The Research

We all travel in time. During the last year Ive moved forward one year and so have you. Another way to say that is that we travel in time at the rate of 1 hour per hour.We like the idea of time traveling because if we go back in time many of us would like to change things to make the future better. And if you travel to the future youd want to come back with some wonderful discovery and share it to improve human life. So the desire to time travel is quite a positive fantasy to have But the question is can we travel in time faster or slower than 1 hour per hour? Or can we actually travel backward in time going back say 2 hours per hour or 10 or 100 years per hour?It is mind-boggling to think about time travel. What if you went back in time and prevented your father and mother from the meeting? You would prevent yourself from ever having been born! But then if you hadnt been born you could not have gone back in time to prevent them from the meeting.The great 20th-century scientist Albert Einstein developed a theory called Special Relativity. The ideas of Special Relativity are very hard to imagine because they arent about what we experience in everyday life but scientists have confirmed them. This theory says that space and time are really aspects of the same thing-space-time. Theres a speed limit of 300000 kilometers per second (or 186000 miles per second) for anything that travels through space-time and light always travels the speed limit through empty space.Special Relativity also says that a surprising thing happens when you move through space-time especially when your speed relative to other objects is close to the speed of light. Time goes slower for you than for the people you left behind. You wont notice this effect until you return to those stationary people.Say you were 15 years old when you left Earth in a spacecraft traveling at about 99.5% of the speed of light (which is much faster than we can achieve now) and celebrated only five birthdays during your space voyage. When you get home at the age of 20 you would find that all your classmates were 65 years old retired and enjoying their grandchildren! Because time passed more slowly for you you will have experienced only five years of life while your classmates will have experienced a full 50 years.So if your journey began in 2003 it would have taken you only 5 years to travel to the year 2053 whereas it would have taken all of your friends 50 years. In a sense this means you have been time traveling. This is a way of going to the future at a rate faster than 1 hour per hour.Time travel of a sort also occurs for objects in gravitational fields. Einstein had another remarkable theory called General Relativity which predicts that time passes more slowly for objects in gravitational fields (like here on Earth) than for objects far from such fields. So there are all kinds of space and time distortions near black holes where the gravity can be very intense.In the past few years some scientists have used those distortions in space-time to think of possible ways time machines could work. Some like the idea of wormholes which may be shortcuts through space-time. This and other ideas are wonderfully interesting but we dont know at this point whether they are possible for real objects. Still the ideas are based on good solid science. In all time travel theories allowed by real science there is no way a traveler can go back in time to before the time machine was built.