GRE Reading Comprehension
According to Einstein's theory of general relativity, objects at different gravitational potentials or observers in motion experience variability in the speed of time. Where gravity is stronger, time moves more slowly; similarly, as an object's speed increases, its relative rate of time passage decreases. Atomic clocks moving at high velocities, such as on airplanes, or at high physical elevation have demonstrated these shifts in time. Even short distances, such as an upstairs bedroom or minor speeds, such as 10 meters per second, can demonstrate variance in the speed of time. This would appear to apply to normal biological processes: one's feet age more slowly than one's head as one's feet are more affected by Earth's gravitational pull. Living at higher altitudes, whether in mountains or in the penthouse of a skyscraper, also ages a body faster than spending more time closer to the ground. Objects in motion, even at a casual pace, would appear to a stationary observer to age more slowly as well. However, although the difference in perceived time is measurable, it is very small—about 100 nanoseconds over 100 years, so it's unlikely to entice anyone to give up their top floor corner office or mountaintop cabin to avoid a wrinkle or gray hair before its natural time.
Based on the information in the passage, with which of the following would the author most likely agree?
- A Research into the speed of time is a frivolous endeavor because it has little application to daily life.
- B It is necessary to use products to care for the skin near your face to keep your body aging consistently.
- C Objects in motion and at a higher altitude experience time shifts more dramatically than objects near the ground or at rest.
- D The faster time moves, due to altitude or lack of speed, the faster the object ages.
- E Einstein's theory of general relativity ought to be revised in light of this new research.
Correct Answer: D