Using a time machine to efficiently answer difficult mathematical problems:<b...
- 2013-02-12 21:10:47+0000 - Updated: 2013-02-12 22:33:26+0000
Using a time machine to efficiently answer difficult mathematical problems:
1. Receive a number N from the future (step 3). Make use of this answer to make money, or whatever you wanted it for.
2. Carefully check whether it is the correct answer to the problem. (Take as much time as you need.)
3. If it is correct, send the answer N back into the past.
4. Otherwise, send N+1 back into the past.
By the Novikov self-consistency principle the only way for the Universe to avoid a paradox is for the correct answer to be the one that was sent. Done. You never need to actually solve the problem, just check that the answer is correct.

### Novikov self-consistency principle - Wikipedia, the free encyclopedia

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Reshared by: Michael Fagan
- 2013-02-12 21:26:38+0000
The real paradox is how would you know the message came from you and also be able to marry that answer to the corisponding question.

The other overlooked issue is the Earth moves and with that when I watch a film like the Time Machine, somehow the time machine is able to be associated with a fixed position on the earth (ie not appear to move accept thru time) yet by doing so it is moving thru space.  If anything you would be like trying to shout into your own ear.
With that in mind, maybe time travel has been invented, it's just that all attempts have yeilded the traveler appearing in a empty part of space as they only traveled thru time whilst the universe carried on moving.  Given the earth moves 18 miles per second in it's orbit alone per second you can start to see that time travel per is often the least of your problems.  You may think yes we could just go back one exact year each time and be at the same spot, whilst that is true in relation to the Sun, Universe wise is an entierly different matter.

Lottery results would be the one everybody thinks of in the outline you state, but which lottery and which set of results would be right.  you could get 6 numbers and not know which week they pertain too.  So I would say that to transmit a answear back in time would be impossible without also transmitting the question as without a way to exactingly marry the two any answer is a question unto itself.  With that Hitch Hikers wonderful answer of 42 does sum up the situation more elegantly.
- 2013-02-12 22:28:49+0000 - Updated: 2013-02-12 22:29:19+0000
I think you are quite correct to point out that there might be a few practical difficulties...
- 2013-02-13 01:44:47+0000
http://www.mathnews.uwaterloo.ca/Issues/mn11103/QuantumBogoSort.php

But surely the velocity is inconsequential, while the acceleration is important. If it travelled with constant velocity there would be no problem! (But yeah, even the same time a year ago [using the correct measure for year], w/ the earth's precession, and perturbations of the orbit... it would be interesting to find out how far off you'd be!)
- 2013-02-13 10:08:39+0000
Very true and with that also impressive understanding for any age.

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