[brandonhorst]

That's not how that works. Traveling 100 light years will take >100 years for the folks on the ship no matter how fast it's going.

[ncmncm]

It is amazing to find pockets where General Relativity has not penetrated at all.

It will certainly take >100 years for the people left behind. On board it could take time anywhere between infinity and zero. Too long, though, and they wouldn't go.

[arrow7000]

That's not true. If you travel close enough to the speed of light time dilation becomes so extreme that it may only take a few subjective years for the travelers to travel 100ly.

[matt-attack]

As your ship approaches c the distance to your destination gets physically shorter due to length contraction.