10 research outputs found
Gedankenexperimente ĂŒber Quantenmechanik und Gravitation
In dieser Arbeit sollen Gedankenexperimente ĂŒber Quantenmechanik und Gravitation formuliert und analysiert werden. Wir wollen untersuchen welche Möglichkeiten im Rahmen eines Gedankenexperimentes bestehen mehr ĂŒber die Beziehung von Quantenmechanik und Gravitation zu lernen. Diese Gedankenexperimente sollen auch auf Ihre Realisierbarkeit untersucht werden. In einem ersten Gedankenexperiment wird einer Ăberlegung Werner Heisenbergs zur Suche nach UnschĂ€rferelationen gefolgt und diese auf die Gravitation angewendet. Dabei wird ein Weg gezeigt UnschĂ€rferelationen fĂŒr linearisierte Gravitationsfelder (gravitoelektromagnetische Felder) zu finden. In einem zweiten Gedankenexperiment wird die DekohĂ€renz bei Interferenzexperimenten durch gravitative Wechselwirkung untersucht und welche Auswirkungen dies fĂŒr verschiedene Modelle des spontanen Wellenkollapses hat. Es werden zwei Gedankenexperimente mit Mach-Zehnder Interferometern formuliert, die eine Unterscheidung zwischen Alternativmodellen und der Quantenmechanik ermöglichen. Wie gezeigt wird, sind diese Experimente mit dem momentanen Stand der Experimental-Technik nicht zu realisieren und dienen der Anschauung
Against the ânightmare of a mechanically determined universeâ: Why Bohm was never a Bohmian
David Bohm has put forward the first deterministic interpretation of quantum physics, and
for this he seems to be regarded as a champion of determinism by physicists (both his contemporaries and the supporters of his interpretation, the so-called âBohmiansâ) as well
as by historians of physics. The standard narrative is that he underwent a âconversionâ from being a supporter of Bohr to being a staunch determinist, due to his interaction with
Einstein and his commitment to Marxism. Here we show that Bohm actually upheld with continuity throughout his career some philosophical tenets that included a strong rejection
of mechanistic determinism. As such, we conclude that Bohm was never a Bohmian and that his philosophical views have been largely misinterpreted
Heisenberg's Uncertainty Relation and Bell Inequalities in High Energy Physics
An effective formalism is developed to handle decaying two-state systems.
Herewith, observables of such systems can be described by a single operator in
the Heisenberg picture. This allows for using the usual framework in quantum
information theory and, hence, to enlighten the quantum feature of such systems
compared to non-decaying systems. We apply it to systems in high energy
physics, i.e. to oscillating meson-antimeson systems. In particular, we discuss
the entropic Heisenberg uncertainty relation for observables measured at
different times at accelerator facilities including the effect of CP violation,
i.e. the imbalance of matter and antimatter. An operator-form of Bell
inequalities for systems in high energy physics is presented, i.e. a
Bell-witness operator, which allows for simple analysis of unstable systems.Comment: 17 page
Notions of Completeness in the EPR Discussion
We explore the different notions of completeness applied in the EPR discussion following and amending the thorough analysis of Arthur Fine. To this aim, we propose a classification scheme for scientific theories that provides a methodology for analyzing the different levels at which interpretive approaches come into play. This allows us to contrast several concepts of completeness that operate on specific levels of the theory. We introduce the notion of theory completeness and compare it with the established notions of Born completeness, Schrödinger completeness and bijective completeness. We relate these notions to the recent concept of Ï-completeness and predictable completeness. The paper shows that the EPR argument contains conflicting versions of completeness. The confusion of these notions led to misunderstandings in the EPR debate and hindered its progress. Their clarification will thus contribute to recent debates on interpretational issues of quantum mechanics. Finally, we discuss the connection between the EPR paper and the EinsteinâRosen paper with regard to the question of completeness
Inanspruchnahme, EffektivitĂ€t und inhaltliche Relevanz der Mathematik-BrĂŒckenkurse an der Fachhochschule Technikum Wien
Empirical Analysis of Safe Distance Calculation by the Stereoscopic Capturing and Processing of Images Through the Tailigator System
Driver disregard for the minimum safety distance increases the probability of rear-end collisions. In order to contribute to active safety on the road, we propose in this work a low-cost Forward Collision Warning system that captures and processes images. Using cameras located in the rear section of a leading vehicle, this system serves the purpose of discouraging tailgating behavior from the vehicle driving behind. We perform in this paper the pertinent field tests to assess system performance, focusing on the calculated distance from the processing of images and the error margins in a straight line, as well as in a curve. Based on the evaluation results, the current version of the Tailigator can be used at speeds up to 50 km per hour without any restrictions. The measurements showed similar characteristics both on the straight line and in the curve. At close distances, between 3 and 5 m, the values deviated from the real value. At average distances, around 10 to 15 m, the Tailigator achieved the best results. From distances higher than 20 m, the deviations increased steadily with the distance. We contribute to the state of the art with an innovative low-cost system to identify tailgating behavior and raise awareness, which works independently of the rear vehicle’s communication capabilities or equipment
Empirical Analysis of Safe Distance Calculation by the Stereoscopic Capturing and Processing of Images Through the Tailigator System
Educational activities with photonics explorer
In this paper we present various educational activities with Photonics Explorer, an educational kit developed by the photonics research team B - PHOT at VUB (Vrije Universiteit Brussel) for students at secondary schools. The concept is a âlab-in-a-boxâ that enables students of the 2 nd and 3 rd grade to do photonics experiments themselves at school with lasers, LEDs, lenses, optical fibers, and other high-tech components. Even though, the kit was developed for the secondary schools, we use experiments from the kit also for some other teaching activities such as lectures at the university, photonics workshops for teachers and children at primary/secondary schools or for events such as children's/youth's university or the night of sciences. In the frame of Austrian based project Phorsch! we have organized most of these activities which will be presented here