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Could one theoretically use the expansion of the universe to travel through it? At least In one direction?

That’s it that’s my question. I’m not a physicist but I do get ideas. I also wonder if one could theoretically ride the magnetic fields in the universe and if space is like water could it be possible to “slap it and ride the wave”?

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The expansion of the universe is happening in all points in our surroundings, all three dimensions at a time. All points in three dimensional space were at the beginning of the universe's one point ( classically, ignoring quantum mechanics) in the beginning of time.

Think of the surface of an expanding balloon, where all points are going away from each other, an ant on the surface would see no specific direction of expansion in its two dimensional universe on the surface. It would be traveling whether it wanted to or not.The expansion on the balloon is not "going" anyplace, for the ant to use it as a transport mechanism. It is more complicated in the four dimensional space time but similar.

There are forces that keep the atoms and molecules and planetary systems from expanding with the space time expansion, but that is another story.

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  • $\begingroup$ I think this answer covers it. You can't travel in one direction because the expansion is happening in all directions. $\endgroup$ – Jay May 11 at 3:41
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  1. Yes, you are traveling the universe right now due to it's expansion, at a relative speed of 67.4 km/s per megaparsec, which is quite fast. Unfortunately there is no easy way you can change direction or speed, so you can just enjoy the ride.

  2. You can utilize magnetic fields to change your speed, but magnetic fields found in interstellar space are not strong enough to be of much use. Magnetic fields are currently used to slowly rotate satellites (or more precisely to unload control moment gyroscopes).

  3. "Slap and ride" is not feasible. There is nothing you can easily slap. Space is just too empty. Yes, even in empty space there is dark matter, neutrinos - but they don't like to interact with anything.

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