158 research outputs found
On the Axiomatics of the 5-dimensional Projective Unified Field Theory of Schmutzer
For more than 40 years E.Schmutzer has developed a new approach to the
(5-dimensional) projective relativistic theory which he later called Projective
Unified Field Theory (PUFT). In the present paper we introduce a new axiomatics
for Schmutzer's theory. By means of this axiomatics we can give a new
geometrical interpretation of the physical concept of the PUFT.Comment: 32 pages, 1 figure, LaTeX 2e, will be submitted to Genaral Relativity
and Gravitatio
Gravitational Couplings of Intrinsic Spin
The gravitational couplings of intrinsic spin are briefly reviewed. A
consequence of the Dirac equation in the exterior gravitational field of a
rotating mass is considered in detail, namely, the difference in the energy of
a spin-1/2 particle polarized vertically up and down near the surface of a
rotating body is . Here is the latitude and
, where and are, respectively, the angular
momentum and radius of the body. It seems that this relativistic quantum
gravitational effect could be measurable in the foreseeable future.Comment: LaTeX file, no figures, 16 page
Fibre bundle formulation of relativistic quantum mechanics. I. Time-dependent approach
We propose a new fibre bundle formulation of the mathematical base of
relativistic quantum mechanics. At the present stage the bundle form of the
theory is equivalent to its conventional one, but it admits new types of
generalizations in different directions.
In the present first part of our investigation we consider the time-dependent
or Hamiltonian approach to bundle description of relativistic quantum
mechanics. In it the wavefunctions are replaced by (state) liftings of paths or
sections along paths of a suitably chosen vector bundle over space-time whose
(standard) fibre is the space of the wavefunctions. Now the quantum evolution
is described as a linear transportation (by means of the evolution transport
along paths in the space-time) of the state liftings/sections in the (total)
bundle space. The equations of these transportations turn to be the bundle
versions of the corresponding relativistic wave equations.Comment: 16 standard LaTeX pages. The packages AMS-LaTeX and amsfonts are
required. The paper continuous the application of fibre bundle formalism to
quantum physics began in the series of works quant-ph/9803083,
quant-ph/9803084, quant-ph/9804062, quant-ph/9806046, quant-ph/9901039,
quant-ph/9902068, and quant-ph/0004041. For related papers, view
http://theo.inrne.bas.bg/~bozho
Flows and particles with shear-free and expansion-free velocities in (L^-_n,g)- and Weyl's spaces
Conditions for the existence of flows with non-null shear-free and
expansion-free velocities in spaces with affine connections and metrics are
found. On their basis, generalized Weyl's spaces with shear-free and
expansion-free conformal Killing vectors as velocity's vectors of spinless test
particles moving in a Weyl's space are considered. The necessary and sufficient
conditions are found under which a free spinless test particle could move in
spaces with affine connections and metrics on a curve described by means of an
auto-parallel equation. In Weyl's spaces with Weyl's covector, constructed by
the use of a dilaton field, the dilaton field appears as a scaling factor for
the rest mass density of the test particle. PACS numbers: 02.40.Ky, 04.20.Cv,
04.50.+h, 04.90.+eComment: 20 pages, LaTeX, to appear in Classical and Quantum Gravity. arXiv
admin note: substantial text overlap with arXiv:gr-qc/001104
Frames of reference in spaces with affine connections and metrics
A generalized definition of a frame of reference in spaces with affine
connections and metrics is proposed based on the set of the following
differential-geometric objects:
(a) a non-null (non-isotropic) vector field,
(b) the orthogonal to the vector field sub space,
(c) an affine connection and the related to it covariant differential
operator determining a transport along the given non-null vector filed.
On the grounds of this definition other definitions related to the notions of
accelerated, inertial, proper accelerated and proper inertial frames of
reference are introduced and applied to some mathematical models for the
space-time. The auto-parallel equation is obtained as an Euler-Lagrange's
equation. Einstein's theory of gravitation appears as a theory for
determination of a special frame of reference (with the gravitational force as
inertial force) by means of the metrics and the characteristics of a material
distribution.
PACS numbers: 0490, 0450, 1210G, 0240VComment: 17 pages, LaTeX 2
Domains of disgust sensitivity: revisited factor structure of the questionnaire for the assessment of disgust sensitivity (QADS) in a cross-sectional, representative german survey
<p>Abstract</p> <p>Background</p> <p>Disgust sensitivity is defined as a predisposition to experiencing disgust, which can be measured on the basis of the Disgust Scale and its German version, the Questionnaire for the Assessment of Disgust Sensitivity (QADS). In various studies, different factor structures were reported for either instrument. The differences may most likely be due to the selected factor analysis estimation methods and the small non-representative samples. Consequently, the aims of this study were to explore and confirm a theory-driven and statistically coherent QADS factor structure in a large representative sample and to present its standard values.</p> <p>Methods</p> <p>The QADS was answered by N = 2473 healthy subjects. The respective households and participants were selected using the random-route sampling method. Afterwards, the collected sample was compared to the information from the Federal Statistical Office to ensure that it was representative for the German residential population. With these data, an exploratory Promax-rotated Principal Axis Factor Analysis as well as comparative confirmatory factor analyses with robust Maximum Likelihood estimations were computed. Any possible socio-demographic influences were quantified as effect sizes.</p> <p>Results</p> <p>The data-driven and theoretically sound solution with the three highly interrelated factors Animal Reminder Disgust, Core Disgust, and Contamination Disgust led to a moderate model fit. All QADS scales had very good reliabilities (Cronbach's alpha) from .90 to .95. There were no age-differences found among the participants, however, the female participants showed remarkably higher disgust ratings.</p> <p>Conclusions</p> <p>Based on the representative sample, the QADS factor structure was revised. Gender-specific standard percentages permit a population-based assessment of individual disgust sensitivity. The differences of the original QADS, the new solution, and the Disgust Scale - Revised will be discussed.</p
Sequencing of BAC pools by different next generation sequencing platforms and strategies
<p>Abstract</p> <p>Background</p> <p>Next generation sequencing of BACs is a viable option for deciphering the sequence of even large and highly repetitive genomes. In order to optimize this strategy, we examined the influence of read length on the quality of Roche/454 sequence assemblies, to what extent Illumina/Solexa mate pairs (MPs) improve the assemblies by scaffolding and whether barcoding of BACs is dispensable.</p> <p>Results</p> <p>Sequencing four BACs with both FLX and Titanium technologies revealed similar sequencing accuracy, but showed that the longer Titanium reads produce considerably less misassemblies and gaps. The 454 assemblies of 96 barcoded BACs were improved by scaffolding 79% of the total contig length with MPs from a non-barcoded library.</p> <p>Assembly of the unmasked 454 sequences without separation by barcodes revealed chimeric contig formation to be a major problem, encompassing 47% of the total contig length. Masking the sequences reduced this fraction to 24%.</p> <p>Conclusion</p> <p>Optimal BAC pool sequencing should be based on the longest available reads, with barcoding essential for a comprehensive assessment of both repetitive and non-repetitive sequence information. When interest is restricted to non-repetitive regions and repeats are masked prior to assembly, barcoding is non-essential. In any case, the assemblies can be improved considerably by scaffolding with non-barcoded BAC pool MPs.</p
First light of VLT/HiRISE: High-resolution spectroscopy of young giant exoplanets
A major endeavor of this decade is the direct characterization of young giant
exoplanets at high spectral resolution to determine the composition of their
atmosphere and infer their formation processes and evolution. Such a goal
represents a major challenge owing to their small angular separation and
luminosity contrast with respect to their parent stars. Instead of designing
and implementing completely new facilities, it has been proposed to leverage
the capabilities of existing instruments that offer either high contrast
imaging or high dispersion spectroscopy, by coupling them using optical fibers.
In this work we present the implementation and first on-sky results of the
HiRISE instrument at the very large telescope (VLT), which combines the
exoplanet imager SPHERE with the recently upgraded high resolution spectrograph
CRIRES using single-mode fibers. The goal of HiRISE is to enable the
characterization of known companions in the band, at a spectral resolution
of the order of , in a few hours of
observing time. We present the main design choices and the technical
implementation of the system, which is constituted of three major parts: the
fiber injection module inside of SPHERE, the fiber bundle around the telescope,
and the fiber extraction module at the entrance of CRIRES. We also detail the
specific calibrations required for HiRISE and the operations of the instrument
for science observations. Finally, we detail the performance of the system in
terms of astrometry, temporal stability, optical aberrations, and transmission,
for which we report a peak value of 3.9% based on sky measurements in
median observing conditions. Finally, we report on the first astrophysical
detection of HiRISE to illustrate its potential.Comment: 17 pages, 15 figures, 3 tables. Submitted to A&A on 19 September 202
First light of VLT/HiRISE: High-resolution spectroscopy of young giant exoplanets
A major endeavor of this decade is the direct characterization of young giant exoplanets at high spectral resolution to determine the composition of their atmosphere and infer their formation processes and evolution. Such a goal represents a major challenge owing to their small angular separation and luminosity contrast with respect to their parent stars. Instead of designing and implementing completely new facilities, it has been proposed to leverage the capabilities of existing instruments that offer either high-contrast imaging or high-dispersion spectroscopy by coupling them using optical fibers. In this work, we present the implementation and first on-sky results of the High-Resolution Imaging and Spectroscopy of Exoplanets (HiRISE) instrument at the Very Large Telescope (VLT), which combines the exoplanet imager SPHERE with the recently upgraded high-resolution spectrograph CRIRES using single-mode fibers. The goal of HiRISE is to enable the characterization of known companions in the H band at a spectral resolution on the order of R = λ/∆λ = 100 000 in a few hours of observing time. We present the main design choices and the technical implementation of the system, which is constituted of three major parts: the fiber injection module inside of SPHERE, the fiber bundle around the telescope, and the fiber extraction module at the entrance of CRIRES. We also detail the specific calibrations required for HiRISE and the operations of the instrument for science observations. Finally, we detail the performance of the system in terms of astrometry, temporal stability, optical aberrations, and transmission, for which we report a peak value of ~3.9% based on sky measurements in median observing conditions. Finally, we report on the first astrophysical detection of HiRISE to illustrate its potential
From Clock Synchronization to Dark Matter as a Relativistic Inertial Effect
Lecture at BOSS2011 on relativistic metrology, on clock synchronization,
relativistic dynamics and non-inertial frames in Minkowski spacetime, on
relativistic atomic physics, on ADM canonical tetrad gravity in asymptotically
Minkowskian spacetimes, on the York canonical basis identifying the inertial
(gauge) and tidal degrees of freedom of the gravitational field, on the
Post-Minkowskian linearization in 3-orthogonal gauges, on the Post-Newtonian
limit of matter Hamilton equations, on the possibility to interpret dark matter
as a relativistic inertial effect connected with relativistic metrology (i.e.
clock synchronization) in Einstein GR.Comment: 90 pages. Lecture at BOSS201
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