Time Travel Into The Future

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Main Question or Discussion Point

Although we can't technically do this currently, what if we could? What would be a reason to send a person on a mission into the future? If Bob travels at near the speed of light from earth for lets say 5 years and then returns to see Alice. Alice has, and in fact the entire population of earth and everything on it has aged much more than Bob. Bob is now the only one who hasn't aged more than 5 years. Seems like there is no valid reason to ever do this, even if we could.
 

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  • #2
.Scott
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Travelling at near the speed of light is really expensive.
All you want is some form of stasis.

As for a reason - perhaps the traveler needs to outlast a Statute of Limitation. Or he has made an investment that he doesn't expect to pay off for another century.
 
  • #3
.Scott
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Or... Perhaps a brain transplant into your own younger clone.
 
  • #4
Orodruin
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You are time travelling into the future. If you are lucky you have a job there.
 
  • #5
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As for a reason - perhaps the traveler needs to outlast a Statute of Limitation. Or he has made an investment that he doesn't expect to pay off for another century.
Very interesting in both cases!! I can only imagine the laws that might have to be written in the future!!!
 
  • #6
Ibix
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I'm not sure it's a case of "why would you". It's an inevitable consequence of doing a twin-paradox-type journey. So if you want to take a trip to a distant star in your lifetime, you have to accept that your kids'll be dead when you get back.
 
  • #7
.Scott
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I'm not sure it's a case of "why would you". It's an inevitable consequence of doing a twin-paradox-type journey. So if you want to take a trip to a distant star in your lifetime, you have to accept that your kids'll be dead when you get back.
But without relativity, you would never have gotten back at all.

Actually, that's probably not true. By the time you expend that much energy, without c as a limit, you could probably make the trip in a similar amount of time.
 
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jbriggs444
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Janus
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But without relativity, you would never have gotten back at all.

Actually, that's probably not true. By the time you expend that much energy, without c as a limit, you could probably make the trip in a similar amount of time.
Let's assume you want to get to a star 7 light years away, but only spend 1 yr by your clock doing so. Using Relativity, you would need to travel at 0.99c to accomplish this and would require 5.48e17 J/kg of energy to acquire this velocity.
using Newtonian physics, the same energy will get you to a velocity of ~10.5e8 m/sec or just under 3.5 times the speed of light, meaning your trip of 7 ly will take 2 years, or over twice as long as it did using Relativity.
Now let's up this to a 70.7 ly trip in 1 ship year. This requires a speed of 0.9999c under Relativity, and 6.27e18 J/kg of energy. This energy, using Newton will get you up to 11.8 times the speed of light, resulting in a 6 year long trip.
A trip out to 500 ly and back would take 14.14 yrs ship time per Relativity at 0.9999c and 84.9 yrs per Newton for the same energy budget.
 
  • #10
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Travelling at near the speed of light is really expensive.
All you want is some form of stasis.

As for a reason - perhaps the traveler needs to outlast a Statute of Limitation. Or he has made an investment that he doesn't expect to pay off for another century.
Mic drop post.
 

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