36,227 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
versio
Mechanisms of conflict and dispute resolution in Ancient Near Eastern Treaties
The paper focuses on the problems of a juridical classification and evaluation of Ancient Near Eastern treaties with regard to the question if there existed an Ancient Near Eastern International Law or not. Alternatively treaties and their content are looked at uncommitted as mechanisms of conflict and dispute resolution. Main aspects are preliminary and prophylactic conflict resolution in treaties and the procedural context and efficiency of treaties
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
Naïve Panentheism
Karl Pfeifer attempts to present a coherent view of panentheism that eschews Pickwickian senses of “in” and aligns itself with, and builds upon, familiar diagrammed portrayals of panentheism. The account is accordingly spatial-locative and moreover accepts the proposal of R.T. Mullins that absolute space and time be regarded as attributes of God. In addition, however, it argues that a substantive parthood relation between the world and God is required. Pfeifer’s preferred version of panpsychism, viz. panintentionalism, is thrown into the mix as an optional add-on. On this account, God is conceived of as a “spiritual field” whose nature can be made more intelligible by regarding “God” as having a mass-noun sense in some contexts. Pfeifer closes with the suggestion that we look to topology and mereology for further development of the position outlined in his paper
Observers' measurements in premetric electrodynamics I: Time and radar length
The description of an observer's measurement in general relativity and the
standard model of particle physics is closely related to the spacetime metric.
In order to understand and interpret measurements, which test the metric
structure of the spacetime, like the classical Michelson-Morley, Ives-Stilwell,
Kennedy-Thorndike experiments or frequency comparison experiments in general,
it is necessary to describe them in theories, which go beyond the Lorentzian
metric structure. However, this requires a description of an observer's
measurement without relying on a metric. We provide such a description of an
observer's measurement of the fundamental quantities time and length derived
from a premetric perturbation of Maxwell's electrodynamics and a discussion on
how these measurements influence classical relativistic observables like time
dilation and length contraction. Most importantly, we find that the
modification of electrodynamics influences the measurements at two instances:
the propagation of light is altered as well as the observer's proper time
normalization. When interpreting the results of a specific experiment, both
effects cannot be disentangled, in general, and have to be taken into account.Comment: 18 pages, updated to journal version, typos corrected, discussion
extende
Generating VaR scenarios with product beta distributions
We propose a Monte Carlo simulation method to generate stress tests by VaR
scenarios under Solvency II for dependent risks on the basis of observed data.
This is of particular interest for the construction of Internal Models and
requirements on evaluation processes formulated in the Commission Delegated
Regulation. The approach is based on former work on partition-ofunity copulas,
however with a direct scenario estimation of the joint density by product beta
distributions after a suitable transformation of the original data.Comment: 10 pages, 25 figures, 5 table
Risk Aversion and Sorting into Public Sector Employment
This research note uses two German data sets – the large-scale German Socio-Economic Panel and unique data from own student questionnaires – 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
Incrementally Learned Mixture Models for GNSS Localization
GNSS localization is an important part of today's autonomous systems,
although it suffers from non-Gaussian errors caused by non-line-of-sight
effects. Recent methods are able to mitigate these effects by including the
corresponding distributions in the sensor fusion algorithm. However, these
approaches require prior knowledge about the sensor's distribution, which is
often not available. We introduce a novel sensor fusion algorithm based on
variational Bayesian inference, that is able to approximate the true
distribution with a Gaussian mixture model and to learn its parametrization
online. The proposed Incremental Variational Mixture algorithm automatically
adapts the number of mixture components to the complexity of the measurement's
error distribution. We compare the proposed algorithm against current
state-of-the-art approaches using a collection of open access real world
datasets and demonstrate its superior localization accuracy.Comment: 8 pages, 5 figures, published in proceedings of IEEE Intelligent
Vehicles Symposium (IV) 201
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