And what he said was nonsense; 10 LY/s is faster than light; you must be a hypothetical particle with some crazy properties and our math really breaks down at t

And what he said was nonsense; 10 LY/s is faster than light; you must be a hypothetical particle with some crazy properties and our math really breaks down at that point. In space you need to think in terms of relative velocities less than c and acceleration. To get a reasonable sense of how far away Andromeda is consider how long it will take to get there, which is just a few years.