1,676 research outputs found
Casimir Energy for a Wedge with Three Surfaces and for a Pyramidal Cavity
Casimir energy calculations for the conformally coupled massless scalar field
for a wedge defined by three intersecting planes and for a pyramid with four
triangular surfaces are presented. The group generated by reflections are
employed in the formulation of the required Green functions and the wave
functions.Comment: Latex, 9 page
Realizations for Kepler and Oscillator Potentials and q-Canonical Transformations
The realizations of the Lie algebra corresponding to the dynamical symmetry
group SO(2,1) of the Kepler and oscillator potentials are q-deformed. The
q-canonical transformation connecting two realizations is given and a general
definition for q-canonical transformation is deduced. q-Schr\"{o}dinger
equation for a Kepler like potential is obtained from the q-oscillator
Schr\"{o}dinger equation. Energy spectrum and the ground state wave function
are calculated.Comment: 12 pages, Latex twice, (Comparison with the other approaches and some
refs. added. The version which will appear in J. Phys. A
Implications of Geographic Information System in Mapping Solid Waste Collection Points in New Owerri, Imo State
The unsanitary condition in which solid waste is temporarily dumped and disposed of has generated environmental concern through pollutions and health hazards. This calls for a need to map out suitable collection points and disposal point for effective and efficient management of solid waste to promote hygienic environment. Therefore, GIS offers solution in this regard as a decision support system for most suitable site selection. Consequently, different layers (roads, stream and land use) were created to serve the purpose of manipulation and analyses to procure most suitable site for collection point of solid waste generated in New Owerri, Imo State using Arc view 3.2a software
Macroscopic Quantum Tunneling of a Bose Condensate
We study, by means of a variational method, the stability of a condensate in
a magnetically trapped atomic Bose gas with a negative scattering length and
find that the condensate is unstable in general. However, for temperatures
sufficiently close to the critical temperature the condensate turns out to be
metastable. For that case we determine in the usual WKB approximation the decay
rate of the condensate due to macroscopic quantum fluctuations. When
appropriate, we also calculate the decay rate due to thermal fluctuations. An
important feature of our approach is that (nonsingular) phase fluctuations of
the condensate are taken into account exactly.Comment: Invited paper for the Journal of Statistical Physic
Boundary Shape and Casimir Energy
Casimir energy changes are investigated for geometries obtained by small but
arbitrary deformations of a given geometry for which the vacuum energy is
already known for the massless scalar field. As a specific case, deformation of
a spherical shell is studied. From the deformation of the sphere we show that
the Casimir energy is a decreasing function of the surface to volume ratio. The
decreasing rate is higher for less smooth deformations.Comment: 12 page
Are Leaf Traits Stable Enough to Rank Native Grasses in Contrasting Growth Conditions?
The growing interest in classifying species in response groups relating to variations in environmental factors has triggered the search for functional traits that express differences in ecological behaviour among plant species (Lavorel & Garnier, 2002). Specific leaf area (SLA) and leaf dry matter content (LDMC) reflect a fundamental trade-off in plant functioning between a fast growth rate (high SLA, low LDMC species) and nutrient conservation (low SLA, high LDMC species). This study aimed to analyse the stability of ranking native grasses by SLA and LDMC values under different plant growing conditions
Exact propagators for atom-laser interactions
A class of exact propagators describing the interaction of an -level atom
with a set of on-resonance -lasers is obtained by means of the Laplace
transform method. State-selective mirrors are described in the limit of strong
lasers. The ladder, V and configurations for a three-level atom are
discussed. For the two level case, the transient effects arising as result of
the interaction between both a semi-infinite beam and a wavepacket with the
on-resonance laser are examined.Comment: 13 pages, 6 figure
Extraction of isoflavones from different raw sources using natural deep eutectic solvents
This research was partially supported by RFBR 17-03-00641 and the Ministry of Education of the Russian Federation within the framework of the basic part of the state task, Project No. 4.9514.2017 / 8.9
- …