Let's say you have been given a breakthrough chance to time travel into a new invention of a spacecraft where travel through wormhole is possible. Because to avoid the twin paradox, you are only allowed to have 2 hours chance. Because you are in a century where technology gadgets are advance that you must wear an invisible suit to avoid any alternative histories and because at the end you don't want to change your origin universe, you are not allowed to meet to your other self OR kill your own ancestors before you were born. Where, when, what are you going to do ?
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* twin paradox =
To understand this, picture two people, person A and person B. Person A stays on Earth, while person B takes off in a spacecraft. At takeoff, their watches are in perfect sync. The closer person B's spacecraft travels to the speed of light, the slower time will pass for person B (relative to person A). If person B travels for just a few hours at 50 percent the speed of light and returns to Earth, it will be obvious to both people that person A has aged much faster than person B. This difference in aging is because time passed much faster for person A than person B, who was traveling closer to the speed of light. Many years might have passed for person A, while person B experienced a time lapse of just a few hours.
More infos:
http://science.howstuffworks.com/time-travel.htm
http://www.pbs.org/wgbh/nova/time/sagan.html
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* twin paradox =
To understand this, picture two people, person A and person B. Person A stays on Earth, while person B takes off in a spacecraft. At takeoff, their watches are in perfect sync. The closer person B's spacecraft travels to the speed of light, the slower time will pass for person B (relative to person A). If person B travels for just a few hours at 50 percent the speed of light and returns to Earth, it will be obvious to both people that person A has aged much faster than person B. This difference in aging is because time passed much faster for person A than person B, who was traveling closer to the speed of light. Many years might have passed for person A, while person B experienced a time lapse of just a few hours.
More infos:
http://science.howstuffworks.com/time-travel.htm
http://www.pbs.org/wgbh/nova/time/sagan.html