# Non-Monogamy of Spatio-Temporal Correlations and the Black Hole Information Loss Paradox

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## Abstract

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## 1. Introduction

## 2. Results

## 3. Discussion

## 4. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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**Figure 1.**Experimental setup. A maximally entangled singlet state is generated by pumping a type-II ${\mathrm{Beta}-\mathrm{BaB}}_{2}$${\mathrm{O}}_{4}$ (BBO) crystal. Two polarization measurements, M1 and M2 (at times ${t}_{1}$ and ${t}_{2}$, respectively) are performed in sequence on photon A, while a single measurement (M3) is carried on photon B. Correlations among them certify entanglement monogamy violation for the whole pseudo-density operator (PDO) ${R}_{123}$ in Equation (2), describing the scenario of the spatio-temporal multi-partite entanglement (outside and inside the black hole) considered.

**Figure 2.**Tomographic reconstruction of the real (panel

**a**) and imaginary (panel

**b**) part of the reduced pseudo-density operator ${R}_{12}=\frac{1}{4}(I+{\mathsf{\Sigma}}_{12})$, describing the temporal correlations between qubits 1 and 2, compared with the corresponding theoretical expectations (panels

**c**and

**d**, respectively).

**Figure 3.**Tomographic reconstruction of the real (panel

**a**) and imaginary (panel

**b**) part of the reduced pseudo-density operator ${R}_{13}=\frac{1}{4}(I-{\mathsf{\Sigma}}_{13})$, related to the spatially maximally entangled state within the black hole, compared with the corresponding theoretically-expected counterparts (panels

**c**and

**d**, respectively).

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## Share and Cite

**MDPI and ACS Style**

Marletto, C.; Vedral, V.; Virzì, S.; Rebufello, E.; Avella, A.; Piacentini, F.; Gramegna, M.; Degiovanni, I.P.; Genovese, M.
Non-Monogamy of Spatio-Temporal Correlations and the Black Hole Information Loss Paradox. *Entropy* **2020**, *22*, 228.
https://doi.org/10.3390/e22020228

**AMA Style**

Marletto C, Vedral V, Virzì S, Rebufello E, Avella A, Piacentini F, Gramegna M, Degiovanni IP, Genovese M.
Non-Monogamy of Spatio-Temporal Correlations and the Black Hole Information Loss Paradox. *Entropy*. 2020; 22(2):228.
https://doi.org/10.3390/e22020228

**Chicago/Turabian Style**

Marletto, Chiara, Vlatko Vedral, Salvatore Virzì, Enrico Rebufello, Alessio Avella, Fabrizio Piacentini, Marco Gramegna, Ivo Pietro Degiovanni, and Marco Genovese.
2020. "Non-Monogamy of Spatio-Temporal Correlations and the Black Hole Information Loss Paradox" *Entropy* 22, no. 2: 228.
https://doi.org/10.3390/e22020228