Warp Drive

Closed Timelike Curve(CTC) is a path that violates causlaity.

This is true on General Relativity, but it looks not natural.

One reason of that is we need negative mass to make CTC.

But in GR, negative mass is not problem.

There is quantum interpretation of CTC.

And in QFT, negative mass looks possible at first, but Energy Contidion block that.

(For weak condition, there exist bound of negative energy, and existence of CTC need high density of negative mass.)

But someone says they found negative mass!?

(No just experiment of Casimir effect of sertain wall. We just need to understand vaccum first.)

If we can make negative mass, it is not useful.

Kinks, energy conditions and closed timelike curves

Negative energy densities in quantum field theory with a background potential

However, maybe we don't need negative mass!

Interesting paper is two:

Positive energy warp drive from hidden geometric structures

Desiato and Storti (2003) ?...

Breaking the Warp Barrier: Hyper-Fast Solitons in Einstein-Maxwell-Plasma Theory(danger)

However, it blocked again.

Generic warp drives violate the null energy condition

Um... there is huge mountain.

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