As someone who watched Interstellar, I would simply rely on gravity and love
this post was submitted on 08 Sep 2025
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Two Sentence Horror
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Two Sentence Horrors.
The title should be the first sentence, while the body should be the second.
Keep it spooky.
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You have to realize that you shouldn't have left. What you were looking for was here all along.
In case anyone else was wondering:
"Earth orbits around the sun at a speed of 67,100 miles per hour (30 kilometers per second)."
So 9000 kilometers away in 5 minutes.
But then the milky way spins at around 200-250 km/s, so there's that displacement also.
If a time machine only travels through time and not space, would parts of the time machine travel through time at miniscule differences such that the power source is hundreds of kilometers away from the controls and thus the machine wouldn't work beyond the initial activation?
One final twist on the displacement, the milky way is also being moving away from its origin location of the big bang.
And in a gargantuan coincidence of improbability all these displacement vectors just so happened to cancel out perfectly the time the time machine was activated. Leading to the catastrophe that was the second activation…
the origin location of the big bang
And that location is... ? :)
gestures vaguelly
Minor correction: changed 'the origin location' to 'its origin location'
Wherever the blue shift stops when measuring cosmic background radiation I suppose.
I still take issue with the wording "the milky way is also being moving away from its origin location of the big bang". The milky way isn't moving away from its origin location, everything else is.
And from every other point of reference, the milky way galaxy is moving away from it.
And then also, everything within the milky way is moving away from itself.
No, that's the whole point of a time machine. You need it to ignite and launch within a single quantum (or rather, as a hint, each of its action must last that long, you can still have multiple stages).
This notion has always bothered me, so I thought a lot about it just now: A fundamental principle of Einstein's theory of Special Relativity is there is no privileged reference frame. That is, all measures of an object's motion are relative to other objects. There is no same-spot-in-space-but-5-minutes-ago for all observers. That's going to vary by reference frame.
See, the time machine before the trip does not move relative to Earth, but does move relative to the Sun, to the other planets, to the galactic core, et cetera. If we stipulate that going back 5 minutes equals a certain ∆x, that establishes the Earth's reference frame as privileged, and then observers in those other reference frames (given ∆t = -5 minutes) would calculate different values for c.
The way to avoid breaking physics is to recognize that observers in other reference frames could see what the distance that a trip of 5 minutes back in time means in Earth's inertial reference frame, but they'd calculate a different ∆t. But then, that means that time is just like space— all relative. How would a machine gain traction on it, what with no guideposts or reference points, no coordinate system with which to locate a target time? How would it measure out 5 minutes, except by internal chronometer? Then, going back in time 5 minutes would take 5 minutes for the occupant of the machine. (In this case, the machine going backwards in time would physically collide with itself-prior-to-the-trip in the first moments. Whoops.)
Assuming some magic technology that lets a time machine calculate some target time and pop out of existence now and pop into existence then, like in most sci-fi, it would have to calculate a destination location at which to pop into existence, too. Space and time are inextricably linked after all. (The Earth is a pretty big local mass, it should be easy to detect with... magic.) By coincidence, the time machine would also be a teleporter, and known physics would just be bits of rubble on the floor.
Anyway, other details that bother me: How does the time travel mechanism discriminate between machine and non-machine matter? Does it take a bubble of soil and air with it in order to be safe? Does the travel process necessarily sap the machine's momentum, or at least increase its mass? If not, it'll keep moving at the same velocity before and after the trip, and the Earth will never catch up.
My man, the earth is rotating, it's not a valid reference point anyway.
But yea, best I have made it as far as time machine is concerned is approximating the trajectories, or even just mapping them for this specific purpose if the jump is not to a time previous to my creation, and bringing along the whole acceleration necessary to not get instantly smashed by unmatching motion on a galactic scale.
The fisical overlapping of matter I found can be solved by swapping the landing and the coming portion of space. Sure you may end up with stuff back in the lab, but it's a lot better than the vacuum and the atomic bomb that would trigger right after. And of course there's the simmetrical issue of pushing stuff out of the way where you land.
Given that, I never manager to get it to work in bursts longer than 0,0004 ms so I gave up. I also ran out of cats.
Time travel is possible, it's just deadly, and that's why we don't see travelers.
Something something mirror.
But... What if you were enclosed in a blue safety box?
This is why I think the best time travel machines are just spaceships. You could simply assume that when it moves through time, it also keeps up in space. It already gets around relativity; you can suspend your disbelief for it traveling really fast, too.
I am obliged to mention The Three Body Problem and the rest of the trilogy, by Liu Cixin. It's an excellent work of 21st Century sci-fi; I haven't watched the TV adaptation though.
It's been years since I read them, but I don't remember any time travel.
That's common, but you actually read it 3 month ago.
If it is approaching then that implies momentum is not conserved.
So even if you managed to allow for the various orbital displacements you would instantly be pancaked on arrival.
Some poor sucker is stuck in an endless jerk-off
The desire for extended gooning sessions is probably how we'll end up figuring out time travel
w-what