(−1)
σ
j
a
+
j
a
j
a
+
k
a
k
a
+
j
a
j
0
F (−1)
σ
0
σ
0
=
j
0
−1
P
s+j
n
s
= j
0
− j |¯ni ∈ F
j j
0
1
√
2
|000 . . . 0i +
1
√
2
|111 . . . 1i
|0i −→ |1i, |1i −→ |0i |0i −→ |0i, |1i −→ |0i
ξ
0
=
1
√
2
|100 . . . 0i+
1
√
2
|011 . . . 1i ξ
0
=
1
√
2
|000 . . . 0i+
1
√
2
|011 . . . 1i
λ|0, 0, 0i+ µ|1, 1, 1i
|0, 0, 0i |1, 1, 1i