[marcusverus]

As long as we're being pedantic, the trip is only instantaneous if you're able to instantly accelerate to c. Otherwise, it would take around two years for the occupant (one year to accelerate to c upon departure and another to decelerate on arrival), assuming acceleration at 1G.

[AnimalMuppet]

Ahem. To add yet more pedantry, one year of acceleration at 1G doesn't get you to c, but only fairly close. (I worked that problem nearly 40 years ago, so my memory of "how close" is a bit obscure.)