Einstein time dilatation

Equation (2.13.8) is called the Lorentz-FitzGerald94 contraction of space Eq. (2.13.11) is the Einstein time dilatation A clock advances more slowly in a system moving at a high speed V. When V Lorentz transformation reduces to the Galilean transformation. 

For a polemic against the common but convenient practice of referring to relativistic mass versus rest mass see Okun L (1989) Phys Today June 1989 30. Relativistic effects like mass increase and time decrease (time dilation) at a velocity v are given by what we may call the Einstein factor , V(l-v2/c2), where c is the velocity of light. The inner electrons of a heavy atom can move at about 0.3c, so here the mass increase is l/V(l-v2/c2) = l/V(l-0.32) = 1/ 0.95 = 1.05 or 5 percent. Small but significant... 

The massive volume of hot air, by way of a century s worth of comment on aether drift and time dilation, is totally irrelevant to the central issue. Even typographical errors in Einstein s papers have been quoted as evidence against the validity of of the theory of relativity. 

This effect is known as time dilation. Of course, for the passengers waiting at the tram stop and watching the eloek, its two ticks would be separated by exactly 1 second. If Einstein took his watch out of his waistcoat pocket and showed it to them through the window, they would be amazed. The seconds will pass at the tram stop, while Einstein s watch would seem to have stopped. This effect has been double-checked experimentally many times. For example, the meson lives such a short time (in the coordinate system associated with it), that when created by cosmic rays in the stratosphere, it would have no chance of reaching a surface laboratory before decaying. Nevertheless, as seen from the laboratory coordinate system, the meson s clock ticks very slowly and mesons are observable. 

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