# Non-Local Parity Measurements and the Quantum Pigeonhole Effect

## Abstract

**:**

## 1. Introduction

## 2. Results

## 3. Discussion

## 4. Conclusions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**Circuit schematic for the quantum pigeonhole effect based on entanglement distillation. The double dotted line represents the entanglement between Alice’s and Bob’s ancilla qubits, which were prepared in the Bell state $|{\mathsf{\Phi}}^{+}\rangle $. The dotted line is a classical channel that transmits the results of the measurements of the ancilla qubits to a classical XOR gate. A parity with the result “same” corresponds to the classical output of XOR having the value 0, while for “different”, it takes a value of 1.

**Figure 2.**Circuit schematic for the quantum pigeonhole effect based on non-local CNOT gates. As in the previous figure, entanglement is shown with a dotted double line, while classical communication is shown with dashed lines. The result of the measurement is “same" when the oracle qubit is measured to be 0, and “different" when the oracle is measured to be 1.

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**MDPI and ACS Style**

Paraoanu, G.S.
Non-Local Parity Measurements and the Quantum Pigeonhole Effect. *Entropy* **2018**, *20*, 606.
https://doi.org/10.3390/e20080606

**AMA Style**

Paraoanu GS.
Non-Local Parity Measurements and the Quantum Pigeonhole Effect. *Entropy*. 2018; 20(8):606.
https://doi.org/10.3390/e20080606

**Chicago/Turabian Style**

Paraoanu, G. S.
2018. "Non-Local Parity Measurements and the Quantum Pigeonhole Effect" *Entropy* 20, no. 8: 606.
https://doi.org/10.3390/e20080606