36,833 research outputs found
Some studies on quantum equivalents of non-commutative operators via commutating eigenvalue relation: PT-symmetry
We study quantum equivalents of non-commutative operators in quantum
mechanics. Any matrix "" satisfying the non-commuting relation
with "", can be used via to reproduce eigenvalues of "". This
universality relation is also equally valid for any matrix in any branch of
physical or social science and also any operator involving co-ordinate or
momentum. Pictorially this is represented in fig. 1. Many interesting
models including logarithmic potential have been considered.Comment: Since new submissions are not allowed, I have replaced my previous
article, which may kindly be allowe
Measuring the Double Layer Capacitance of Electrolytes with Varied Concentrations
When electric potentials are applied from an electrolytic fluid to a metal, a double layer capacitor, Cdl, develops at the interface. The layer directly at the interface is called the Stern layer and has a thickness equal to roughly the size of the ions in the fluid. The next layer, the diffuse layer, arises from the gathering of like charges in the Stern layer. This layer is the distance needed for ionic concentrations to match the bulk fluid. This distance, called the Debye length, λ, depends on the square root of the electrolyte concentration. To study the properties of the diffuse layer, we measure C using different concentrations of electrolyte solutions in a cylindrical capacitor system we machined
Uncertainties and shortcomings of ground surface temperature histories derived from inversion of temperature logs
Analysing borehole temperature data in terms of ground surface history can
add useful information to reconstructions of past climates. Therefore, a
rigorous assessment of uncertainties and error sources is a necessary
prerequisite for the meaningful interpretation of such ground surface
temperature histories. This study analyses the most prominent sources of
uncertainty. The diffusive nature of the process makes the inversion relatively
robust against incomplete knowledge of the thermal diffusivity. Similarly the
influence of heat production is small. It turns out that for investigations of
the last 1000 to 100000 years the maximum depth of the temperature log is
crucial. More than 3000 m are required for an optimal inversion.
Reconstructions of the last one or two millennia require only modestly deep
logs (>300 m) but suffer severely from noisy data.Comment: 28 pages, 18 figure, 3 table
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