Страница 91 из 99
ν
⎞
⎠
⎤
⎥
⎦
=
exp
⎡
⎢
⎣
½Tr
⎛
⎜
⎝
2λ
ℎ
β
ν
-
1
2
(2λ)²
ℎ
β
τ
ℎ
τ
ν
+
1
3
(2λ)³
ℎ
β
τ
ℎ
τ
σ
ℎ
σ
ν
+…
⎞
⎟
⎠
⎤
⎥
⎦
=
exp
⎡
⎢
⎣
1
2
⎛
⎜
⎝
2λ
ℎ
β
β
-
1
2
2(λ)²
ℎ
β
τ
ℎ
τ
β
+
1
3
(2λ)³
ℎ
β
τ
ℎ
τ
σ
ℎ
σ
β
+…
⎞
⎟
⎠
⎤
⎥
⎦
=
1
+
λ
ℎ
β
β
-
λ²
⎛
⎝
ℎ
β
ρ
ℎ
ρ
β
+… .
⎞
⎠
(16.1.8)