Question

Explain in 200 Words the question below:

A Twin Who Makes A Long Trip At Relativistic Speeds Returns Younger Than Her Stay-At-Home Twin Sister. Could She Return Before Her Twin Sister Was Born? Defend Your Answer.

N/B : When You Defend Your Answer, Explain The Normal Twin Paradox, Then Use That Explanation As Part Of Your Answer To The Question

Answer 1

This question can be explained using the special theory of relativity. The twin paradox in special theory of relativity is a hypothetical experiment in which there are two twins. One of them stays on earth while the other leaves for another galaxy and returns home in a round trip. According to the special theory of relativity a moving body ages less so the twin who makes the trip should be younger . But the motion is relative, each twin is in motion relative to other so who will be younger. This is called the twin paradox. Its resolution is that the twin who makes the trip does not moves at a constant speed. He first accelerates to reach a maximum velocity and then he decelerate, takes a turn then accelerates and comes home. When he makes a turn to come home, at that time he jump from one frame of reference to another frame of reference and this asymmetry is the reason we consider him to be the moving twin and thus his age will be less as compared to the twin who stays on earth. Now the twin cannot come before his birth because the maximum speed he can take is close to the speed of light (not equal to the speed of light) so he will still will spend some time. He can slow the time but the time cannot be reversed. Another main law of nature that will violate if he comes before his birth is the law of causality. Which says the effect of any event cannot happen before the cause of an event. Like a bullet cannot kill a person before it is fired from a gun.