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Multiple choice
Two qubits are in the pure state
a
∣
00
⟩
+
b
∣
11
⟩
a|00\rangle + b|11\rangle
a
∣00
⟩
+
b
∣11
⟩
with
a
=
3
/
2
a = \sqrt{3}/2
a
=
3
/2
and
b
=
1
/
2
b = 1/2
b
=
1/2
. The reduced state of qubit A is diagonal with eigenvalues
∣
a
∣
2
|a|^2
∣
a
∣
2
and
∣
b
∣
2
|b|^2
∣
b
∣
2
. What is the entanglement entropy
S
=
−
∑
λ
log
2
(
λ
)
S = -\sum \lambda \log_2(\lambda)
S
=
−
∑
λ
lo
g
2
(
λ
)
, in bits?
0.811
0.5
0.918
1
Check answer