Your premise is flawed - it is possible to time travel - and more then 1 way to do so, and there are no laws prohibiting time travel.
The ways in which one can time travel include:
- As a person aging on the face of the earth.
- By travelling very fast - and people do do this (eg people on the ISS)
- By travelling between timezones (NZ to LA is a very good example - 20 20 hourhour time difference but only 8 hour travel time, crossing a date line)