国際リニアコライダー
For example, a 45 GeV electron accelerated by the Large Electron–Positron Collider (LEP) at Cern in 1989 would have had a Lorentz factor γ of about 88,000 (45 GeV divided by the electron rest mass of 511 keV). Its coordinate speed "v" would have been about sixty four trillionths shy of lightspeed "c" at 1 lightsecond per "map" second. On the other hand, its proper speed would have been "w" = "γv" ~ 88,000 lightseconds per "traveler" second. By comparison the coordinate speed of a 250 GeV electron in the proposed International Linear Collider (ILC) will remain near "c", while its proper speed will significantly increase to ~489,000 lightseconds per traveler second.