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A comment on The horizon problem for faster than light travel. Parent comment

Re:The horizon problem for faster than light travel by mulmen on Thursday January 20, 2022 @08:14PM (#30017891)
Only for sufficiently small values of anywhere. Even near-light-speed communication in fiber optics has detectable and significant delay just in crossing a continent. A trip made physically by humans every day.

Near-light-speed travel to the Moon would take a few seconds. Near-light-speed travel to Mars would take longer than my drive to the grocery store. These are not "instantaneously."

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Re:The horizon problem for faster than light travel by teaearlgraycold on Thursday January 20, 2022 @08:44PM (#30018130)
I'm talking about time dilation. From the perspective of the pilot of a near light speed ship a trip across the galaxy would be instantaneous.
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Re:The horizon problem for faster than light travel by psyc on Thursday January 20, 2022 @08:56PM (#30018230)
It's instantaneous at 100% of light speed (impossible for massive objects). At "near" light speed, you need seventeen nines (0.99999999999999999c) to bring a trip across the galaxy down to a subjective day. I'm not sure how near your idea of "near" is. You also need instantaneous acceleration at both ends, which is quite a requirement.
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Re:The horizon problem for faster than light travel by krapp on Thursday January 20, 2022 @08:42PM (#30018123)
OK. Only Pluto in a few hours, Mars in a few minutes, and the moon in less time it would take for me to reach the toilet from my living room.

Not literally instantaneous, but still practically instantaneous at the scale of the solar system.

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