238 research outputs found
Possible Market Implications of Unisex Insurance Pricing
The main reason for different insurance premiums and benefits is the use of different statistically proven risk factors in actuarial calculations for individuals. Basing its ruling on European Union Directive 2004/113/EC (the Gender Directive), the European Court of Justice on 1 March 2011 concluded that any gender-based discrimination is prohibited, so gender equality in the European Union (EU) must be ensured from 21 December 2012. The ruling definitively banning the use of the gender criterion in actuarial calculations for individual prices may have important consequences for the insurance industry and customers in the EU. In this short text, a number of implications are discussed. Possible consumer behaviour and potential responses from market players are outlined as well as possible further regulatory interventions. The implications of the definitive ban on gender based discrimination are extensive for the insurance industry and may have a strong economic and legal impact on the individual product offering and pricing.
https://www.genevaassociation.org/media/887422/ga2014-ie70-schmeiser.pd
Variation of elastic scattering across a quantum well
The Drude scattering times of electrons in two subbands of a parabolic
quantum well have been studied at constant electron sheet density and different
positions of the electron distribution along the growth direction. The
scattering times obtained by magnetotransport measurements decrease as the
electrons are displaced towards the well edges, although the lowest-subband
density increases. By comparing the measurements with calculations of the
scattering times of a two-subband system, new information on the location of
the relevant scatterers and the anisotropy of intersubband scattering is
obtained. It is found that the scattering time of electrons in the lower
subband depends sensitively on the position of the scatterers, which also
explains the measured dependence of the scattering on the carrier density. The
measurements indicate segregation of scatterers from the substrate side towards
the quantum well during growth.Comment: 4 pages, 4 figure
Flux of Atmospheric Neutrinos
Atmospheric neutrinos produced by cosmic-ray interactions in the atmosphere
are of interest for several reasons. As a beam for studies of neutrino
oscillations they cover a range of parameter space hitherto unexplored by
accelerator neutrino beams. The atmospheric neutrinos also constitute an
important background and calibration beam for neutrino astronomy and for the
search for proton decay and other rare processes. Here we review the literature
on calculations of atmospheric neutrinos over the full range of energy, but
with particular attention to the aspects important for neutrino oscillations.
Our goal is to assess how well the properties of atmospheric neutrinos are
known at present.Comment: 68 pages, 26 figures. With permission from the Annual Review of
Nuclear & Particle Science. Final version of this material is scheduled to
appear in the Annual Review of Nuclear & Particle Science Vol. 52, to be
published in December 2002 by Annual Reviews (http://annualreviews.org
Theory of Incompressible States in a Narrow Channel
We report on the properties of a system of interacting electrons in a narrow
channel in the quantum Hall effect regime. It is shown that an increase in the
strength of the Coulomb interaction causes abrupt changes in the width of the
charge-density profile of translationally invariant states. We derive a phase
diagram which includes many of the stable odd-denominator states as well as a
novel fractional quantum Hall state at lowest half-filled Landau level. The
collective mode evaluated at the half-filled case is strikingly similar to that
for an odd-denominator fractional quantum Hall state.Comment: 4 pages, REVTEX, and 4 .ps file
Permafrost degradation at two monitored palsa mires in north-west Finland
Palsas and peat plateaus are expected to disappear from many regions, including Finnish Lapland. However, detailed long-term monitoring data of the degradation process on palsas are scarce. Here, we present the results of the aerial photography time series analysis (1959–2021), annual real-time kinematic (RTK) GNSS and active layer monitoring (2007–2021), and annual unoccupied aerial system surveys (2016–2021) at two palsa sites (Peera and Laassaniemi, 68∘ N) located in north-west Finland. We analysed temporal trends of palsa degradation and their relation to climate using linear regression. At both sites, the decrease in palsa area by −77 % to −90 % since 1959 and height by −16 % to −49 % since 2007 indicate substantial permafrost degradation throughout the study periods. The area loss rates are mainly connected to winter air temperature changes at Peera and winter precipitation changes at Laassaniemi. The active layer thickness (ALT) has varied annually between 2007 and 2021 with no significant trend and is related mainly to the number of very warm days during summer, autumn rainfall of previous year, and snow depths at Peera. At Laassaniemi, the ALT is weakly related to climate and has been decreasing in the middle part of the palsa during the past 8 years despite the continuous decrease in palsa volume. Our findings imply that the ALT in the inner parts of palsas do not necessarily reflect the overall permafrost conditions and underline the importance of surface position monitoring alongside the active layer measurements. The results also showed a negative relationship between the ALT and snow cover onset, indicating the complexity of climate–permafrost feedbacks in palsa mires.</p
Spectral Properties of Three Dimensional Layered Quantum Hall Systems
We investigate the spectral statistics of a network model for a three
dimensional layered quantum Hall system numerically. The scaling of the
quantity is used to determine the critical exponent for
several interlayer coupling strengths. Furthermore, we determine the level
spacing distribution as well as the spectral compressibility at
criticality. We show that the tail of decays as with
and also numerically verify the equation
, where is the correlation dimension and the
spatial dimension.Comment: 4 pages, 5 figures submitted to J. Phys. Soc. Jp
The transverse magnetoresistance of the two-dimensional chiral metal
We consider the two-dimensional chiral metal, which exists at the surface of
a layered, three-dimensional sample exhibiting the integer quantum Hall effect.
We calculate its magnetoresistance in response to a component of magnetic field
perpendicular to the sample surface, in the low temperature, but macroscopic,
regime where inelastic scattering may be neglected. The magnetoresistance is
positive, following a Drude form with a field scale,
, given by the transverse field strength at which
one quantum of flux, , passes through a rectangle with sides set by the
layer-spacing, , and the elastic mean free path, .
Experimental measurement of this magnetoresistance may therefore provide a
direct determination of the elastic mean free path in the chiral metal.Comment: submitted to Phys Rev
Upper bounds on the density of states of single Landau levels broadened by Gaussian random potentials
We study a non-relativistic charged particle on the Euclidean plane R^2
subject to a perpendicular constant magnetic field and an R^2-homogeneous
random potential in the approximation that the corresponding random Landau
Hamiltonian on the Hilbert space L^2(R^2) is restricted to the eigenspace of a
single but arbitrary Landau level. For a wide class of Gaussian random
potentials we rigorously prove that the associated restricted integrated
density of states is absolutely continuous with respect to the Lebesgue
measure. We construct explicit upper bounds on the resulting derivative, the
restricted density of states. As a consequence, any given energy is seen to be
almost surely not an eigenvalue of the restricted random Landau Hamiltonian.Comment: 16 pages, to appear in "Journal of Mathematical Physics
A Fermi Fluid Description of the Half-Filled Landau Level
We present a many-body approach to calculate the ground state properties of a
system of electrons in a half-filled Landau level. Our starting point is a
simplified version of the recently proposed trial wave function where one
includes the antisymmetrization operator to the bosonic Laughlin state. Using
the classical plasma analogy, we calculate the pair-correlation function, the
static structure function and the ground state energy in the thermodynamic
limit. These results are in good agreement with the expected behavior at
.Comment: 4 pages, REVTEX, and 4 .ps file
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