Lorentz contraction, Bell's spaceships and rigid body motion in special relativity

RNG Rigid Body Motion

This note outlines how the coupling between the motion of rigid bodies immersed in a fluid and the motion of this fluid is handled in XNS. For a rigid body one has a group of nodes which define the surface of the rigid body called “reference node group” (RNG). For each RNG we save the properties of motion in arrays which in the following we will call “RNG arrays”. They contain the bottom and to...

Non-Rigid Body Motion

During the last few years motion analysis has developed into a major field of interest in image analysis and understanding . Considerable progress has been made as evidenced by the number of publications . However , most of these have been confined to the study of rigid body mot ion . Very few have addressed the issue of non-rigid body motion which poses many interesting and difficult problems ...

Extending Special Relativity to Superluminal Motion

Experiments done with single photon in the early 1990’s produced a surprising result: that single photon pass through a photon tunnel barrier with a group velocity faster than the vacuum speed of light. Recently, a series of experiments revealed that electromagnetic wave was able to travel at a group velocity faster than c. These phenomena have been observed in dispersive media. We think all pa...

The Lagrange rigid body motion

Uniformly moving clocks in special relativity : Time dilatation , but no relativity of simultaneity or length contraction

Time-like and space-like invariant space-time intervals are used to analyse measurements of spatial and temporal distances defined by two spatially-separated clocks. The time dilatation effect is confirmed, but not 'relativity of simultaneity' or 'relativistic length contraction'. How these latter, spurious, effects arise from misuse of the Lorentz transformation is also explained. PACS 03.30.+...