1,444 research outputs found
DEATH TAXES ON COMPLETED TRANSFERS INTER VIVOS
The subjection of transfers inter vivas to the death tax under each of the above categories has been based upon the proposition that, for a transfer inter vivas properly to be subject to the death tax, it must bear some reasonable relationship to transfers at death either by will or under the law relating to intestacy. This rule has been applied both in problems of statutory construction and in problems of constitutionality. The recent decision of the United States Supreme Court in Helvering v. Bullard seems to have abandoned this test for the inclusion of transfers inter vivas within the scope of the death tax, so far as the federal death tax is concerned. It is the purpose here to study the present status of the law relating to death taxes upon transfers inter vivas, with particular reference to the taxation of such transfers complete when made, as upheld by this Supreme Court decision
Signatures of Radiation Reaction in Ultra-Intense Laser Fields
We discuss radiation reaction effects on charges propagating in ultra-intense
laser fields. Our analysis is based on an analytic solution of the
Landau-Lifshitz equation. We suggest to measure radiation reaction in terms of
a symmetry breaking parameter associated with the violation of null translation
invariance in the direction opposite to the laser beam. As the Landau-Lifshitz
equation is nonlinear the energy transfer within the pulse is rather sensitive
to initial conditions. This is elucidated by comparing colliding and fixed
target modes in electron laser collisions.Comment: 8 pages, 6 figure
Persistent random walk on a one-dimensional lattice with random asymmetric transmittances
We study the persistent random walk of photons on a one-dimensional lattice
of random asymmetric transmittances. Each site is characterized by its
intensity transmittance t (t') for photons moving to the right (left)
direction. Transmittances at different sites are assumed independent,
distributed according to a given probability density Distribution. We use the
effective medium approximation and identify two classes of probability density
distribution of transmittances which lead to the normal diffusion of photons.
Monte Carlo simulations confirm our predictions.Comment: 7 pages, submitted to Phys. Rev.
Performance and selection of winter durum wheat genotypes in different European conventional and organic fields
Sustainability is a key factor for the future of agriculture. Productivity in agriculture has more than tripled in developed countries since the 1950s. Beyond the success of plant breeding, the increased use of inorganic fertilizers, application of pesticides, and spread of irrigation also contributed to this success. However, impressive yield increases started to decline in the 1980s because of the lack of sustainability. One of the most beneficial ways to increase sustainability is organic agriculture. In such agro-ecosystem-based holistic production systems the prerequisite of successful farming is the availability of crop genotypes that perform well. However, selection of winter durum wheat for sub-optimal growing conditions is still mainly neglected, and the organic seed market also lacks of information on credibly tested winter durum varieties suitable for organic agriculture
Validation of a new tribological test bench for lightweight hydraulic components
The presented paper deals with tribological contacts in “lightweight” hydraulic pumps. One approach for the mass reduction of hydraulic systems is the material substitution. According to this strategy, steel-components are replaced with polymeric material or hybrid design components. The consequences of this material substitution are tribological changes of the contact pairings. Hence, there is research necessary on the tribological behavior of the specific contacts between polymers or hybrid components. For the characterization of these tribological contacts, a test bench was developed. With this test bench the analysis of the tribological behavior of the contact between cylinder and control plate in the axial piston variable pump is possible. A description of the modeling and a validation of the test bench are presented in the this paper. The result is, the test bench indicates good measurement result quality. In addition a cooling system is necessary to guarantee a constant test fluid temperature
Rotation of a spheroid in a simple shear at small Reynolds number
We derive an effective equation of motion for the orientational dynamics of a
neutrally buoyant spheroid suspended in a simple shear flow, valid for
arbitrary particle aspect ratios and to linear order in the shear Reynolds
number. We show how inertial effects lift the degeneracy of the Jeffery orbits
and determine the stabilities of the log-rolling and tumbling orbits at
infinitesimal shear Reynolds numbers. For prolate spheroids we find stable
tumbling in the shear plane, log-rolling is unstable. For oblate particles, by
contrast, log-rolling is stable and tumbling is unstable provided that the
aspect ratio is larger than a critical value. When the aspect ratio is smaller
than this value tumbling turns stable, and an unstable limit cycle is born.Comment: 25 pages, 5 figure
Self-energy of a scalar charge near higher-dimensional black holes
We study the problem of self-energy of charges in higher dimensional static
spacetimes. Application of regularization methods of quantum field theory to
calculation of the classical self-energy of charges leads to model-independent
results. The correction to the self-energy of a scalar charge due to the
gravitational field of black holes of the higher dimensional
Majumdar-Papapetrou spacetime is calculated exactly. It proves to be zero in
even dimensions, but it acquires non-zero value in odd dimensional spacetimes.
The origin of the self-energy correction in odd dimensions is similar to the
origin the conformal anomalies in quantum field theory in even dimensional
spacetimes.Comment: 9 page
Temperature Profiles in Hamiltonian Heat Conduction
We study heat transport in the context of Hamiltonian and related stochastic
models with nearest-neighbor coupling, and derive a universal law for the
temperature profiles of a large class of such models. This law contains a
parameter , and is linear only when . The value of
depends on energy-exchange mechanisms, including the range of motion of tracer
particles and their times of flight.Comment: Revised text, same results Second revisio
Observation of light dragging in rubidium vapor cell
We report on the experimental demonstration of light dragging effect due to
atomic motion in a rubidium vapor cell. We found that the minimum group
velocity is achieved for light red-shifted from the center of the atomic
resonance, and that the value of this shift increases with decreasing group
velocity, in agreement with the theoretical predictions by Kocharovskaya,
Rostovtsev, and Scully [Phys. Rev. Lett. {\bf 86}, 628 (2001)].Comment: 4 pages 4 figures, submitted to PR
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