3,366 research outputs found
Operator algebra quantum homogeneous spaces of universal gauge groups
In this paper, we quantize universal gauge groups such as SU(\infty), as well
as their homogeneous spaces, in the sigma-C*-algebra setting. More precisely,
we propose concise definitions of sigma-C*-quantum groups and sigma-C*-quantum
homogeneous spaces and explain these concepts here. At the same time, we put
these definitions in the mathematical context of countably compactly generated
spaces as well as C*-compact quantum groups and homogeneous spaces. We also
study the representable K-theory of these spaces and compute it for the quantum
homogeneous spaces associated to the universal gauge group SU(\infty).Comment: 14 pages. Merged with [arXiv:1011.1073
Modeling of convection phenomena in Bridgman-Stockbarger crystal growth
Thermal convection phenomena in a vertically oriented Bridgman-Stockbarger apparatus were modeled by computer simulations for different gravity conditions, ranging from earth conditions to extremely low gravity, approximate space conditions. The modeling results were obtained by the application of a state-of-the art, transient, multi-dimensional, completely densimetrically coupled, discrete-element computational model which was specifically developed for the simulation of flow, temperature, and species concentration conditions in two-phase (solid-liquid) systems. The computational model was applied to the simulation of the flow and the thermal conditions associated with the convection phenomena in a modified Germanium-Silicon charge enclosed in a stationary fused-silica ampoule. The results clearly indicated that the gravitational field strength influences the characteristics of the coherent vortical flow patterns, interface shape and position, maximum melt velocity, and interfacial normal temperature gradient
Analysis of Foreign and Domestic Investment on Economic Growth in Nigeria (1980-2013)
Several factors have hampered economic growth in Nigeria, though there has been improvement in the recent times. Nevertheless, it remains fragile and is not strong enough to significantly reduce the prevailing level of poverty in the country. Against this backdrop, the study investigates the relationship between foreign and domestic investment on Economic growth in Nigeria, during the period 1980-2013, using Vector Error Correction Model (VECM). The study finds out that foreign and domestic investment have a strong influence both in short and long run, on the economic growth of Nigeria. The result shows unidirectional long-run causality between domestic investments to real GDP in Nigeria. Also, there is unidirectional long-run causality between exchange rate and real GDP in Nigeria. The result implies that change in current GDP is better explained by domestic investment and exchange rate rather than national income, foreign direct investment and credit to private sector. Hence, the government may encourage foreign investors to invest in the high risk areas, where the domestic investment lacks the technology and experiences needed
Corruption and Economic Growth in Nigeria (1980-2013)
Corruption is as aged as the existence of man and it exists in all sphere of human life. The persistency of corruption erodes the social economic value of a nation. The study investigates the relationship between corruption and economic growth in Nigeria, in the period 1980-2013, using the VAR analysis. The study finds the existence of long-term relationship between corruption and unemployment growth on the economic growth of Nigeria. Also, the study found no short-term relationship in corruption and unemployment on economic growth. Hence, the result in the analysis shows that corruption positively has a strong influence on the output of Nigeria. So the rise in growth rate experienced in Nigeria is influenced by high corruption rate in the country, which is making the few rich to be richer, eradicating the middle class and making the poor to be poorer. Therefore, there is a need to develop political will to prosecute anyone found guilty of corruption irrespective of their position, tribe, religion or party affiliation. Such a punishment would also serve as a deterrent to others and help improve real economic growth and development
Quantum planes and quantum cylinders from Poisson homogeneous spaces
Quantum planes and a new quantum cylinder are obtained as quantization of
Poisson homogeneous spaces of two different Poisson structures on classical
Euclidean group E(2).Comment: 13 pages, plain Tex, no figure
Polaronic transport induced by competing interfacial magnetic order in a LaCaMnO/BiFeO heterostructure
Using ultrafast optical spectroscopy, we show that polaronic behavior
associated with interfacial antiferromagnetic order is likely the origin of
tunable magnetotransport upon switching the ferroelectric polarity in a
LaCaMnO/BiFeO (LCMO/BFO) heterostructure. This is
revealed through the difference in dynamic spectral weight transfer between
LCMO and LCMO/BFO at low temperatures, which indicates that transport in
LCMO/BFO is polaronic in nature. This polaronic feature in LCMO/BFO decreases
in relatively high magnetic fields due to the increased spin alignment, while
no discernible change is found in the LCMO film at low temperatures. These
results thus shed new light on the intrinsic mechanisms governing
magnetoelectric coupling in this heterostructure, potentially offering a new
route to enhancing multiferroic functionality
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