Going with the idea that as you move faster through space, you slow down through time, while also the time dilation starts to show extreme differences real close to the speed of light, while it is actually you who's personal time is changing, from your perspective, everything else is moving faster and faster. So thinking from the point of view of what appears to be happening to everyone else, when you actually reach the speed of light, which is impossible because it requires an infinite amount of energy, from your point of view, it would seem that everyone else's personal time is moving at an infinite rate of speed. The only way that could happen is if you were no longer moving through time and you were paused at that moment. But if you are no longer moving through time, then all of your movement through the space-time continuum would then be diverted entirely to moving through space. But if you were only moving through space and not time, you'd be teleporting. You'd be moving instantly. But light moves at the speed of light and doesn't move instantly which is where I get confused. What kind of time dilation do photons undergo? In that case, it seems that even when you do reach the speed of light, you should still be moving forwards in time. But then at what speed do you have to move in order to not be moving through time? It would seem that you need to move at an infinite rate of speed to not be moving through time... an infinite rate of speed basically being the definition of not moving through time xD But then why does it take infinite energy only to move at the speed of light?
So many questions, so few answers. I hope I was still adding to the conversation but these are the points that I always get stuck on so I wanted to throw them out there.
Just about every question here is answered by this:
So then, if I were to go 99%c, and travel 1 light year, how long would it feel like I was traveling?
If you traveled for a distance of one light year at 99% c, it would take you just under 369 days (368 days 22 hours, 32 minutes, and 44 seconds) of real, non-dialated time, to travel it. Slightly under four days more than a year. But for your own reference frame it'll feel like it was only 52 days (52 days 1 hour, 5 minutes, 14 seconds). Certainly not no time. But significantly less than a year.
The threshold where it would seem that a full year takes place in the amount of time it takes to go one light year is about 70.7% of the speed of light. Exactly the square root of one half. Extremely close to exactly 211,985,280 meters per second. Slower than this, and it'll take longer than a year in your internal reference frame, faster than this, and it'll take less than a year.
But to be almost instant, you're talking considerably faster. For instance, for it to only take one day in your internal reference frame to go one light year, it'd require a velocity of 0.99999625 c, or 299,791,334 m/s, which is 1124 m/s less than c. And for it to take just an hour to go a light year it'd require 0.9999999935c, or 299,792,456 m/s -- only 2 m/s less than c. Extremely fast, but still not no-time.
For reference, the formula for amount of time passed, in years, in the moving reference frame at a given velocity
x in terms of the speed of light c after travelling a one light year of real, non-dilated distance is:
As you can see, when you are talking about instantaneous, no-time, the value would simply be zero. So for a mass-less particle traveling at the speed of light, it would not experience time at all as we understand it. Time goes on for the outside universe, but that particle itself will never "perceive" any of that.
