Time travel is impossible because the past and future arent places therefore you cannot travel through time. You can only travel from universe to universe with the right technology. MULTIVERSE!!!
If you want to look up and learn more of this, go to google and look up quantum physics or quantum theory.
The highest mountain in the world is Mount Everest, yet the tallest mountain in the world is Mauna Kea. Highest is measured from sea level to tip, and tallest is measured from base to tip.