156 research outputs found
To Bin or Not To Bin: Decorrelating the Cosmic Equation of State
The physics behind the acceleration of the cosmic expansion can be elucidated
through comparison of the predictions of dark energy equations of state to
observational data. In seeking to optimize this, we investigate the advantages
and disadvantages of using principal component analysis, uncorrelated
bandpowers, and the equation of state within redshift bins. We demonstrate that
no one technique is a panacea, with tension between clear physical
interpretation from localization and from decorrelated errors, as well as model
dependence and form dependence. Specific lessons include the critical role of
proper treatment of the high redshift expansion history and the lack of a
unique, well defined signal-to-noise or figure of merit.Comment: 26 pages, 28 figure
Calibrating Dark Energy
Exploring the diversity of dark energy dynamics, we discover a calibration
relation, a uniform stretching of the amplitude of the equation of state time
variation with scale factor. This defines homogeneous families of dark energy
physics. The calibration factor has a close relation to the standard time
variation parameter w_a, and we show that the new, calibrated w_a describes
observables, i.e. distance and Hubble parameter as a function of redshift,
typically to an accuracy level of 10^{-3}. We discuss implications for figures
of merit for dark energy science programs.Comment: 9 pages, 10 figure
CMB Lensing Constraints on Neutrinos and Dark Energy
Signatures of lensing of the cosmic microwave background radiation by
gravitational potentials along the line of sight carry with them information on
the matter distribution, neutrino masses, and dark energy properties. We
examine the constraints that Planck, PolarBear, and CMBpol future data,
including from the B-mode polarization or the lensing potential, will be able
to place on these quantities. We simultaneously fit for neutrino mass and dark
energy equation of state including time variation and early dark energy
density, and compare the use of polarization power spectra with an optimal
quadratic estimator of the lensing. Results are given as a function of
systematics level from residual foreground contamination. A realistic CMBpol
experiment can effectively constrain the sum of neutrino masses to within 0.05
eV and the fraction of early dark energy to 0.002. We also present a
surprisingly simple prescription for calculating dark energy equation of state
constraints in combination with supernova distances from JDEM.Comment: 18 pages, 14 figures. Small changes made to match version to be
published in Phys. Rev.
Informelle Pflege und Arbeitsmarktpartizipation
Der demografische Wandel und die damit einhergehende Alterung der Gesellschaft sowie Reduktion der Erwerbsbevölkerung stellen große gesellschaftliche Herausforderungen dar. Der Bedarf an familiärer Pflege wird infolge der zunehmenden Alterung der Gesellschaft weiter steigen. Die Angehörigenpflege wird dabei aufgrund des traditionellen Rollenverständnisses in der Regel von Frauen übernommen. Da dem Rückgang der Erwerbsbevölkerung u.a. mit einer höheren Frauenerwerbsquote gegen gesteuert werden soll, kommt es zwangsläufig zu einem Konflikt zwischen erhöhtem Pflegebedarf und verminderter Erwerbsbevölkerung. Vor diesem Hintergrund stellt sich daher die Frage, inwiefern sich Erwerbsbeteiligung und informelle Pflege miteinander vereinbaren lassen. Ziel dieser Untersuchung ist die Analyse der Effekte der Erbringung informeller Pflegeleistungen auf die Arbeitsmarktpartizipation von Männern und Frauen. Für die Untersuchung dieser Fragestellung werden Routinedaten der Techniker Krankenkasse herangezogen. Zur Verfügung steht ein Paneldatensatz für die Jahre 2007-2009 mit ca. 16 Mio. Beobachtungen. Um den Einfluss der Erbringung informeller Pflegeleistungen auf die Arbeitsmarktpartizipation zu identifizieren, werden lineare Modelle geschätzt, in denen für zeitinvariante Heterogenität kontrolliert wird. Während die Ergebnisse für Männer durchweg insignifikant sind, ist für Frauen ein signifikant positiver Zusammenhang zwischen der Erbringung informeller Pflegeleistungen und sowohl lang- als auch kurzfristiger Arbeitslosigkeit zu beobachten. Um über die Auswirkungen von informeller Pflege auf die Arbeitsmarktpartizipation zu diskutieren, ist es notwendig jegliche Opportunitätskosten zu berücksichtigen. Die aktuellen Pflegegesetze sehen zwar eine finanzielle Entschädigung für Pflegende vor, beziehen aber nicht die Reduzierung oder Niederlegung der Arbeit und das damit einhergehende verringerte Einkommen des Pflegenden in ausreichendem Maße mit ein. Eine Möglichkeit, um Pflegende zu entlasten, wäre die Flexibilisierung von Arbeitszeiten.Due to the demographic change and the concomitant ageing of society, the labor force will reduce substantially. In order to mitigate the consequences of the demographic change the European Council aims at a higher labor force participation of women. Simultaneously, the demand for informal care will increase due to the ageing of society. Owing to the traditional understanding of women's role, mainly females engage in informal care. Attempting to counteract the reduction of labor force by means of increasing women’s labor force participation, there occurs a conflict between rising demand for informal care and decreasing labor force. Based on this background, the compatibility of labor market participation and informal care should be contemplated critically. The objective of this study is to analyze the effects of informal care on labor market participation of men and women. This study uses administrative data of Germany’s largest sickness fund, the Techniker Krankenkasse, to analyze the above-mentioned issue. The data set contains more than 16 million observations for 2007-2009. In order to identify the effects of informal care on labor force participation, linear regression models are estimated in which is controlled for time-invariant heterogeneity. For men the results are not significant. The results for women illustrate a significant positive relationship between informal care and long-term as well as short-term unemployment. In order to discuss the effects of informal care on labor force participation, it is essential to take all opportunity costs into account. The current care laws include a financial compensation for informal caregivers, but they do not take the reduction or termination of employment and the associated reduced income into consideration. A transition to more flexible working hours could possibly relieve informal caregivers
Signature of odd-frequency pairing correlations induced by a magnetic interface
We investigate the mutual proximity effect in a normal metal contacted to a
superconductor through a magnetic interface. Analytical and self-consistent
numerical results are presented, and we consider both the diffusive and
ballistic regimes. We focus on the density of states in both the normal and
superconducting region, and find that the presence of spin-dependent
phase-shifts occurring at the interface qualitatively modifies the density of
states. In particular, we find that the proximity-induced pairing amplitudes in
the normal metal region undergo a conversion at the Fermi level from pure
even-frequency to odd-frequency. Above a critical value of the interface
spin-polarization (or, equivalently, for fixed interface spin-polarization,
above a critical interface resistance), only odd frequency correlations remain.
This is accompanied by the replacement of the familiar proximity minigap or
pseudogap in the normal layer by an enhancement of the density of states above
its normal state value for energies near the chemical potential. The robustness
of this effect towards inelastic scattering, impurity scattering, and the
depletion of the superconducting order parameter close to the interface is
investigated. We also study the inverse proximity effect in the diffusive
limit. We find that the above-mentioned conversion persists also for thin
superconducting layers comparable in size to the superconducting coherence
length , as long as the inverse proximity effect is relatively
weak. Concomitantly, we find a shift in the critical interface resistance where
the pairing conversion occurs. Our findings suggest a robust and simple method
for producing purely odd-frequency superconducting correlations, that can be
tested experimentally.Comment: 14 pages, 12 figures. Submitted to Physical Review. Chosen as
Editors' Suggestio
Future CMB Constraints on Early, Cold, or Stressed Dark Energy
We investigate future constraints on early dark energy (EDE) achievable by
the Planck and CMBPol experiments, including cosmic microwave background (CMB)
lensing. For the dark energy, we include the possibility of clustering through
a sound speed c_s^2 <1 (cold dark energy) and anisotropic stresses
parameterized with a viscosity parameter c_vis^2. We discuss the degeneracies
between cosmological parameters and EDE parameters. In particular we show that
the presence of anisotropic stresses in EDE models can substantially undermine
the determination of the EDE sound speed parameter c_s^2. The constraints on
EDE primordial energy density are however unaffected. We also calculate the
future CMB constraints on neutrino masses and find that they are weakened by a
factor of 2 when allowing for the presence of EDE, and highly biased if it is
incorrectly ignored.Comment: 12 pages, 19 figure
Informal care provision and work disability days
Due to the demographic change and the concomitant ageing of society, the labor force will reduce in Germany in the following decades. Simultaneously, the demand for informal care will increase as a result of the ageing society. Informal care is assumed being the least expensive form of care and is the most common form of care in Germany. However, the literature conveys the impression that informal care is not easily compatible with a range of situations in life. This is especially confirmed by findings of negative health effects of informal caregiving. Based on these findings, it could be suspected that there have to be large effects on employment, as individuals with health restrictions are supposed to work less. Indeed, findings on effects of informal care provision on employment indicate a rather small or even an insignificant effect. We think that health problems become manifest in some form or another. Thus, the effects of informal care provision on labor supply are possibly larger than it has been assumed so far. To verify our hypothesis, we examine the effects of informal caregiving on a health related labormarket outcome in the form of work disability days using administrative data of Germany's largest sickness fund, the Techniker Krankenkasse with more than 5 million observations. In order to identify the effects of informal care on work disability days, linear regression models are estimated in which is controlled for timeinvariant heterogeneity. The results illustrate a significant positive relationship between informal caregiving and the number of work disability days.Während als eindeutig belegt gilt, dass die informelle Pflege durch Angehörige die in Deutschland am weitesten verbreitete Pflegeform darstellt, besteht in der Literatur kein Konsens über die Auswirkungen der Erbringung derartiger Pflegeleistungen auf die Arbeitsmarktpartizipation und Gesundheit. Die Ergebnisse bereits vorhandener Studien weisen zwar überwiegend auf negative Effekte der Pflege auf die Gesundheit hin, dies spiegelt sich jedoch nicht in einer entsprechenden Verringerung des Arbeitsangebotes wider. Ziel dieser Studie ist es daher zu untersuchen, inwiefern es eine indirekte Verringerung des Arbeitsangebotes gibt, die aus der gesundheitlichen Belastung durch die Pflege resultiert und sich womöglich auf Arbeitsunfähigkeitstage auswirkt. Hierzu werden Routinedaten Deutschlands größter Krankenkasse (der Techniker Krankenkasse) mit über 10 Millionen Versicherten ausgewertet. Die Ergebnisse zeigen große Effekte der informellen Pflegeerbringung auf die Arbeitsunfähigkeitstage, was darauf hinweist, dass die Arbeitsmarkteffekte ohne die Betrachtung der Arbeitsunfähigkeitstage in der bisher existierenden Literatur unterschätzt wurden
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