You could say that we humans are already time travelers.Traveling on our life journey through what we perceive as time for our birth to our death. Experiencing events ans they happen day by day. But what if we could do much more than travel along this linear line that is life? What if it were possible to travel back in time, or travel far into the future to see what life will be life?
We go back in time when we recall our past and to the future when we imagine and anticipate what to come in our life. We capture past events on film (video and still images) and in writing. We take ourselves back in time when we read the books and watch TV shows on our history. Astronomers looking at the stars are actually looking into the past of our universe. The further away from the earth the look the further back in time they look.
It was Einstein who first introduced the world to the notion that time travel may be possible when he came up with his General Theory of Relativity. In this he treats space and time as one, four dimensional object. He called this space time. In his theory he states that time is not absolute and flows differently for different observers. (Time does not flow when the universe is viewed as a whole. In essence it is timeless.)
You could say that planes and other fast moving vehicles are time machines.
When you travel on an aeroplane you cross time zones hence you travel in time but this does not make the plane a time machine. When using relativity to explain the effects of traveling on a plane we can then show that they could be time machines.
In his Special Theory of Relativity Einstein states that an outside observer would see a clock on a moving object tick slower than one that is at rest next to him.
The above statement is a great starting point in my quest to prove time travel to be possible as it shows that if it is right, time would travel slower inside a fast moving vehicle than it does outside of it.
If we were to test this theory we would need two identical accurate time keepers, a fast moving vehicle i.e a jet and two observers to keep the clocks safe. Both clocks are checked and set to the same time. One observer boards the Jet with one clock and the other observer stays on the ground with the other. Send the plane off on a long round trip. When the plane lands compare the clocks. The clock that was on the plane should be slower than the one that was left on the ground.
When you read further into this part of The Theory of Relativity, the loss of time on the plane should only occur when the plane is traveling eastward. The clock should gain time on a westward journey. This is to do with the earths rotation and gravitational forces.
Thanks to J.L.Hafele and R.E.Keating who did a series of experiments in 1971 we have no need to find the equipment to do the above experiment ourselves.
They took four Cesium atomic beam clocks and placed them on commercial jet flights around the world, first eastward, then westward. They used clocks at the U.S Naval Observatory as their ground reference clocks.
Using the planes flight plans and The Theory of Relativity Hafele and Keating predicted that the clocks on the planes should have lost 40+/-23 nanoseconds during the eastward trip and gained 275+/-21 nanoseconds during the westward trip. In actual fact when the clocks were checked they had lost 59+/-10 nanoseconds on the eastward trip and gained 273+/-7 nanoseconds on the westward trip.
They proved that time does seem to flow differently in a fast moving vehicle than when we are at relative rest. It to some scientists also shows that if we traveled at the right speeds we could travel backward or forward in time whenever we wanted to.
The faster you travel the further forward or backward in time you would travel. So if we could travel at the speed of light we could in theory travel a great distance into the future.
So using Einstein’s Theories of Relativity you could say that traveling to a distant point in the future is possible. The only problem with the Relativity based theory is that it does not allow for backwards time travel. This means that yes you could go forward but you could not get back to your own time.
So yes time travel might really be possible.
