It’s really a matter of time...
Isn't it? or is it?
Imagine a situation where you can move 100 times as fast as anything imaginable... would you be able to walk right into future? theoretical, maybe! because you have moved ahead of everyone, everything... but it’s a li'il hard to imagine.. but imagine a time when what takes 24 hours for the rest of everything you know, can be done in, say, 10 hours by you...A controlled increase in speed should take you to a "relative" future state...
Also if you are able to slow down... like reeeeeeeeeally reeeeeeeeeeally slow down, would you not be able to move back into the past? because the rest of the world has moved ahead! and so has the trees, and the earth, and the snow and everything else too... going by the same example... 24 hours for the rest of the existence would mean, umm let's say, 36 for you...and a controlled reduction in speed should take you to a "relative" past.
if you can switch between the fast and slow at your own sweet will, you will be able to time travel!
This of-course depends heavily on what you consider a constant... because present, past and future are only relative terms... tomorrows' past is today, but today is also yesterday's future... so be a li'il careful with choosing your reference marks! also if the reference moves around then the entire calculation of the past, present and future can go for a toss, and you will land up in a totally parallel world! How about that!
I really wish I was able to pictorially or visually represent what I am writing right now! damn it!