Intermolecular C-H...N and C-H...O interactions in (2S,4S,5R)-(-)-3,4-dimethyl-5-phenyl-2-(1,3-thiazol-2-yl)-1,3-oxazolidine

The title compound, C₁₄H₁₆N₂OS, prepared from (1R,2S)-(-)-ephedrine, contains the oxazolidine ring in an envelope conformation, with the nitrogen atom 0.623 (2) Å from the plane of the other four oxazolidine ring atoms. Intermolecular C--H...N and C--H...O interactions generate a two-dimensional hydrogen-bonded network, with shortest C...N and C...O distances of 3.403 (3) and 3.463 (2) Å, respectively

Quantum walks with encrypted data

In the setting of networked computation, data security can be a significant concern. Here we consider the problem of allowing a server to remotely manipulate client supplied data, in such a way that both the information obtained by the client about the server's operation and the information obtained by the server about the client's data are significantly limited. We present a protocol for achieving such functionality in two closely related models of restricted quantum computation -- the Boson sampling and quantum walk models. Due to the limited technological requirements of the Boson scattering model, small scale implementations of this technique are feasible with present-day technology.Comment: 4 pages, 2 figure

Geometry of quantum correlations in space-time

The traditional formalism of non-relativistic quantum theory allows the state of a quantum system to extend across space, but only restricts it to a single instant in time, leading to distinction between theoretical treatments of spatial and temporal quantum correlations. Here we unify the geometrical description of two-point quantum correlations in space-time. Our study presents the geometry of correlations between two sequential Pauli measurements on a single qubit undergoing an arbitrary quantum channel evolution together with two-qubit spatial correlations under a common framework. We establish a symmetric structure between quantum correlations in space and time. This symmetry is broken in the presence of non-unital channels, which further reveals a set of temporal correlations that are indistinguishable from correlations found in bipartite entangled states.Comment: 5 pages, 3 figure