# Paradox which questions time travel to the future

1. Aug 1, 2009

### The Hater

You all have heard of the paradox whereas when you travel to the past and kill your grandfather you should not have existed in the presence whatsoever because you have killed your origins. So far so good...but I thought of another case, which I believe is more interesting since so far the Einstein's equations of time dilation seriously question time travel to the past....but with the paradox I just thought about - even time travel to the future might be seriously under question(not really...I will explain below), but before that - here is the paradox itself:

Imagine that one day time travel to the future is possible.
Given such temptation everyone will like to see the distant future...but at the same time we know that travel to the past is not possible - due to the "grandfather paradox" and because if it was possible, the speed PERHAPS will exceed speed of light, since this is what is shown according to the time dilation simple equations. Now...that means that when you teleportate yourself to the distant future - this is it...there is no way back - you can either stay there or if you don't like it....go even further :). Such as if you don't like 2025...then teleport once again - this time to 2125 hoping that this year will be better(women will be more beautiful). Now...what happens when all people from the present time chose to go to the future? Well...what happens is that if all people go to 2025 - then there will be NO people that have lived in the period 2009-2025, hence the year 2025 will NOT be possible. This is the paradox ;).
Now...a few corrections actually - if all people decide to go to the distant future - then this is actually possible, but since all people have done this - they will see no advance in future.
Here is what happens: If you were the only one to go from 2009 to 2025 - then from the point of view of the people living in 2025 - you would have dissapeared somewhat in the past and the just came out otta the f*** nowhere. If on the other hand you and another 1000 people do the same - then the effect will be the same - only on larger scale. Finally...what happens if today everyone on earth decides to go the year 2025? Well...when we "arrive" in 2025 - we will discover that the only thing which has changed from 2009 to 2025 is actually the trees and the animals :) - since there are no living humans from 2009 t0 2025.
In other words - it will be better if just you and a few friends can travel to the future - since this way you will see immediately what has changed thorough the years that have passed in the meanwhile - otherwise if all people on earth make the jump - then only trees and animals would have been changed :). This is the interesting "paradox" - it's not a paradox in the sense that this doesn't reject the possibility to time travel to the future - but it's interesting to be noted that this is the same like a gold formula - the more people the gold formula - the less valuable it is - if only you knew how to time travel - you can go to the year 2500 and see better computers and hotter girls.

The good news is that neither the "grandfather killing paradox" nor this paradox that I just presented actually question time travel. How come??? Well...the human mind fails to understand that when you change time you change another dimension and there are actually not just 10 or 11 :)...but literally infinite amount of dimensions - so each time you travel you literally create a new reality. Need proof? Well...when the astronauts go to space and come back, they comeback younger. Here is another proof - when object is moving faster and faster it's mass is changed due to...speed. Since mass(ok "energy"...what a word...) can be changed - then as it follows time can be too...it's just a matter of time :).

2. Aug 1, 2009

### The Hater

In other words, the simple time dilation equation:

t' = t*√(1-v2/c2)

If you turn the equation a little bit:

t = t'/√(1- v^2/c^2)

If you want to travel to the year 2104, travelling 12 hours in total, then:

2104 = 43200/√(1- 89875517855706660/89875517873681764)

whereas:
43200 are seconds;
89875517855706660 is speed we are travelling to on 2nd power ;
89875517873681764 speed of light to the 2nd power...);

And here we assume NO acceleration, which is actually not a big problem either.

How time is changed with respect to our speed is(...the derivative...):

Finally, I wrote a short PHP script which lets you calculate the time dilation above...IFthis thread reseives any interest rather than stupid mods changing the category...I will give also C sharp code for a windows application so you can just download it and plug it yorself ;):

The PHP code...for the programmers...just change the numbers and you'll get it...once again...if the thread has any interest later: I will provide a more ser friendly code in c sharp...as a windows form + .exe downloadable file for anyone to download and use it right away not just the programmers.:

<?

$t= 43200;$some=(1- 89875517855706660/89875513077002500);
$t1 =$t*sqrt($some);$z= $t /sqrt($some);

echo "$t1<br>"; echo "$z";

?>

3. Aug 1, 2009

### The Hater

Also....if you want to know "At what speed do I need to travel to go to some year?"

Such as if you want to determine the speed needed to go to the year 2050, travelling a day - then:

(2050 - 2009)*365*(1 - 0.5753424657534246/(2050 - 2009)) = 1/Sqrt[
1 - (x*299792458)^2/299792458^2]
14755 = 1/Sqrt[1 - x^2]
Sqrt[1 - x^2] = 1/14755
Sqrt[1 - x^2] = 0.00006777363605557438
x = Sqrt[1 - 0.00006777363605557438^2]

Which is again about 0.9999 and some more digits the speed of light.
So abot 0.9999*c again.

But, consider that this equations does NOT take into account the fact that 365 days per year are not constant - at least not once in every 4 years :). You can easily change this by adding one-2 things within the equation though...of course.

4. Aug 1, 2009

### junglebeast

We already know from relativity that the speed you travel through time is related to the speed you move through space -- so yes, you can travel to the future. Everyone's doing it. We also know that the speed you travel through space cannot exceed the speed of light, and this puts an upper bound on the speed that you can travel through time.

The universe does not think through possibilities and decree certain things impossible because a paradox may exist. Rather, paradoxes are an indicator that your assumptions are contradictory. In this case I believe that the grandfather paradox is simply a consequence of the fact that time is a measurement of change in state rather than a space-like dimension, and change has no notion of sign -- therefore it is a logical contradiction to go backwards in time, just as it is a logical contradiction to have a positive number less than -1. It is only out of mathematical convenience that we choose to represent time as a 4th dimension, but this is just because in mathematics any arbitrary set of 4 numbers can be referred to as "dimensions."

Last edited: Aug 1, 2009
5. Aug 1, 2009

### leroyjenkens

No, they come back older. Just only a few nanoseconds younger than they would have normally aged sitting on Earth.

6. Aug 1, 2009

### negitron

There is exactly zero evidence of this. It's just a scientific speculation which doesn't even rise to the level of a hypothesis, let alone a theory. Asserting statements is not "proof."

7. Aug 2, 2009

### Ivan Seeking

Staff Emeritus
In fact it is crackpottery that will get a person banned very quickly.

8. Aug 3, 2009

### imiyakawa

Lol best word.

9. Aug 3, 2009

### cristo

Staff Emeritus
This thread seems speculative, at best, and so is done.