Question: Do we have the potential to travel at the speed of light? Will time really slow down if we do?

Arttu Rajantie answered on 14 Jun 2011:

Nothing (except massless particles like photons) can travel at the speed of light, but in principle we could get very close. Then time would really slow down, in the sense that we could travel to Alpha Centauri and back in what would feel to us as just an instant, but when we get back to the Earth our friends would be eight years older.