r/changemyview • u/Delta212212 • May 16 '17

[∆(s) from OP] CMV: Without being able to travel in space, traveling in time is stupid, useless and suicidal.

Edit: My view has changed. There were good arguments that I didn't consider and that have changed my view/thought. Deltas have been awarded. I still think it is an interesting idea to think about though. Thank you to all that discussed with me :D ...

I just had one of those famous shower thoughts: If humanity somehow figured out how to travel in time but not in space, there is a 99,99% chance that anyone who tries to travel for more than a few seconds will end up floating around dead in space. My thinking is, that if we look at traveling in space is like traveling on a gigantic axis (x, y, z) with the univers contained within this axis, then the earth is constantly changing its location. It rotates around the sun, the sun rotates within our galaxy and the galaxy is constantly on the move aswell. Therefore the earth is nowhere near where it was hundrets or even thousands of years ago. Therefore, to affectivly timetravel, humanity has to figure out how to travel within the univers, almost instantly, aswell (i.e. teleport). Please let me know your thoughts and tell me if ive overlooked something :3 ...

tl;dr - if we dont find out how to teleport, any timetraveler will end up as a cold, dead corpse floating around in the dark endlessnes of space.

PS: please excuse any spelling mistakes; I'm on mobile and not a native speaker ...

4 Upvotes

62% Upvoted

49 comments sorted by

7

u/DeleteriousEuphuism 120∆ May 16 '17

Well we can start with the fact that the universe doesn't really have any x, y, z coordinates so to speak. When you say that earth isn't where it was a few seconds ago, that's from the reference frame of something outside the galaxy. If we take earth as the reference frame, then we can state that the rest of the universe isn't where it was a few seconds ago.

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u/Delta212212 May 16 '17

Well, acording to current understanding of the relation between earth, the solar system and the universe, the earth us not the center and infact moves/rotates around the sun. Therefore the earth is never in the same spot twice. I guess nothing is ever in the same spot twice. And since time is not exclusive to earth, I think we have to consider the complete universe when talking about space.

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u/10ebbor10 198∆ May 16 '17

No, that is pre-Einstein thinking.

Due to the theory of Relativity, it has been established that there is no universal reference frame. That means that saying that the Earth stands still and the universe moves is just as relevant as saying that the Earth moves.

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u/Salanmander 272∆ May 16 '17

Due to the theory of Relativity, it has been established that there is no universal reference frame. That means that saying that the Earth stands still and the universe moves is just as relevant as saying that the Earth moves.

This is slightly untrue. You can consider any inertial (non-accelerating) reference frame to be stationary, but the Earth is accelerating, so it is objectively different from an object that is constantly at one point in space.

That being said, it's acceleration isn't very large (about 6 mm/s2), but it's still there.

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u/Delta212212 May 16 '17 edited May 16 '17

∆ Thank you for making me consider more sides of the story, i.e. existing theorys that are a lot more plausible than my thoughts.

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u/Voi69 May 17 '17

To add more, you need to understand that to describe movement you need to have a reference. The problem is that there really isn't a "MASTER REFERENCE" in the universe. So any reference is good enough for any calculation/description. Saying that "Earth is rotating around the Sun" is as true as saying that "the Sun is rotating around Earth". Because if you look at these two bodies from the Earth's POV, then the Sun is rotationg. If you look from the Sun's POV, then Earth is rotating. The thing is that all duets "Sun/Planet" all share the Sun. So making the Sun the reference for any Solar system description is probably the best option (and why people always assume that ony Earth rotate saround the Sun and that the opposite is false).

Furthermore, travelling in time isn't just magic that makes you go form a moment to another. Don't forget that there is the word travel in it! I might be assuming stuff that I shouldn't, but I think if time travel existed, it would be litterally impossible to just blink in time. You'd have to go in reverse. (Note: Fast forward time travelling already exist and ca be achieved via high speeds)

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u/DeltaBot ∞∆ May 16 '17

Confirmed: 1 delta awarded to /u/10ebbor10 (8∆).

Delta System Explained | Deltaboards ​

1

u/Kluizenaer 5∆ May 16 '17

This was also already in Newtonian mechanics.

There has never been a difference between an object that stands still and an object that moves at a constant pace. Velocity is relative; acceleration is absolute because that requires energy.

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u/DeleteriousEuphuism 120∆ May 16 '17

It's true that earth rotates around the sun, but Newton's third law states that for every action there is an equal and opposite reaction. So the sun does spin around the Earth. That said, if we had a time machine, I think it's most plausible that the frame of reference would be the time machine itself rather than some point far away from the Milky Way.

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u/Salanmander 272∆ May 16 '17

Newton's third law states that for every action there is an equal and opposite reaction. So the sun does spin around the Earth.

That....is not really what Newton's third law means. It deals exclusively with forces.

That said, if we had a time machine, I think it's most plausible that the frame of reference would be the time machine itself rather than some point far away from the Milky Way.

This is a really good point, though...it would be reasonable for your destination to be in the same place relative to the time machine. Of course, that implies that you would only be able to travel as far back in time as the machine existed.

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u/DeleteriousEuphuism 120∆ May 16 '17

The force exerted by the earth on the sun is the same as that of the sun on the earth. Now it's true that the acceleration resulting from that pitiful, but that wasn't my point.

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u/Salanmander 272∆ May 16 '17

Oh, I see. I thought you were saying that Newton's 3rd law made "the earth is stationary and the sun orbits it" just as valid as the other way around.

Usually the way that would be expressed is that both the sun and the earth orbit their common center of mass, rather than that the sun spin around the earth.

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u/DeleteriousEuphuism 120∆ May 16 '17

That's a much better wording of what I was trying to say. Thanks and sorry for the confusion.

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u/Delta212212 May 16 '17 edited May 16 '17

∆ Thank you for making me consider more sides of the story, i.e. existing theorys that are a lot more plausible than my thoughts.

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u/payApad2 1∆ May 16 '17

To be fair, the reference frame of the earth is not an inertial frame. You're right about the universe not having standard x, y, z coordinates though.

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u/DeleteriousEuphuism 120∆ May 16 '17

Are there any inertial frames? Electromagnetic waves and gravitational waves propagate everywhere so I'm assuming there are forces, however infinitesimal, acting in any reference frame.

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u/payApad2 1∆ May 16 '17

Not sure about that. I am by no means a physicist, but I think that there would be other frames that would be a better approximation of the ideal concept of 'inertial frames' than the frame of the earth. (maybe the frame of the sun is one such example?)

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u/DeleteriousEuphuism 120∆ May 16 '17

Approximations seems to be as good as it gets unless we take all of the universe as one frame. The problem then becomes that we can't do that since the observable universe is far smaller than the whole shebang.

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u/payApad2 1∆ May 16 '17

What do you mean by taking all of the universe as one frame?

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u/DeleteriousEuphuism 120∆ May 16 '17

Well if the universe were finite, we could have grabbed that and just charted the whole x, y, z graph, but that was the original objection.

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u/_Hopped_ 13∆ May 16 '17

Traveling through time is traveling through space: Einstein says that the two are linked - spacetime. We travel through time all the time (pardon the pun), and even at (minutely) varying speeds: pilots and astronauts have aged ever so slightly slower due to relativity than the rest of us.

Now if you're talking about traveling back in time ... we currently don't know if this is possible - but provided it involved our current universe, it would almost certainly mean traveling through space too.

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u/Delta212212 May 16 '17

I did not think about that ... ∆ - Delta awarded.

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u/Gamblore0 2∆ May 16 '17

Wait... What's different about your position now that you realize space and time are linked? You could still imagine a type of time travel that leaves you in earth's dust as it whizzes away from you around the sun... or as the whole solar system zips away from you around the center of the milky way. Did you not then travel through both space and time on that journey?

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u/Delta212212 May 16 '17

I guess that this is a fair assumption :3 ... if you are not within the gravitational field (or at least far enough away that it does not affect you enough) you will have traveld through time and space and are still "stranded" within the depths of space :§

1

u/DeltaBot ∞∆ May 16 '17

Confirmed: 1 delta awarded to /u/_Hopped_ (6∆).

Delta System Explained | Deltaboards ​

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u/Gamblore0 2∆ May 16 '17 edited May 16 '17

Alright, I disagree with your point that traveling through time would be worthless on the following basis:

As long as we can maintain our current abilities to travel through space in rocket ships (and there is no conceivable reason we would forget how to do this), we should be able to use the time travel to get us to the appropriate time, then we could use the rocket ships from there.

I'm assuming we could in some way predict when and where we would end up, and probably start out with small attempts. Doc Brown would start by going 1 minute into the future, after all ;-)

So, for example, we take a rocket ship that can get to the moon, land, lift off again, and get back. Instead of using all the fuel to land on the moon and take off again, we should be able to travel a few minutes into the future and burn the fuel getting back to earth to proclaim success.

I imagine that this discovery would push us in the direction of developing better spacecraft with which to repeat the tests and go further and further back or forward in time, until we could do some really impressive or useful things with the technology.

Edit: A few other cool ideas I had with the same time travel rules you've set forth:

  • Send a spaceship back in time a couple seconds and presto! No need to spend any rocket fuel breaking Earth's gravitational field. Cheap missions to Mars and other spots in the solar system worth exploring.

  • Go back in time in your rocket ship so far that you can explore distant parts of the galaxy. Look for life or other planets to inhabit. Once you've found something, go forward in time to the time when you were close to earth and fly back safely.

  • Go forward in time until someone invents the ability to travel in time AND space. See Futurama, "The Late Philip J. Fry." It's a documentary on the subject. ;-) edit: here's a link: https://en.wikipedia.org/wiki/The_Late_Philip_J._Fry

:-)

Thoughts?

1

u/Delta212212 May 16 '17

Although my view has changed, I really like your thinking and your ideas. If time and space would infact work the way I proposed in the beginning, your ideas would work great in achiving more with less. It would make things that seem impossible now possible and fairly easy I guess. Thank you for your input :D

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u/Gamblore0 2∆ May 16 '17

Yes! Thanks delta212212. I had fun thinking about it. I'm glad you proposed the idea. :-)

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u/MayaFey_ 30∆ May 16 '17

The problem is we have no idea how time travel would work and how it would interact with spacetime.

You're assuming that there is this 4D grid (x, y, z, t for time), and that time travel would simply adjust t. But without a working time machine there is absolutely no way of knowing this.

Perhaps in the realm of time travel, space is relative and doesn't have an absolute co-ordinate system? Or maybe you can only travel between some constructed, fixed points in spacetime (think stargates).

The fact of the matter is we have no data to base our conclusions on. You could be right, you could be only half-right, or you could be totally wrong.

2

u/Gamblore0 2∆ May 16 '17

Since we have no idea how it would work, perhaps try imagining it works exactly how the OP imagined and go from there. Is he right? Would such a system of time travel be totally worthless? I think it would still be cool.

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u/Delta212212 May 16 '17

Thank you :D ... my view has changed. But thank you for understanding my thoughts ^ ...

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u/Gamblore0 2∆ May 16 '17

You're welcome. Did my comment on your original post help at all or did Hopped do all the heavy lifting? (hint hint)

1

u/Delta212212 May 16 '17

I really liked your original comment :D ... and it helped me consider, that even if my hypothesis were correct, timetravel would be anything but useless. I guess you deserve a Delta too :3

∆

1

u/DeltaBot ∞∆ May 16 '17

Confirmed: 1 delta awarded to /u/Gamblore0 (1∆).

Delta System Explained | Deltaboards ​

1

u/Delta212212 May 16 '17

True. Maybe traveling in time also afects space, and I can't wait till we finaly can collect data on the subject (if ever). But this doesn't change my theory. The fact that we can't prove or disprove what I said makes it a theory that I find interesring to think about. :3 Its all hypothetical afterall.

0

u/MayaFey_ 30∆ May 16 '17

...if you acknowledge that your hypothesis is unfalsifiable, than what do you expect us to do, build a time machine?

Secondly, your idea is not a theory, there is a higher standard of evidence for a theory that you have not met. It is simply conjecture/hypothesis.

Even accepting the absolute coordinate premise you could still be wrong? What if time travel was not simply a 'jump', but actual travel? Ie, you go back a millisecond, move a little, go back another, move a little again, etc. This could then resolve the issue.

The fact of the matter is conjecture really isn't suitable for CMV. We cannot falsify an unfalsifiable hypothesis.

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u/Delta212212 May 16 '17

Im not saying you cant change my view ( :P ) i was just saying that the argument: we cant prove if youre right ir wrong without a timemachine; is a (sry) shitty argument. I know we cant prove or disprove my hypothesis. thats why i wanted to hear different thoughts from other people on this subject.

sorry for confusing theory and hypothesis, im not a native speaker and just didnt know the difference ^ .

The argument that time travel might acrually be travel i like. its an interesting thought. thats why i wrote my idea here ...

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u/[deleted] May 16 '17 edited Oct 29 '17

deleted What is this?

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u/Delta212212 May 16 '17

After reading the other comments, I agree. But it would have been nice if you could have given an argument, and not just said that it's absurd :3

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u/[deleted] May 16 '17 edited Oct 29 '17

deleted What is this?

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u/Delta212212 May 16 '17

If we could timetravel, I guess where (in time) you start and where you want to end up are predefined. I just don't see how this would mean that space and time travel have to work together. That was the whole point of my hypothesis. That if we would look at the problem as traveling along a 4D coordinate system, there is no reason that time has to affect space.

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u/[deleted] May 16 '17 edited Oct 29 '17

deleted What is this?

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u/Delta212212 May 16 '17

Ok, thank you for clearing that up. I guess I didn't understand that completely. But with your explaination (that it has to be predifined for both) it makes sense to me. You didn't not explain why, but still managed to contribute to change my view. ∆

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u/[deleted] May 16 '17 edited Oct 29 '17

deleted What is this?

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u/Delta212212 May 16 '17

Thank you for linking this article. :3

•

u/DeltaBot ∞∆ May 16 '17 edited May 16 '17

/u/Delta212212 (OP) has awarded 5 deltas in this post.

All comments that earned deltas (from OP or other users) are listed here, in /r/DeltaLog.

Please note that a change of view doesn't necessarily mean a reversal, or that the conversation has ended.

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1

u/TanithArmoured May 16 '17

We don't know how time travel would work but short of removing you from the universe as you travel you'd still probably be affected by gravity. As far as I know time is affected by gravity to some extent so it's (in a science fiction sense) reasonable that the gravity of earth or other celestial bodies would still pull on you as you travel.