2,443 research outputs found
Design and development of a fast scan infrared detection and measurement instrument
Infrared microscope instrument measures and plots the infrared profile of semiconductor chips, transistors and integrated circuits. Infrared analyses yields information on electrical and physical properties, enabling manufacturing improvements in semiconductor performance and reliability. Operational performance and main sections of the instrument are given
The Consistent Newtonian Limit of Einstein's Gravity with a Cosmological Constant
We derive the `exact' Newtonian limit of general relativity with a positive
cosmological constant . We point out that in contrast to the case with
, the presence of a positive in Einsteins's equations
enforces, via the condition , on the potential , a range
, within which the
Newtonian limit is valid. It also leads to the existence of a maximum mass,
. As a consequence we cannot put the boundary
condition for the solution of the Poisson equation at infinity. A boundary
condition suitably chosen now at a finite range will then get reflected in the
solution of provided the mass distribution is not spherically symmetric.Comment: Latex, 15 pages, no figures, errors correcte
Quantum Mechanical Corrections to the Schwarzschild Black Hole Metric
Motivated by quantum mechanical corrections to the Newtonian potential, which
can be translated into an -correction to the component of the
Schwarzschild metric, we construct a quantum mechanically corrected metric
assuming . We show how the Bekenstein black hole entropy
receives its logarithmic contribution provided the quantum mechanical
corrections to the metric are negative. In this case the standard horizon at
the Schwarzschild radius increases by small terms proportional to
and a remnant of the order of Planck mass emerges. We contrast these results
with a positive correction to the metric which, apart from a corrected
Schwarzschild horizon, leads to a new purely quantum mechanical horizon.Comment: 14 pages Latex, enlarged version as compared to the published on
Efficient bounds on quantum communication rates via their reduced variants
We investigate one-way communication scenarios where Bob manipulating on his
parts can transfer some sub-system to the environment. We define reduced
versions of quantum communication rates and further, prove new upper bounds on
one-way quantum secret key, distillable entanglement and quantum channel
capacity by means of their reduced versions. It is shown that in some cases
they drastically improve their estimation.Comment: 6 pages, RevTe
Dispersion relations and wave operators in self-similar quasicontinuous linear chains
We construct self-similar functions and linear operators to deduce a self-similar variant of the Laplacian operator and of the D'Alembertian wave operator. The exigence of self-similarity as a symmetry property requires the introduction of nonlocal particle-particle interactions. We derive a self-similar linear wave operator describing the dynamics of a quasicontinuous linear chain of infinite length with a spatially self-similar distribution of nonlocal interparticle springs. The self-similarity of the nonlocal harmonic particle-particle interactions results in a dispersion relation of the form of a Weierstrass-Mandelbrot function that exhibits self-similar and fractal features. We also derive a continuum approximation, which relates the self-similar Laplacian to fractional integrals, and yields in the low-frequency regime a power-law frequency-dependence of the oscillator density
Processes at High Energy pp Colliders
In this note we investigate the production of charged heavy particles via
\gaga\ fusion at high energy pp colliders. We revise previous claims that the
\gaga\ cross section is comparable to or larger than that for the corresponding
Drell-Yan process at high energies. Indeed we find that the \gaga\ contribution
to the total production cross section at pp is far below the Drell-Yan cross
section. As far as the individual elastic, semi-elastic and inelastic
contributions to the \gaga\ process are concerned we find that they are all of
the same order of magnitude.Comment: REVTEX, 12 pages, two uuencoded figures appended at the end of the
fil
About the propagation of the Gravitational Waves in an asymptotically de-Sitter space: Comparing two points of view
We analyze the propagation of gravitational waves (GWs) in an asymptotically
de-Sitter space by expanding the perturbation around Minkowski and introducing
the effects of the Cosmological Constant (), first as an additional
source (de-Donder gauge) and after as a gauge effect (-gauge). In both
cases the inclusion of the Cosmological Constant impedes the
detection of a gravitational wave at a distance larger than
, where
and f and are the frequency and
strain of the wave respectively. We demonstrate that is just a
confirmation of the Cosmic No hair Conjecture (CNC) already explained in the
literature.Comment: Accepted for publication in MPL
Data management procedures for Tiepoint Registration, pre and post processing, and ICD116
The data management procedures for tiepoint registration, pre and post processing, and "ICD116' are described. With each procedure description, the pertinent execs are listed and purposes defined. An example run of each of the 32 execs is included with user inputs identified
Gravitational Equilibrium in the Presence of a Positive Cosmological Constant
We reconsider the virial theorem in the presence of a positive cosmological
constant Lambda. Assuming steady state, we derive an inequality of the form rho
>= A (Lambda / 4 pi GN) for the mean density rho of the astrophysical object.
With a minimum at Asphere = 2, its value can increase by several orders of
magnitude as the shape of the object deviates from a spherically symmetric one.
This, among others, indicates that flattened matter distributions like e.g.
clusters or superclusters, with low density, cannot be in gravitational
equilibrium.Comment: 7 pages, no figure
- …