Time Travel Theory


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Kliph
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Message 1246051 - Posted: 14 Jun 2012, 18:39:14 UTC

Hello all,

I realize the concept of time travel is a little out there but this board is full of intelligence and lacking in trolls so I feel like it's a good place for my question.

Time travel would allow you to move through time, but not space. Thus, you could travel to New York City in 1900, but only if you "depart" from NYC in your current time.

If I understand this correctly, you remain at the same point in space, but travel in time.

This where I'm confused. Earth is moving through space. If you travel back to NYC in 1900, you'd end up somewhere in the cosmos where NYC was at that point in time and Earth won't be there.

Since Earth is constantly moving through space, it would be impossible to get back to that same point in space and have Earth be there. Right?

...just thinking.


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Message 1246190 - Posted: 14 Jun 2012, 22:18:32 UTC

Just don't shoot your father.

Kliph
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Message 1246197 - Posted: 14 Jun 2012, 22:34:54 UTC - in response to Message 1246190.

Just don't shoot your father.


Ha! However, if I did that, I wouldn't have been able to be there to do it in the first place.

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Message 1246232 - Posted: 15 Jun 2012, 1:23:08 UTC - in response to Message 1246051.

The problem with time travel is that time travel cannot be tangibly proven... Time travel is a signal as the surface response of the human form to its environment is...

:)


tsk tsk...
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Message 1246233 - Posted: 15 Jun 2012, 1:23:57 UTC - in response to Message 1246051.
Last modified: 15 Jun 2012, 1:24:22 UTC

"Time travel is a forward escape into a new past..." Terrence McKenna
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Electrons started spinning, electrons are still spinning and electrons will be spinning tomorrow to the best of our knowledge therefore either change in acceleration is persistent or friction is fractally less than understood.

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Message 1246329 - Posted: 15 Jun 2012, 6:38:45 UTC

Before you can discuss time travel, you need to define what time itself is.

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Message 1246359 - Posted: 15 Jun 2012, 9:09:13 UTC - in response to Message 1246051.
Last modified: 15 Jun 2012, 9:10:15 UTC

You cannot travel back in time since the principle of causality provides a paradox. You cannot travel forward in time either since that makes no sense.

What is possible is that you can take a trip at a very fast rate of speed and return having aged less than those who remained behind. You are not traveling back in time; you are only aging more slowly. All other notions of time travel are fiction.

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Message 1246360 - Posted: 15 Jun 2012, 9:37:21 UTC
Last modified: 15 Jun 2012, 9:42:21 UTC

Time is the measurement of the duration of an event from beginning to end, measured in arbitrary units. e.g. we can say it took X hours of elapsed time to read a certain book.

Travelling back in time to things that have already happened in "OUR" past, then travelling forward again to "OUR" present, may be possible.

In 2075, someone from "THEIR" present may be able to travel back to "OUR" present, but they wont be able to travel forward from "THEIR" present. Any more than we could now in "OUR" present, travel forward to their present in 2075.

If things haven't happened yet in "YOUR" present you cant travel forward to them.

Putting it more simply, I can replay last weeks TV program now, because I recorded it then. I can't record next weeks program now because it hasn't been transmitted yet. Next week I can replay next weeks program then, because it will by then be in the past and not in the future.

OK paradox No.1 - Someone from 2075 materialises here in 2012. They offer you a lift back to their time in their time machine. Would you instantly disappear?

Somebody buy me a beer please!

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Message 1246527 - Posted: 15 Jun 2012, 18:16:14 UTC - in response to Message 1246360.

Interesting stuff here. I should have noted that this is more of a pseudo-science topic...especially since I'm in the middle of Carl Sagan's The Demon Haunted World. Shame on me.

How do we define time? Watchinmg the Through the Wormhole episode "Does Time Exist" really gave me a lot to think about.

A few years ago some MIT students (I'm in the Boston, MA USA area) erected a monument that asked time travelers from the future to go back to the statue at a specific date & time. The date & time passed without incident. I wonder if the monument is still up? That's a key part of the whole expiriment!

Basically I was fixated on when time traveling from point to point, how would you even define that point? The Wikipedia article doesn't cover that, haha.

This thread is what happens when you read the Fermi Paradox article on Wikipedia and start following the links in the article to other topics. Just be lucky I didn't start a thread asking if we're living in a simulation!

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Message 1246852 - Posted: 16 Jun 2012, 8:31:37 UTC

OK try this one. A time traveller from 2075 appears and stands beside me. We are both human beings looking just the same. BUT he can travel forwards to 2075, and I can't, because for me, certain things haven't happened yet. So what would be the fundametal difference between us. Would it be in our brains? Could it be determined by instruments?

I wonder if this links in to people convinced thatthey have lived before in the past. You never hear of people believing they have lived (before) in the future.

Hurry up with that beer :-)

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Message 1247838 - Posted: 18 Jun 2012, 7:20:11 UTC - in response to Message 1246051.
Last modified: 18 Jun 2012, 7:38:19 UTC

Hello all,

I realize the concept of time travel is a little out there but this board is full of intelligence and lacking in trolls so I feel like it's a good place for my question.

Time travel would allow you to move through time, but not space. Thus, you could travel to New York City in 1900, but only if you "depart" from NYC in your current time.

If I understand this correctly, you remain at the same point in space, but travel in time.

This where I'm confused. Earth is moving through space. If you travel back to NYC in 1900, you'd end up somewhere in the cosmos where NYC was at that point in time and Earth won't be there.

Since Earth is constantly moving through space, it would be impossible to get back to that same point in space and have Earth be there. Right?

...just thinking.




Yes, because Earth is constantly moving through space you are correct in what
you stated quoted below...
...If you travel back to NYC in 1900, you'd end up somewhere in the cosmos where NYC was at that point in time and Earth won't be there.


Time in the universe relies on motion for it is actually a point in space and
time only shifts forwards because our position in space has moved forwards.
So every second of time that passes is actually a measurement of the distance
we have moved in space (space time) but we call it time though. Actually, time
as we know it does not exist for it has no dimension to it. It is a perception
we encounter brought about by having a memory. If time possessed a functional
dimension then we would be able to move along it both forwards and backwards but
it doesn't. This is the reason why we can not achieve and will never achieve the
ability to time travel either forwards or backwards.
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Message 1247854 - Posted: 18 Jun 2012, 9:32:08 UTC
Last modified: 18 Jun 2012, 10:03:26 UTC

Actually, time as we know it does not exist for it has no dimension to it. It is a perception we encounter brought about by having a memory


Time is the measurement of the duration of an event from beginning to end. So it is more correctly elapsed time, and that can be measured in what ever units you choose to call them.

If I said to an ET that my car could do 100 MPH that would mean absolutely nothing to them. But if I said that it could cover a distance of 1/249th of the earths circumference in 1/24 of the duration of one complete rotation of the earth, they could go and measure those quantities in whatever of their own units they chose, and understand the speed I was talking about.

For everyday use we have chosen to divide the duration of one complete orbit of our planet around our star, the sun, into approximately 365 parts which we call a day. Those days are again divided by 24 giving what we call hours, which are divided again by 60 to give minutes, and finally divided by 60 again to give seconds, our smallest unit of elapsed time.

But for science that is not accurate enough since we know the the earth's rotation and orbit are slowing down. Since 1967 the second has been defined as the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom. In 1997 CIPM added that the periods would be defined for a caesium atom at rest, and approaching the theoretical temperature of absolute zero, and in 1999, it included corrections from ambient radiation.

ET's elsewhere may have entirely different methods of measuring and recording durations of events.

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Message 1247865 - Posted: 18 Jun 2012, 10:09:50 UTC

This where I'm confused. Earth is moving through space. If you travel back to NYC in 1900, you'd end up somewhere in the cosmos where NYC was at that point in time and Earth won't be there.[quote]

Since Earth is constantly moving through space, it would be impossible to get back to that same point in space and have Earth be there. Right?

From the viewpoint of an outside observer on another star system, the earth is moving through space relative to them. If they went back in their time, then they would see the earth in a different position in space.

For someone on the surface of the earth, who goes back in time, they don't move relative to the earth itself, so if the earth ends up in a different position in space so will they with it.

Hasn't this all to do with event horizons in the Relativity theories?

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Message 1247869 - Posted: 18 Jun 2012, 10:26:56 UTC - in response to Message 1247865.

Time is an illusion by which we order events in our lives.

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Message 1247873 - Posted: 18 Jun 2012, 10:32:11 UTC

Time is an illusion by which we order events in our lives.

It's certainly no illusion when they call last orders in my local pub!

But seriously, I don't believe that time travel as popularised by sci fi is actually possible. If it was, wouldn't people from the future have come back to tell us how to do it?

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Message 1247976 - Posted: 18 Jun 2012, 17:27:43 UTC - in response to Message 1247869.

Time is an illusion by which we order events in our lives.

Will', It's quite difficult for humans to accept this for the passage of
time has always been perceived to be a more physical event to them.

Like you, to me time is an illusion and I wounder because we can use this illusion in a very
constructive way is what gives us humans this thing called intelligence.
We are not on our own here with our line of thinking here about time, plenty
of scientists share our view here too. It is only a line of thinking though
but I feel pretty certain that it may well become the accepted line on this
subject one day. Time is inextricably wound up in time-space and if time was to
possess a dimension then this dimension collapses as soon as it is created for
it leaves no trace of it's existence. Meaning that time past, time present and
time future all exist at the same point in time-space. Perhaps what happens is
that the universe consumes time as we travel through time space. So as the
universe expands we consume the time part of space-time and as we go on
we just leave the space element of space-time behind us. So as long as the
universe is expanding, or collapsing, we create this illusion of time.
As regards time travel, then simply to do so we would have to take the
whole of space-time and the whole of the universe with us too, you just simply
can't do that...plus, no doubt, to travel backwards in time light would have
to travel backwards too. Us humans can not isolate ourselves from universal
space-time, "Laugh and the world laughs with you" is a well known saying and
for our universe we have one, "Move around in time and the universe will have
to move with you". Time travel is an impossibility.



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Message 1247990 - Posted: 18 Jun 2012, 17:46:16 UTC

plus, no doubt, to travel backwards in time light would have
to travel backwards too.

Well now, "things" would necessarily need to be in exactly the same state that they were back then, at the time you went back to, for them to be relevant. So if then, science hadn't invented a time machine, how could you be there?

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Message 1248084 - Posted: 18 Jun 2012, 20:45:13 UTC

Wow, some really interesting comments here. Thank you!

I liked the concept that the universe consumes time. And that you never hear of people saying that they have lived (before) in the future.

The ideas of seconds/minutes/hours have been invented by humans. However, wouldn't humans notice "time" passing without needing to reference a clock? I don't need to look at my watch to "know" it's been a few hours since I last looked at my watch.

Time travel does seem like an impossibility. BUT...
What if it's invented in the year 5,000? Why go back to the boring old 2000's.

Why go "back" in time at all? Would going forward be much more interesting?

Maybe it's developed and the first time it's actually used it's realized to be just too powerful and dangerous?

Maybe the act of trying to warp time & space breaks the universe?

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Message 1248278 - Posted: 19 Jun 2012, 7:29:27 UTC

Why go "back" in time at all? Would going forward be much more interesting?

Both I feel would be very interesting to experience, it would be the ultimate
experience. But since the universe can't split time past, present and future
apart into separate events we can only experience then the notion of time present.
If time possessed a dimension then we could at least travel backwards but because
it does not then time as we know it does not and can not exist other than in
our imaginations.

____________
The Kite Fliers

--------------------
Kite fliers: An imaginary club of solo members, those who don't yet
belong to a formal team so "fly their own kites" - as the saying goes.

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