Search results for "RELATIVITY"
showing 10 items of 1213 documents
Progresses in 3D integral imaging with optical processing
2008
Integral imaging is a promising technique for the acquisition and auto-stereoscopic display of 3D scenes with full parallax and without the need of any additional devices like special glasses. First suggested by Lippmann in the beginning of the 20th century, integral imaging is based in the intersection of ray cones emitted by a collection of 2D elemental images which store the 3D information of the scene. This paper is devoted to the study, from the ray optics point of view, of the optical effects and interaction with the observer of integral imaging systems.
Flat synchronizations in spherically symmetric space-times
2010
It is well known that the Schwarzschild space-time admits a spacelike slicing by flat instants and that the metric is regular at the horizon in the associated adapted coordinates (Painleve-Gullstrand metric form). We consider this type of flat slicings in an arbitrary spherically symmetric space-time. The condition ensuring its existence is analyzed, and then, we prove that, for any spherically symmetric flat slicing, the densities of the Weinberg momenta vanish. Finally, we deduce the Schwarzschild solution in the extended Painleve-Gullstrand-Lemaitre metric form by considering the coordinate decomposition of the vacuum Einstein equations with respect to a flat spacelike slicing.
The Nuremberg Trial in the Finnish Press Discourse
2011
The opening of the Nuremberg Trial was widely reported in Finland, as in other countries examined here. Like the reportage from the liberated concentration camps, the Finnish press was not represented on the spot although it had a quota for one journalist. However, the trial was a much-awaited event in Finland. The Belsen Trial (the trial of Josef Kramer and 44 others), which had ended on 17 November 1945, was duly reported in Finland, and in part indicated that the interest in Nazi criminality was running high.1
Effect of the milling conditions on the degree of amorphization of selenium by milling in a planetary ball mill
2007
The effect of the milling parameters (rotation speed of the milling device and duration of milling) on the phase composition of the products of milling of fully crystalline selenium has been investigated. The milling was conducted using a planetary micromill and the phase composition of the milling products was determined by differential thermal analysis. It has been found that ball milling leads to the partial amorphization of the starting crystalline material. The content of amorphous phase in the milling products depends, in a rather complicated way, on the milling parameters. At the milling parameters adopted in the present study, the milling product was never fully amorphous. The compl…
Toward a scientific and personal biography of Tullio Levi-Civita (1873–1941)
2005
International audience; Tullio Levi-Civita was one of the most important Italian mathematicians in the early part of the 20th century, contributing significantly to a number of research fields in mathematics and physics. In addition, he was involved in the social and political life of his time and suffered severe political and racial persecution during the period of Fascism. He tried repeatedly and in several cases successfully to help colleagues and students who were victims of anti-Semitism in Italy and Germany. His scientific and private life is well documented in the letters and documents contained in his Archive. The authors' aim is to illustrate the events of his life by means of his …
Implicaciones de la evolución histórica de algunos conceptos en la enseñanza de la Relatividad
2006
La relatividad es una parte importante de la fisica moderna. En este articulo se analiza el debate en torno a la utilizacion de la historia de la ciencia para orientar la didactica de la relatividad en la ensenanza secundaria. Se repasa la evolucion historica de algunos conceptos clave de la relatividad especial y se muestra su implicacion en la ensenanza-aprendizaje.Palabras clave: ensenanza-aprendizaje; relatividad; historia de la ciencia.Implications of the historical evolution of some concepts in the teaching of relativityThe relativity is an important part the modern physics. In this article we analyze the discussion around the use of the history of science to guide the didactics of th…
Physics and metaphysics in the Hitchhiker Series (1979-1992) by Douglas Adams
2006
Quantum search of spatial regions
2003
Can Grover's algorithm speed up search of a physical region - for example a 2-D grid of size sqrt(n) by sqrt(n)? The problem is that sqrt(n) time seems to be needed for each query, just to move amplitude across the grid. Here we show that this problem can be surmounted, refuting a claim to the contrary by Benioff. In particular, we show how to search a d-dimensional hypercube in time O(sqrt n) for d at least 3, or O((sqrt n)(log n)^(3/2)) for d=2. More generally, we introduce a model of quantum query complexity on graphs, motivated by fundamental physical limits on information storage, particularly the holographic principle from black hole thermodynamics. Our results in this model include a…
Cavity solitons in nondegenerate optical parametric oscillation
2000
Abstract We find analytically cavity solitons in nondegenerate optical parametric oscillators. These solitons are exact localised solutions of a pair of coupled parametrically driven Ginzburg–Landau equations describing the system for large pump detuning. We predict the existence of a Hopf bifurcation of the soliton resulting in a periodically pulsing localised structure. We give numerical evidence of the analytical results and address the problem of cavity soliton interaction.
Conclusion and Future
2014
After being awarded the EURO 2008, Switzerland faced several challenges related to hosting such a mega sport event. The research has explored how knowledge transfer and the use of certain management tools were important in Switzerland’s organization of fifteen matches and to achieving a happy and prosperous football festival in Switzerland.