Quotes

Time travel is no longer regarded as strictly science fiction. Einstein's theories of general and special relativity can be used to actually prove that time travel is possible. Government research experiments have yielded experimental data that conclusively illustrate that fast moving aircraft have traveled into the future. This phenomenon is due to the principal of time dilation, which states that bodies moving at high velocities experience a time that ticks slower than the time measured at zero velocity. Phenomena known as wormholes and closed timelike curves are possible means of time travel into the future and the past. Traveling into the past is a task which is much more difficult than traveling into the future. This feat has not yet been accomplished -to our knowledge- and its theory involves complicated scenarios of tears in four dimensional space-time, and traveling near the speed of light.  Obstacles which prevent our attempts to cheat time include our inability to move even close to the speed of light, and finding a source of energy as powerful as an exploding star. Simply because the proposal of time travel is backed by scientific theory, is no reason to expect that it is easily achievable. Numerous arguments are proposed that prevent time travel into the past. Both common sense and scientific fact can be used to paint scenarios that become serious obstacles.

Imagine if you will, that you are one of the people sill alive today that was born prior to 1903, when the first airplane took flight. When you were young the idea of flying would probably have been quite exciting. Some scientists believe that we may presently be living through an identical scenario. Leading scientists believe that our children will live to once again see the impossible become routine. This will require the development of spacecraft that can travel at speeds on the order of two hundred million meters per second, that's about four hundred and fifty million miles per hour. Craft traveling at this speed will take us near the speed of light, where time actually slows down.

This is what's known as time dilation. Einstein's theories predict that the faster a spacecraft moves, the slower time appears to change inside of it. Imagine that a rocket ship takes off from earth and approaches the speed of light. If we were to watch it from earth with a very powerful telescope as it traveled away from us, we would see everyone inside the ship as being frozen in time. To us their time would slow down, but to them nothing would change! This has been measured in the laboratory and on location using atomic clocks, aircraft, satellites and rockets. It is proven that time slows down with respect to rest frame the faster you move. In 1975 Professor Carol Allie of the University of Maryland tested Einstein's theory using two synchronized atomic clocks. One clock was loaded on a plane and flown for several hours, while the other clock remained on the ground at the air base. Upon return, the clock on board the plane was found to be ever so slightly slower that the one on the ground. This was not due to experimental error, and has been repeated numerous times with the same result. This difference in time is even more pronounced in satellites such as the space station. This is because these objects are traveling at speeds much faster and for much longer periods than possible in an airplane.