Yo momma so fat she attracts time travelers from the Andromeda Galaxy.
But I don't think frame dragging solves the problem, at least not without a complete rearrangement of relativity, in which case you don't really need frame dragging.
The problem is that frame dragging occurs in the local environment - if you're being dragged along with a frame, you're not traveling at any unusual vector through time.
Time travel necessarily deviates from the spacetime path of the frame, otherwise you'd just be traveling with the frame as normal. And if you deviate from the path of the frame, then ordinary frame dragging isn't going to help you. Of course you could perhaps invent some sort of more spooky frame dragging to handle this case, but it wouldn't have the same physical basis.
I think many people have already identified this. Considering spatial movement is dimensional movement (as time is) it isn't hard to imagine this is compensated for similarly. You're already bending space time to move around in time, just keep bending it to move in space.
Big deal that fiction doesn't actually detail this, it adds nothing to the narrative.
It's only a communications device, not a transportation device but it does consider the movement. The signal is sent to the same point in space where the machine currently is, the range limit is how far away from that point you can be and receive it.
Even if you solve the problem of where to go, I don't know how you ensure that location is clear of other stuff. If a bunch of air molecules suddenly appeared inside you, I don't think you'd enjoy it.
This might be why time travel in Terminator movies creates the sphere of energy right before the traveler appears: it clears out the space. But then why doesn't the person experience a moment of disruption being inside a perfect vacuum?
Seems silly to namedrop Doctor Who without acknowledging that the name of the time machine in the series (the Tardis) is an acronym for Time and Relative Dimensions in Space - which, you know, kinda directly addresses the allegedly unaddressed spatial problem outlined in the article.
In HG Wells' case, the Time Machine is resting on the ground and travels with it. It doesn't ever travel back in time to before it was built. i.e. the occupant only travels in time to where the machine already exists.
The machine no more needs to calculate its motion through space as it travels through time than a rock or an old building does.
You are missing the point. Once you are free of space time there is no gravity holding you to the surface of the planet, therefore staying on the surface of the planet requires a propulsion system and tremendous navigational skills. “Stay where you are” is only easy when you have the help of gravity, and it’s alwsys an illusion. At no point do you ever stay where you are.
No I’m not. Wells’ time machine is never “free of time and space”. It was built and then remains in place (more or less) for hundreds of millenia. In the book the traveller describes watching the world around him change rapidly as the machine accelerates through time. It doesn’t disappear and reappear like the TARDIS.
Of course I realise the planet is moving. The Time Machine is also moving, and in such a way that it retains its exact relative position to the planet. Amazingly it does this without any means of propulsion, relying instead on contact forces (weight, friction) generated by the gravitational attraction between the Machine and the planet.
Seriously, the point is that the Time Machine does not leave our space-time and appear in another. It simply exists through time, like a building or a rock or a pyramid. It is a four dimensional object where the Traveller can move along one of its dimensions.
Anyway, enough arguing about a fictional (and probably impossible) machine. Read the introduction to The Time Machine if you are interested in how H. G. Wells explained it:
http://www.gutenberg.org/ebooks/35
This was a very succinct explanation that I have tried to explain to people many times myself. There is no universal point of reference, and thus no way to map where in time the earth was when you want to go. That's not to say there may not be an answer to that problem, but merely that the problem exists.
If you could see all of time outside of the 4th dimension, you might be able to place yourself where you want to be.
From a narrative point of view, the spatial problem as stated is a quite decent post hoc argument for why time travel is usually fraught with danger, even after the science is known, as predicting the exact parameters needed would be nigh impossible.
One could easily argue that big whiteboards laden to the brim with integrals and capital sigma (summation) rich equations indicate a data rich problem rather than a theory heavy one, and that the inevitable squashed, disappeared, or exploded melon fits very well into this framework.
Shooting a water melon at several million miles per hour so it hits a small time travel device correctly in all N>3 dimensions is obviously going to make a royal mess quite a few times, as evidenced in many movies!
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[ 31.1 ms ] story [ 689 ms ] threadFrame dragging is a good answer. You are locked to the inertial reference of the nearest big body (add yo mom jokes here if you like).
But I don't think frame dragging solves the problem, at least not without a complete rearrangement of relativity, in which case you don't really need frame dragging.
The problem is that frame dragging occurs in the local environment - if you're being dragged along with a frame, you're not traveling at any unusual vector through time.
Time travel necessarily deviates from the spacetime path of the frame, otherwise you'd just be traveling with the frame as normal. And if you deviate from the path of the frame, then ordinary frame dragging isn't going to help you. Of course you could perhaps invent some sort of more spooky frame dragging to handle this case, but it wouldn't have the same physical basis.
Big deal that fiction doesn't actually detail this, it adds nothing to the narrative.
It's only a communications device, not a transportation device but it does consider the movement. The signal is sent to the same point in space where the machine currently is, the range limit is how far away from that point you can be and receive it.
This might be why time travel in Terminator movies creates the sphere of energy right before the traveler appears: it clears out the space. But then why doesn't the person experience a moment of disruption being inside a perfect vacuum?
The machine no more needs to calculate its motion through space as it travels through time than a rock or an old building does.
Seriously, the point is that the Time Machine does not leave our space-time and appear in another. It simply exists through time, like a building or a rock or a pyramid. It is a four dimensional object where the Traveller can move along one of its dimensions.
Anyway, enough arguing about a fictional (and probably impossible) machine. Read the introduction to The Time Machine if you are interested in how H. G. Wells explained it: http://www.gutenberg.org/ebooks/35
If you could see all of time outside of the 4th dimension, you might be able to place yourself where you want to be.
One could easily argue that big whiteboards laden to the brim with integrals and capital sigma (summation) rich equations indicate a data rich problem rather than a theory heavy one, and that the inevitable squashed, disappeared, or exploded melon fits very well into this framework.
Shooting a water melon at several million miles per hour so it hits a small time travel device correctly in all N>3 dimensions is obviously going to make a royal mess quite a few times, as evidenced in many movies!