

Cosmologists Prove Negative Mass Can Exist In Our Universe - sigil
https://medium.com/the-physics-arxiv-blog/250a980320a7?source=tw-1b09627ba6f7-1405535324452

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sp332
Can we have an Alcubierre drive yet?

One of the things that worries me about negative mass is how it responds to
force. If you poke a negative mass object, won't it move in the direction of
your finger? Wouldn't that make an even stronger force (since the object is
moving _toward_ the force)? Is there a limit to this or would a positive-mass
object and a negative-mass object be permanently attracted to each other until
something breaks at a fundamental level?

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TheLoneWolfling
A related interesting drive:

Take a ferromagnetic negative-mass object of the same mass as your spaceship.
Suspend it within your spaceship with electromagnets around it. To accelerate
forward, try to pull the negative-mass object _backwards_ , and vice versa.
You can do the same thing if it has an innate magnetic field, or with
electrostatics. (You can also do the same thing with gravity, but your
acceleration will be annoyingly small)

Voila, a quote-unquote reactionless drive! (It isn't actually, the net
momentum/kinetic energy of the system does not change)

But yes, there are a number of problems associated with negative mass.

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sigil
Here's the paper, "Negative mass bubbles in de Sitter space-time" \--
[http://arxiv.org/pdf/1407.1457v1.pdf](http://arxiv.org/pdf/1407.1457v1.pdf)

