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I still believe that black hole merger is the most efficient way. If we can create micro black hole binaries in laboratory, and let them coalesce, they can emit significant amount of gravitational wave. By tuning the trajectories properly, the amount of energy radiated via gravitational radiation can be up to 9.95% of their rest mass. Don't let them collide ...

3

Two fermions in two different points of space cannot be made to exist in the same point of space. This is a mischaracterization of the superselection rule. The idea is that a state starts out antisymmetric under exchange of identical fermions and since they are identical the state stays antisymmetric under interchange of identical fermions. So it only ...

-5

On the wikipedia page for time travel, it mentions that Robert Forward said Yes, here it is: "Physicist Robert Forward noted that a naïve application of general relativity to quantum mechanics suggests another way to build a time machine. A heavy atomic nucleus in a strong magnetic field would elongate into a cylinder, whose density and "spin" are ...

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While there are probably a lot more problems with that statements, here are a few : A Tipler cylinder is infinitely long, hence it would require the nucleus to stretch infinitely far (and due to limitations on the speed of light, for eternity) before actually qualifying as one. I am not quite sure a nucleus would even survive such a stretching. It is a ...

1

If you travel faster than light you wouldn't be going back in time from all reference frames, just some reference frames. If you were going faster than light then from some reference frames you would be traveling faster than light but still going forwards in time and from one reference frame you would be going infinitely fast while from another you would be ...

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At what rate would I be traveling back in time at twice the speed of light? What does the maths say? The issue is that you can't travel faster than light. The speed of light $c$ is the maximum speed limit. The faster you move relative to an observer, the slower you age because time passes slower. But only slower, not backwards. From pretty easy ...

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You and your friends line up. You sit down, you spend some time synchronizing your watches. And you make a plan. You measure that you are all a meter apart. And you have 299,792,458 friends. You plan out how to do a wave. You plan it so when you stand up the person next to you stands up a little later and the person next to them a little later and so on ...

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