U)/2 t^2*(-2 - U^2/t^2) 0 -(Sqrt[3]*t*U) Sqrt[6]*t^2 0 Sqrt[6]*t^2 (Sqrt[3]*t*U)/2
t^2*(-2 - U^2/t^2) (-3*t*U)/2 0 0 -(Sqrt[6]*t*U) -(Sqrt[3]*t*U) Sqrt[3/2]*t*U -2*Sqrt[3]*t^2
0 0 -2*t*U -(t*U) 0 4*t^2 0 0
-(Sqrt[3]*t*U) 0 -(t*U) (-9*t*U)/2 -2*Sqrt[2]*t^2 0 (4*t^2 - U^2)/Sqrt[2] 0
Sqrt[6]*t^2 -(Sqrt[6]*t*U) 0 -2*Sqrt[2]*t^2 -3*t*U 2*Sqrt[2]*t*U t*U -(Sqrt[2]*t^2)
0 -(Sqrt[3]*t*U) 4*t^2 0 2*Sqrt[2]*t*U -5*t*U 0 0
Sqrt[6]*t^2 Sqrt[3/2]*t*U 0 (4*t^2 - U^2)/Sqrt[2] t*U 0 -2*t*U -(Sqrt[2]*t^2)
(Sqrt[3]*t*U)/2 -2*Sqrt[3]*t^2 0 0 -(Sqrt[2]*t^2) 0 -(Sqrt[2]*t^2) (-15*t*U)/2