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Relativity is fun, but it does have some downsides. In practice, travelling near the speed of light makes you travel into the future, which is problematic.
Relativity also doesn't seem to agree with the concept of FTL travel, which is embarrassing because light is pretty slow for galactic travel.
My idea is to generate a bubble of hyperspace, in which physics misbehave in a convenient manner. The one major rule is that the speed of light in hyperspace is tweakable somehow, which is to say it will be always much higher than your speed, but also can be higher than itself in vacuum.
Of note, hyperspace will break when getting too close from a gravity well. When the hyperspace bubble collapses, you could be completely torn apart, or in a best case scenario sent wildly off-course in the galaxy next door.
My goal is to:
A) Preserve causality in all circumstances. Time travel should be excluded, although technically, if things where to go wrong, you could maybe possibly theoretically find yourself in the future on arrival.
B) Severely limit time dilation. My understanding is time dilation can't be prevented completely, but the rule of thumb should be that if time dilation makes you more than fashionably late, it's too much.
Is my hyperspace allowing that? Is there anything else I'm breaking beyond relativity?