
Exclusivity graph approach to Instrumental inequalities
Davide Poderini, Rafael Chaves, Iris Agresti, Gonzalo Carvacho, Fabio Sciarrino 
Quantum Markov monogamy inequalities
Matheus Capela, Lucas C. Céleri, Rafael Chaves, Kavan Modi 
Experimental deviceindependent certified randomness generation with an instrumental causal structure
Iris Agresti, Davide Poderini, Leonardo Guerini, Michele Mancusi, Gonzalo Carvacho, Leandro Aolita, Daniel Cavalcanti, Rafael Chaves, Fabio Sciarrino 
Quantum communication complexity beyond Bell nonlocality
Joseph Ho, George Moreno, Samuraí Brito, Francesco Graffitti, Christopher L. Morrison, Ranieri Nery, Alexander Pickston, Massimiliano Proietti, Rafael Rabelo, Alessandro Fedrizzi, Rafael Chaves 
Statistical Properties of the Quantum Internet
Samuraí Brito, Askery Canabarro, Rafael Chaves, Daniel Cavalcanti 
Weyl–Wigner representation of canonical equilibrium states
F NicacioThe WeylWigner representations for canonical thermal equilibrium quantum states are obtained for the whole class of quadratic Hamiltonians through a Wick rotation of the WeylWigner symbols of Heisenberg and metaplectic operators. The behavior of classical structures inherently associated to these unitaries is described under the Wick mapping, unveiling that a thermal equilibrium state is fully determined by a complex symplectic matrix, which sets all of its thermodynamical properties. The four categories of Hamiltonian dynamics (Parabolic, Elliptic, Hyperbolic, and Loxodromic) are analyzed. Semiclassical and high temperature approximations are derived and compared to the classical and/or quadratic behavior.

Causal Networks and Freedom of Choice in Bell’s Theorem
Rafael Chaves, George Moreno, Emanuele Polino, Davide Poderini, Iris Agresti, Alessia Suprano, Mariana R. Barros, Gonzalo Carvacho, Elie Wolfe, Askery Canabarro, Robert W. Spekkens, Fabio Sciarrino 
Deviceindependent secret sharing and a stronger form of Bell nonlocality
M. G. M. Moreno, Samuraí Brito, Ranieri V. Nery, Rafael Chaves 
General Method for Classicality Certification in the Prepare and Measure Scenario
Carlos de Gois, George Moreno, Ranieri Nery, Samuraí Brito, Rafael Chaves, Rafael Rabelo 
Bell nonlocality using tensor networks and sparse recovery
I. S. Eliëns, S. G. A. Brito, R. Chaves 
Williamson theorem in classical, quantum, and statistical physics
F. NicacioThe objective of this text is to present (and encourage the use of) the Williamson theorem and its consequences in several contexts in physics. The demonstration of the theorem is performed using only basic concepts of linear algebra and symplectic matrices. The immediate application is to place the study of small oscillations in the Hamiltonian scenario, where the theorem shows itself as a useful and practical tool for revealing the normalmode coordinates and frequencies of the system. A modest introduction of the symplectic formalism in quantum mechanics is presented, which consequently opens up the use of the theorem to study quantum normal modes and quantum small oscillations, allowing the theorem to be applied to the canonical distribution of thermodynamically stable systems described by quadratic Hamiltonians. As a last example, a more advanced topic concerning uncertainty relations is developed to show once more its utility in a distinct and modern perspective.

Semideviceindependent certification of entanglement in superdense coding
George Moreno, Ranieri Nery, Carlos de Gois, Rafael Rabelo, Rafael Chaves 
Monogamy of temporal correlations: Witnessing nonMarkovianity beyond data processing
Matheus Capela, Lucas C. Céleri, Kavan Modi, Rafael Chaves 
Mean value of the quantum potential and uncertainty relations
F. Nicacio, F. T. FalcianoIn this work we determine a lower bound to the mean value of the quantum potential for an arbitrary state. Furthermore, we derive a generalized uncertainty relation that is stronger than the RobertsonSchrödinger inequality and hence also stronger than the Heisenberg uncertainty principle. The mean value is then associated to the nonclassical part of the covariances of the momenta operator. This imposes a minimum bound for the nonclassical correlations of momenta and gives a physical characterization of the classical and semiclassical limits of quantum systems. The results obtained primarily for pure states are then generalized for density matrices describing mixed states.

Continuous monitoring of energy in quantum open systems
G. P. Martins, N. K. Bernardes, M. F. SantosWe propose a method to continually monitor the energy of a quantum system. We show that by having some previous knowledge of the system’s dynamics, but not all of it, one can use the measured energy to determine many other quantities, such as the work performed on the system, the heat exchanged between the system and a thermal reservoir, the time dependence of the Hamiltonian of the system as well as the total entropy produced by its dynamics. We have also analyzed how this method is dependent on the quality factor of the measurements employed.
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