define einstein's twin paradox...?

Answer 1

Relativity says that time slows down when moving at high speed, so a person who is traveling at high speed to a distant location will age more slowly than one who stays behind.

But relativity also says that it is not possible to tell who is moving and who is not, so the one who is traveling could say that, from his point of view, he is stationary and the other one is moving in the opposite direction, so HE says that the OTHER one is aging slowly, not himself. The paradox is, how can both say that the other one is aging more slowly?

However, the paradox is cleared up when you note that the twin who really did the traveling would feel an acceleration as he started and stopped while the one who stayed behind would not, so there is no doubt after all which one was moving and which one was stationary.

Answer 2

I have no idea is this helps....

The twin paradox, sometimes called the "clock paradox", stems from Paul Langevin's 1911 thought experiment in special relativity: one of two twin brothers undertakes a long space journey with a high-speed rocket at almost the speed of light, while the other twin remains on Earth. When the traveler returns to Earth, he is younger than the twin who stayed put. Or, as first stated by Albert Einstein (1911):

If we placed a living organism in a box ... one could arrange that the organism, after any arbitrary lengthy flight, could be returned to its original spot in a scarcely altered condition, while corresponding organisms which had remained in their original positions had already long since given way to new generations. For the moving organism the lengthy time of the journey was a mere instant, provided the motion took place with approximately the speed of light. (in Resnick and Halliday, 1992)


This appears to be a paradox if one expects that, according to relativity, either twin may validly claim to be "at rest", and thus each expects that the other twin will age slowly. Like most paradoxes, this occurs because of faulty assumptions. This one happens because one twin undergoes acceleration while the other does not, something that was not taken into account when this twin-paradox story was invented.

Answer 3

Well, actually it is not a paradox. It has to do with the physical body of a person having the capacity to age. Let's take a look at two people. The first is Josephene, who is twenty years old, and will remain on earth while her twin brother, Joe, heads to the nearst star (three light-years away) testing out his newly invented space-drive.

Joe begins his trip. His space ship is instantly able to accelerate to the speed of light (can't be done in reality, because when a mass accelerates to the speed of light it converts into electromagnetic energy). Three years later he arrives at the star system and spends one year there investigating it. Then Joe heads home at the same speed he began. When Joe arrives home he finds that Josephene appears to be twenty seven years old. Joe appears to be only 21 years old. What is the reason?

To begin, were Joe to have begun his journey with a hot cup of coffee and a cold sandwich, when he arrived at the star system three light-years away, the coffee and sandwich would be the same temperature when he arrived as when he left. They, as Joe, would not have changed physically, because the energy comprising his body would have had no potential movement at a right angle to direction of travel.

Travel at this speed is similar to being frozen near absolute zero in liquid helium. There is no manner whereby molecular change is able to take place. Not only would the body mass moving near the speed of light be unable to have variable energy values, the thought process of the person would also be frozen. So, Joe who whould arrive at a star system three years later, would have no thought other than having started. There would be nothing between.

At http://360.yahoo.com/noddarc there is a writing, "The Problem and Repair of Relativity" giving an easy to understand further explanation of this.

Answer 4

This is a little known story but Einsteina nd his Cousin, Earl were supposed to go on this double date and when they showed up they were twins. Earl was supposed to go out with Lilly and Earl was supposed to go out with Billie, well the girls messed with them and said to call them Dox and they never could figure out who was who... this is the Einstein pair a dox.