Does The Uncertainty Relation Determine The Quantum State?

The example of nonpositive trace-class Hermitian operator for which Robertson-Schroedinger uncertainty relation is fulfilled is presented. The partial scaling criterion of separability of multimode continuous variable system is discussed in the context of using nonpositive maps of density matrices.Comment: 11 pages, to be submitted to Physics Letters

Wigner's Problem and Alternative Commutation Relations for Quantum Mechanics

It is shown, that for quantum systems the vectorfield associated with the equations of motion may admit alternative Hamiltonian descriptions, both in the Schr\"odinger and Heisenberg pictures. We illustrate these ambiguities in terms of simple examples.Comment: Latex,14 pages,accepted by Int. Jour.Mod.Phy

Partial scaling transform of multiqubit states as a criterion of separability

The partial scaling transform of the density matrix for multiqubit states is introduced to detect entanglement of quantum states. The transform contains partial transposition as a special case. The scaling transform corresponds to partial time scaling of subsystem (or partial Planck's constant scaling) which was used to formulate recently separability criterion for continous variables.A measure of entanglement which is a generalization of negativity measure is introduced being based on tomographic probability description of spin states.Comment: 16 pages, 5 figures, submitted to J. Phys. A: Math. Ge

Development of high intensity low emission combustor for achieving flameless combustion of liquid fuels

AbstractThis paper presents the experimental and numerical results for a two stage combustor capable of achieving flameless combustion with liquid fuels for different thermal heat inputs of 20, 30, 40 and 60kW and heat release density of 5–15MW/m3. Combustion characteristics and pollutant emissions are studied for three different fuels, kerosene, diesel and gasoline. The influence of droplet diameter on pollutant emissions at all conditions is studied. The fuel and oxidizer are supplied at ambient conditions. The concept of high swirl flows has been adopted to achieve high internal recirculation rates, residence time and increased dilution of the fresh reactants in the primary combustion zone, resulting in flameless combustion mode. Air is injected through four tangential injection ports located near the bottom of the combustor and liquid fuel is injected through a centrally mounted pressure swirl injector. Computational analysis of the flow features shows that decrease in the exit port diameter of the primary chamber increases the recirculation rate of combustion products and helps in achieving the flameless combustion mode. Based on preliminary computational studies, a 30mm primary chamber exit port diameter is chosen for experimental studies. Detailed experimental investigations show that flameless combustion mode was achieved with evenly distributed combustion reaction zone and uniform temperature distribution in the combustor. Pollutant emissions of CO, NOx, CxHy are measured and compared for all operating conditions of different fuels and different thermal inputs. The acoustic emission levels are reduced by 6–8dB as combustion mode shifts from conventional mode to flameless combustion mode

A tomographic setting for quasi-distribution functions

The method of constructing the tomographic probability distributions describing quantum states in parallel with density operators is presented. Known examples of Husimi-Kano quasi-distribution and photon number tomography are reconsidered in the new setting. New tomographic schemes based on coherent states and nonlinear coherent states of deformed oscillators, including q-oscillators, are suggested. The associated identity decompositions providing Gram-Schmidt operators are explicitly given, and contact with the Agarwal-Wolf $\Omega$-operator ordering theory is made.Comment: A slightly enlarged version in which contact with the Agarwal-Wolf $\Omega$-operator ordering theory is mad

Ba Da Ba Ba Ba: I’m Stealin’ It. Vietnam and McCronyism

McDonald’s just opened its first store in Vietnam. What does this mean for Southeast Asia’s 8th most populous country