Boson bunching is among the most remarkable features of quantum physics. A celebrated example in optics Hong–Ou–Mandel effect, where two photons arises from a destructive interference between trajectories they both either cross beamsplitter or are reflected. This effect takes its roots indistinguishability identical photons. Hence, it generally admitted—and experimentally verified—that vanishes...

We report the possibility of completely destructive interference of three indistinguishable photons on a three port device providing a generalisation of the well known Hong-Ou-Mandel interference of two indistinguishable photons on a two port device. Our analysis is based on the underlying mathematical framework of SU(3) transformations rather than SU(2) transformations. We show the completely ...

A manifestly covariant relativistic statistical mechanics of the system of N indistinguishable events with motion in space-time parametrized by an invariant “historical time” τ is considered. The relativistic mass distribution for such a system is obtained from the equilibrium solution of the generalized relativistic Boltzmann equation by integration over angular and hyperbolic angular variable...

We investigate the problem of determining a set S of k indistinguishable integers in the range [1, n]. The algorithm is allowed to query an integer q ∈ [1, n], and receive a response comparing this integer to an integer randomly chosen from S. The algorithm has no control over which element of S the query q is compared to. We show tight bounds for this problem. In particular, we show that in th...

Deciding inseparability of description logic knowledge bases (KBs) with respect to conjunctive queries is fundamental for many KB engineering and maintenance tasks including versioning, module extraction, knowledge exchange and forgetting. We study the combined and data complexity of this inseparability problem for fragments of Horn-ALCHI, including the description logics underpinning OWL 2 QL ...

We determine the degree of entanglement for two indistinguishable particles based on the tensor product structure, which is a framework for emphasizing entanglement founded on observational quantities. Our theory connects the canonical entanglement and entanglement based on occupation number for two fermions and for two bosons and shows that the entanglement measure, based on linear entropy, is...

We report the results of coincidence counting experiments at the output, of a Michelson interferometer using the zero-phonon-line emission of a single molecule at 1.4 K. Under continuous wave excitation, we observe the absence of coincidence counts as an indication of two-photon interference. This corresponds to the observation of Hong-Ou-Mandel correlations and proves the suitability of the ze...

Results on the observational indistinguishability of spacetimes demonstrate the impossibility of determining by deductive inference which is our spacetime, no matter how extensive a portion of the spacetime is observed. These results do not illustrate an underdetermination of theory by evidence, since they make no decision between competing theories and they make little contact with the inducti...