Table 4 Theoretical probabilities of obtaining Bell state |Ψ−〉 for different combinations of Bob’s cheating states and Alice’s honest states in the second middle-state attack.
From: Loss-tolerant measurement-device-independent quantum private queries
- The operator ‘+’ in ‘±’ stands for the case
, while the operator ‘−’ in ‘±’ represents the case 
.
, while the operator ‘−’ in ‘±’ represents the case 
.