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hwillis
on Dec 31, 2016
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Uncertain Propulsion Breakthroughs?
If it can accelerate forever, thats proof enough for everyone. However violating the conservation of momentum is a Big Deal. Mathematically that shouldn't be possible due to Noether's. The bar to proof is therefore very high.
naasking
on Dec 31, 2016
[–]
General relativity doesn't conserve energy in some spacetimes, so it's not unheard of.
andrewflnr
on Dec 31, 2016
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I'm fairly certain GR conserves momentum, even if it doesn't conserve energy.
naasking
on Dec 31, 2016
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I thought so too until recently, but in GR energy and momentum are unified in an energy-momentum metric which is only
locally
conserved [1].
[1]
https://en.wikipedia.org/wiki/Physical_theories_modified_by_...
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