After a discussion about time travel, I asked my high school science teacher, “How can we be sure time even exists? How do we know it’s a tangible thing that can be traveled through?” His simple reply was to say that time can be measured. Therefore, it exists. That answer was never enough. As I’ve grown older, I still believe that time doesn’t exist, because all it is, is a term used to describe the interaction between matter. As matter interacts, the physical world changes, thereby creating one’s perception of ‘time’. The more gravity one has, the slower matter interacts and the inverse. One can’t go back in time, because one can’t rewind all the infinite physical changes that have taken place. However, one can speed up the interactions. So, I pose you the same question. How can we be sure time exists?