19573
By Science News
In your article you refer to a standard concept of a person speeding “in a rocket traveling slightly less than the speed of light” and say that “motion at such enormous speeds drastically slows the clock for the traveler.” That reasoning, which is common, troubles me. If the traveler is traveling speedily with respect to an observer, then, clearly, the observer is traveling speedily with respect to the traveler (who is observing the observer). Since all motion is relative, why shouldn’t the observer’s clock slow down as observed by the traveler?
Arra Avkain
Fresno, Calif.