993 research outputs found
Redshift and lateshift from homogeneous and isotropic modified dispersion relations
Observables which would indicate a modified vacuum dispersion relations,
possibly caused by quantum gravity effects, are a four momentum dependence of
the cosmological redshift and the existence of a so called lateshift effect for
massless or very light particles. Existence or non-existence of the later is
currently analyzed on the basis of the available observational data from gamma
ray bursts and compared to predictions of specific modified dispersion relation
models. We consider the most general perturbation of the general relativistic
dispersion relation of freely falling particles on homogeneous and isotropic
spacetimes and derive the red- and lateshift to first order in the
perturbation. Our result generalizes the existing formulae in the literature
and we find that there exist modified dispersion relations causing both, one or
none of the two effects to first order.Comment: 9 pages, refs added, extended outlook added, matches published
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Radar orthogonality and radar length in Finsler and metric spacetime geometry
The radar experiment connects the geometry of spacetime with an observers
measurement of spatial length. We investigate the radar experiment on Finsler
spacetimes which leads to a general definition of radar orthogonality and radar
length. The directions radar orthogonal to an observer form the spatial equal
time surface an observer experiences and the radar length is the physical
length the observer associates to spatial objects. We demonstrate these
concepts on a forth order polynomial Finsler spacetime geometry which may
emerge from area metric or pre-metric linear electrodynamics or in quantum
gravity phenomenology. In an explicit generalisation of Minkowski spacetime
geometry we derive the deviation from the euclidean spatial length measure in
an observers rest frame explicitly.Comment: 18 pages, 7 figures, axes label in figures corrected, journal
references adde
The Heterogeneous Economic Consequences of Works Council Relations
I use a question about works council relations from the 2006 wave of the IAB Establishment panel to analyze the heterogeneous effects of works councils on productivity, wages, and profits. The results indicate that the effects differ significantly between works council relationship types in a systematic pattern. The overall findings are in line with productivity-enhancing and rent-sharing functions of works councils.industrial relations, firm performance, codetermination, works councils
A Note on Risk Aversion and Labour Market Outcomes: Further Evidence from German Survey Data
Using the large-scale German Socio-Economic Panel, this note reports direct empirical evidence for significant correlations between risk aversion and labour market outcomes (full-time employment, temporary agency work, fixed-term contracts, employer change, quits, training, wages, and job satisfaction).employment, job search, human capital, risk aversion, wages
Effective Working Hours and Wages: The Case of Downward Adjustment via Paid Absenteeism
This paper compares contractual with effective working hours and wages, respectively. Effective working hours are defined as contractual working hours minus absent working hours. This approach takes into account workers' downward adjustment of working time via paid absenteeism if working time constraints are present, which induce workers to accept contracts with larger than their optimal choice of working hours. A German personnel data set, which contains precise information on wages as well as working and absence hours, is used to assess the impact of such downward adjustment on wage inequality and wage differentials (gender, schooling, age).absenteeism, earnings, inequality, wage differentials, working hours
The Heterogeneous Economic Consequences of Works Council Relations
I use a question about works council relations from the 2006 wave of the IAB Establishment panel to analyze the heterogeneous effects of works councils on productivity, wages, and profits. The results indicate that the effects differ significantly between works council relationship types in a systematic pattern. The overall findings are in line with productivity-enhancing and rent-sharing functions of works councils.Codetermination; Firm performance; Industrial relations; Works councils
Risk Aversion and Sorting into Public Sector Employment
This research note uses two German data sets â the large-scale German Socio-Economic Panel and unique data from own student questionnaires â to analyse the relationship between risk aversion and the choice for public sector employment. Main results are: (1) more risk averse individuals sort into public sector employment, (2) the impact of career specific and unemployment risk attitudes is larger than the impact of general risk attitudes, and (3) risk taking is rewarded with higher wages in the private but not in the public sector.public sector, risk aversion, sorting, wage differentials
Electromagnetic Potential in Pre-Metric Electrodynamics: Causal Structure, Propagators and Quantization
An axiomatic approach to electrodynamics reveals that Maxwell electrodynamics
is just one instance of a variety of theories for which the name
electrodynamics is justified. They all have in common that their fundamental
input are Maxwell's equations (or ) and
and a constitutive law H = # F which relates the field
strength two-form and the excitation two-form . A local and linear
constitutive law defines what is called local and linear pre-metric
electrodynamics whose best known application are the effective description of
electrodynamics inside media including, e.g., birefringence. We analyze the
classical theory of the electromagnetic potential before we use methods
familiar from mathematical quantum field theory in curved spacetimes to
quantize it in a locally covariant way. Our analysis of the classical theory
contains the derivation of retarded and advanced propagators, the analysis of
the causal structure on the basis of the constitutive law (instead of a metric)
and a discussion of the classical phase space. This classical analysis sets the
stage for the construction of the quantum field algebra and quantum states.
Here one sees, among other things, that a microlocal spectrum condition can be
formulated in this more general setting.Comment: 34 pages, references added, update to published version, title
updated to published versio
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