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Stoa und Stoiker: 2 Bände. Griechisch - Lateinisch - Deutsch. Nietzsche, Versuch einer Mythologie. Gottsched, Johann Christoph, Theoretische Schriften, Versuch einer critischen Dichtkunst, Horaz von der Dichtkunst, Horaz von der Dichtkunst.

Books The Project Gutenberg EBook of The Notebooks of Leonardo Da Vinci, Complete by Leonardo Da Vinci (#3 in our series by Leonardo Da Vinci) Copyright laws are changing all over the world.

Be sure to check the copyright laws for your country before downloading or redistributing this or any other Project Gutenberg eBook. This header should be the first thing seen when viewing this Project Gutenberg file. Please do not remove it. Do not change or edit the header without written permission. Rhetorik übersetzt und erlaeutert - Aristotle. Im Buch blättern: Fontane, Theodor: Irrungen, Wirrungen. Roman. 100 Ideas. Tests of general relativity. The very strong gravitational fields that must be present close to black holes, especially those supermassive black holes which are thought to power active galactic nuclei and the more active quasars, belong to a field of intense active research.

Tests of general relativity

Graviton. Theory[edit] The three other known forces of nature are mediated by elementary particles: electromagnetism by the photon, the strong interaction by the gluons, and the weak interaction by the W and Z bosons.


The hypothesis is that the gravitational interaction is likewise mediated by an – as yet undiscovered – elementary particle, dubbed as the graviton. In the classical limit, the theory would reduce to general relativity and conform to Newton's law of gravitation in the weak-field limit.[6][7][8] Gravitons and renormalization[edit] When describing graviton interactions, the classical theory (i.e., the tree diagrams) and semiclassical corrections (one-loop diagrams) behave normally, but Feynman diagrams with two (or more) loops lead to ultraviolet divergences; that is, infinite results that cannot be removed because the quantized general relativity is not renormalizable, unlike quantum electrodynamics.

Comparison with other forces[edit] Fundamental interaction. Fundamental interactions, also called fundamental forces or interactive forces, are modeled in fundamental physics as patterns of relations in physical systems, evolving over time, that appear not reducible to relations among entities more basic.

Fundamental interaction

Four fundamental interactions are conventionally recognized: gravitational, electromagnetic, strong nuclear, and weak nuclear. Everyday phenomena of human experience are mediated via gravitation and electromagnetism. The strong interaction, synthesizing chemical elements via nuclear fusion within stars, holds together the atom's nucleus, and is released during an atomic bomb's detonation. Gravity Probe B - Special & General Relativity Questions and Answers. It is true that, given enough energy, you could be propelled so fast that 1 year back home would pass for you in a few minutes; a ride across the Milky Way covering 100,000 light years could be done in a few seconds; or even a ride across the visible universe of 14 billion light years could be done in a second or less...given an ultimate source of power to get you to those speeds.

Gravity Probe B - Special & General Relativity Questions and Answers

For a photon, or any other particle traveling at ESSENTIALLY the speed of light, any arbitrarily long distance could be traversed in less than a second....but eternity is different. For you to get boosted to a speed where 'eternity would pass in an instant' you would travel essentially an infinite distance, and the energy you would need to accelerate you would be infinite as well. Vis-viva equation. Einführung in die Theoretische Physik - Ein Lehrbuch in mehreren Bänden – Wikibooks, Sammlung freier Lehr-, Sach- und Fachbücher. Mathematik: Inhaltsübersicht – Wikibooks, Sammlung freier Lehr-, Sach- und Fachbücher. Quantum electrodynamics.

In particle physics, quantum electrodynamics (QED) is the relativistic quantum field theory of electrodynamics.

Quantum electrodynamics

In essence, it describes how light and matter interact and is the first theory where full agreement between quantum mechanics and special relativity is achieved. QED mathematically describes all phenomena involving electrically charged particles interacting by means of exchange of photons and represents the quantum counterpart of classical electromagnetism giving a complete account of matter and light interaction.

History[edit] Vector. From Wikipedia, the free encyclopedia Vector may refer to: In mathematics and physics[edit] In computer science[edit] In biology[edit]


Tensor. Cauchy stress tensor, a second-order tensor.


The tensor's components, in a three-dimensional Cartesian coordinate system, form the matrix whose columns are the stresses (forces per unit area) acting on the e1, e2, and e3 faces of the cube. Tensors are used to represent correspondences between sets of geometric vectors. For example, the Cauchy stress tensor T takes a direction v as input and produces the stress T(v) on the surface normal to this vector for output thus expressing a relationship between these two vectors, shown in the figure (right). Because they express a relationship between vectors, tensors themselves must be independent of a particular choice of coordinate system. Tensors are important in physics because they provide a concise mathematical framework for formulating and solving physics problems in areas such as elasticity, fluid mechanics, and general relativity.

Definition[edit] There are several approaches to defining tensors. Electric field. Electric field lines emanating from a point positive electric charge suspended over an infinite sheet of conducting material.

Electric field

Qualitative description[edit] An electric field that changes with time, such as due to the motion of charged particles producing the field, influences the local magnetic field. Allgemeinbildung. Dimensional analysis. Dimensional analysis is routinely used as a check on the plausibility of derived equations and computations.

Dimensional analysis

It is also used to categorize types of physical quantities and units based on their relationship to or dependence on other units. Great principle of similitude[edit] The basic principle of dimensional analysis was known to Isaac Newton (1686) who referred to it as the "Great Principle of Similitude".[1] James Clerk Maxwell played a major role in establishing modern use of dimensional analysis by distinguishing mass, length, and time as fundamental units, while referring to other units as derived.[2] The 19th-century French mathematician Joseph Fourier made important contributions[3] based on the idea that physical laws like F = ma should be independent of the units employed to measure the physical variables.

Definition[edit] The term dimension is more abstract than scale unit: mass is a dimension, while kilograms are a scale unit (choice of standard) in the mass dimension. Tests of special relativity. Special relativity is a physical theory that plays a fundamental role in the description of all physical phenomena, as long as gravitation is not significant. Many experiments played (and still play) an important role in its development and justification. The strength of the theory lies in its unique ability to correctly predict to high precision the outcome of an extremely diverse range of experiments. Light-time correction. Light-time correction is a displacement in the apparent position of a celestial object from its true position (or geometric position) caused by the object's motion during the time it takes its light to reach an observer.