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Bell Nonlocality
Nonlocality was discovered by John Bell in 1964, in the context of the debates about quantum theory, but is a phenomenon that can be studied in its own right. Its observation proves that measurements
Device-independent quantum key distribution secure against collective attacks
TLDR
This proof exploits the full structure of quantum theory, but only holds against collective attacks, where the eavesdropper is assumed to act on the quantum systems of the honest parties independently and identically in each round of the protocol.
Device-independent security of quantum cryptography against collective attacks.
TLDR
The main result is a tight bound on the Holevo information between one of the authorized parties and the eavesdropper, as a function of the amount of violation of a Bell-type inequality.
Detection-loophole-free test of quantum nonlocality, and applications.
TLDR
A source of entangled photons is presented that violates a Bell inequality free of the "fair-sampling" assumption, and is used to generate "device-independent" private quantum random numbers at rates over 4 orders of magnitude beyond previous experiments.
Closing the detection loophole in Bell experiments using qudits.
We show that the detection efficiencies required for closing the detection loophole in Bell tests can be significantly lowered using quantum systems of dimension larger than two. We introduce a
Self-testing quantum random number generator.
TLDR
This work presents a protocol for self-testing quantum random number generation, in which the user can monitor the entropy in real time, and guarantees continuous generation of high quality randomness, without the need for a detailed characterization of the devices.
Connection between Bell nonlocality and Bayesian game theory.
TLDR
There is a deep connection between Bell nonlocality and Bayesian games, and that the same concepts appear in both fields, and some of these strategies represent equilibrium points, leading to the notion of quantum/no-signalling Nash equilibrium.
Measuring small longitudinal phase shifts: weak measurements or standard interferometry?
TLDR
It is shown that standard interferometry greatly outperforms weak measurements in a scenario involving a purely real weak value, but an interferometric scheme based on a purely imaginary weak value combined with a frequency-domain analysis may have the potential to outperform standardInterferometry by several orders of magnitude.
Device-independent tests of classical and quantum dimensions.
TLDR
A general formalism for tackling the problem of testing the dimensionality of classical and quantum systems in a "black-box" scenario is developed and the concept of quantum dimension witnesses to arbitrary quantum systems is generalized, allowing one to derive lower bounds on the classical dimension necessary to reproduce given measurement data.
Guess your neighbor's input: a multipartite nonlocal game with no quantum advantage.
TLDR
The results suggest that quantum correlations might obey a generalization of the usual no-signaling conditions in a multipartite setting, and identify parts of the boundary between quantum and postquantum correlations of maximal dimension.
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