3,978 research outputs found
Simpler proof of the theorem by Pusey, Barrett, and Rudolph on the reality of the quantum state
The theorem of Pusey, Barrett, and Rudolph proves that different quantum
states describe different physical realities. Their proof is based on the
construction of entanglement measurement bases of two, and more than two qbits.
In this note, I show that a two-qubit entanglement base is sufficient for a
general proof.Comment: 5 pages, 2 figure
N-component Bose-Einstein Condensate in an Optical Lattice: Destruction of the Condensate and Quasiparticle Properties
We present a model of N-component hard-core bosons on a lattice. The limit N
to infinity can be solved exactly. A saddle point approximation leads to a 1/N
expansion and allows the calculation of physical quantities like the density of
the condensate, the correlation between the components and the density-density
correlation function and the correlation between different components. We find
a superfluid phase with a tendency towards a Mott insulator at high densities
and finite N.Comment: 8 pages, 3 figures, small changes, error corrected in Appendi
Life sciences Spacelab Mission Development test 3 (SMD 3) data management report
Development of a permanent data system for SMD tests was studied that would simulate all elements of the shuttle onboard, telemetry, and ground data systems that are involved with spacelab operations. The onboard data system (ODS) and the ground data system (GDS) were utilized. The air-to-ground link was simulated by a hardwired computer-to-computer interface. A patch board system was used on board to select experiment inputs, and the downlink configuration from the ODS was changed by a crew keyboard entry to support each experiment. The ODS provided a CRT display of experiment parameters to enable the crew to monitor experiment performance. An onboard analog system, with recording capability, was installed to handle high rate data and to provide a backup to the digital system. The GDS accomplished engineering unit conversion and limit sensing, and provided realtime parameter display on CRT's in the science monitoring area and the test control area
A brief description of the Medical Information Computer System (MEDICS)
The Medical Information Computer System (MEDICS) is a time shared, disk oriented minicomputer system capable of meeting storage and retrieval needs for the space- or non-space-related applications of at least 16 simultaneous users. At the various commercially available low cost terminals, the simple command and control mechanism and the generalized communication activity of the system permit multiple form inputs, real-time updating, and instantaneous retrieval capability with a full range of options
Aerodynamic characteristics determined during development of the Apollo launch escape vehicle configuration
Aerodynamic characteristics determined during development of Apollo launch escape vehicle configuration in wind tunnel test
Aerodynamic loads on deployed canard surfaces and rocket nose section of the Apollo launch escape vehicle
Aerodynamic loads on deployed canard surfaces and rocket nose section of Apollo launch escape vehicl
Wind-tunnel investigation of the aerodynamic pressures on the Apollo command module configuration
Wind tunnel study of aerodynamic pressures on Apollo command module configuratio
Dynamical Mean Field Theory for the Bose-Hubbard Model
The dynamical mean field theory (DMFT), which is successful in the study of
strongly correlated fermions, was recently extended to boson systems [Phys.
Rev. B {\textbf 77}, 235106 (2008)]. In this paper, we employ the bosonic DMFT
to study the Bose-Hubbard model which describes on-site interacting bosons in a
lattice. Using exact diagonalization as the impurity solver, we get the DMFT
solutions for the Green's function, the occupation density, as well as the
condensate fraction on a Bethe lattice. Various phases are identified: the Mott
insulator, the Bose-Einstein condensed (BEC) phase, and the normal phase. At
finite temperatures, we obtain the crossover between the Mott-like regime and
the normal phase, as well as the BEC-to-normal phase transition. Phase diagrams
on the plane and on the plane are
produced ( is the scaled hopping amplitude). We compare our results
with the previous ones, and discuss the implication of these results to
experiments.Comment: 11 pages, 8 figure
Interacting bosons in an optical lattice: Bose-Einstein condensates and Mott insulator
A dense Bose gas with hard-core interaction is considered in an optical
lattice. We study the phase diagram in terms of a special mean-field theory
that describes a Bose-Einstein condensate and a Mott insulator with a single
particle per lattice site for zero as well as for non-zero temperatures. We
calculate the densities, the excitation spectrum and the static structure
factor for each of these phases.Comment: 17 pages, 5 figures; 1 figure added, typos remove
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