What Does Science Tell Us About What Was Here Before the Big Bang?

Time travel into the future is 'absolutely possible' according to edge cosmology. We go into the future at different rates depending on how we move around relative to each other. You could experience, let's say, your experience one year on your spaceship and come back a year older. But if you've gone into the future and you return, aren't you then going into the past from the future? Isn't that the premise of time travel? If so, i have one in my head because i know the structure of space and time as we understand it,. but it does not prevent you all, from getting into the future or anything like that.