"Why time travel is impossible"
For there to be time travel, there has to a 'current future'. A little proof? You don't see anybody walking around in the present from the future now do you?.
If time travel were possible, you would see people from the future in the here and now.
Time travel to the future is possible, sort of. Traveling faster than the speed of light places you in a future with people from the present, but no "future" as in 1000 years from now. Nothing exists in the future because it's not happened yet.
So now then, no current future = no time travel. So what does exist in the future? Nothing but time,darkness and a sprinkling of present. Future time travel exists only for the time traveler.
I've been studying this subject for years, most fascinating indeed.
The simplest solution tends to be the best one, but sometimes the simplest explanation isn't always clear.