@article{SchmidtBechmann2014,
  author    = {Schmidt, Joachim and Bechmann, Wolfgang},
  title     = {Zur Anwendung des Skalarprodukts von Kraft und Weg auf reversible Prozesse (Druck-Volumen-{\"A}nderung, Dehnung, Elektrostatische Wechselwirkung, Hub)},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-69732},
  year      = {2014},
  abstract  = {Wir schlagen einen allgemein anwendbaren Algorithmus vor, der unter Verwendung des Skalarprodukts von Kraft und Weg zum richtigen Vorzeichen in den Gleichungen f{\"u}r die Arbeit und die Potentielle Energie bei reversiblen Prozessen (Druck-Volumen-{\"A}nderung, Dehnung, Elektrostatische Wechselwirkung, Hub)f{\"u}hrt. Wir zeigen, dass es dabei m{\"o}glich ist, systemimmanente oder externe Kr{\"a}fte zu benutzen. Wir zeigen, dass bei Verwendung von systemimmanenten Kr{\"a}ften das Skalarprodukt mit negativem Vorzeichen anzusetzen ist. Zudem ist es sehr wichtig, n{\"o}tige Vorzeichenwechsel bei den einzelnen Schritten zu beachten. Wir betonen dies, weil gelegentlich {\"u}bersehen wird, dass ein Vorzeichenwechsel n{\"o}tig ist, wenn das Wegdifferential ds durch das H{\"o}hendifferential dh beziehungsweise durch das Abstandsdifferential dx oder dr ersetzt werden muss.},
  language  = {de}
}
@phdthesis{Oancea2021,
  author    = {Oancea, Marius-Adrian},
  title     = {Spin Hall effects in general relativity},
  doi       = {10.25932/publishup-50229},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-502293},
  school      = {Universit{\"a}t Potsdam},
  pages     = {vii, 123},
  year      = {2021},
  abstract  = {The propagation of test fields, such as electromagnetic, Dirac or linearized gravity, on a fixed spacetime manifold is often studied by using the geometrical optics approximation. In the limit of infinitely high frequencies, the geometrical optics approximation provides a conceptual transition between the test field and an effective point-particle description. The corresponding point-particles, or wave rays, coincide with the geodesics of the underlying spacetime. For most astrophysical applications of interest, such as the observation of celestial bodies, gravitational lensing, or the observation of cosmic rays, the geometrical optics approximation and the effective point-particle description represent a satisfactory theoretical model. However, the geometrical optics approximation gradually breaks down as test fields of finite frequency are considered. In this thesis, we consider the propagation of test fields on spacetime, beyond the leading-order geometrical optics approximation. By performing a covariant Wentzel-Kramers-Brillouin analysis for test fields, we show how higher-order corrections to the geometrical optics approximation can be considered. The higher-order corrections are related to the dynamics of the spin internal degree of freedom of the considered test field. We obtain an effective point-particle description, which contains spin-dependent corrections to the geodesic motion obtained using geometrical optics. This represents a covariant generalization of the well-known spin Hall effect, usually encountered in condensed matter physics and in optics. Our analysis is applied to electromagnetic and massive Dirac test fields, but it can easily be extended to other fields, such as linearized gravity. In the electromagnetic case, we present several examples where the gravitational spin Hall effect of light plays an important role. These include the propagation of polarized light rays on black hole spacetimes and cosmological spacetimes, as well as polarization-dependent effects on the shape of black hole shadows. Furthermore, we show that our effective point-particle equations for polarized light rays reproduce well-known results, such as the spin Hall effect of light in an inhomogeneous medium, and the relativistic Hall effect of polarized electromagnetic wave packets encountered in Minkowski spacetime.},
  language  = {en}
}
@phdthesis{Kubas2005,
  author    = {Kubas, Daniel},
  title     = {Applications of Galactic Microlensing},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-5179},
  school      = {Universit{\"a}t Potsdam},
  year      = {2005},
  abstract  = {Subject of this work is the study of applications of the Galactic Microlensing effect, where the light of a distant star (source) is bend according to Einstein's theory of gravity by the gravitational field of intervening compact mass objects (lenses), creating multiple (however not resolvable) images of the source. Relative motion of source, observer and lens leads to a variation of deflection/magnification and thus to a time dependant observable brightness change (lightcurve), a so-called microlensing event, lasting weeks to months. The focus lies on the modeling of binary-lens events, which provide a unique tool to fully characterize the lens-source system and to detect extra-solar planets around the lens star. Making use of the ability of genetic algorithms to efficiently explore large and intricate parameter spaces in the quest for the global best solution, a modeling software (Tango) for binary lenses is developed, presented and applied to data sets from the PLANET microlensing campaign. For the event OGLE-2002-BLG-069 the 2nd ever lens mass measurement has been achieved, leading to a scenario, where a G5III Bulge giant at 9.4 kpc is lensed by an M-dwarf binary with total mass of M=0.51 solar masses at distance 2.9 kpc. Furthermore a method is presented to use the absence of planetary lightcurve signatures to constrain the abundance of extra-solar planets.},
  subject      = {Planeten},
  language  = {en}
}