Introduction
Scientific revolutions, almost by definition, defy common sense.
If all our common-sense notions about the universe were correct, the science would have solved the secrets of the universe thousands of years ago. The purpose of science is to peal back the layer of the appearance of objets to reveal their underlying nature. In fact, if appearance and essence were the same thing, there would be no need for science.
Perhaps the most deeply entrenched common-sense notion about our world is that it is three dimensional. It goes without saying that length, width, and breadth suffice to describe all objects in our visible universe. Experiments with babies and animals have shown that we are born with an innate sense that our world is three dimensional. But to record all events in the universe, we need another dimension. If we include time as another dimension, then four dimensions are sufficient. No matter where our instruments have probed, from deep within the atom to the farthest reaches of the galactic cluster, we have only found evidence for these four dimensions.
Time is a very complex dimension. So not only in science, thus also in common usage, time is hard to understand. There are so many possible meanings implied.
If you just say the word time when you enter different situations, it depends on which room you have entered. When you enter a restaurant, you will receive the time of the time zone you are right now, which is the usual answer. But there are many different answers possible. Like if you enter a soccer stadion. Everybody will yell at you the score, how much time there is left, and to shut up. If you sit in a plane, and you ask the captain will tell you several times you haven't even thought of: The time of your arrival and departure in the time zone you left and will arrive, how long your flight was since now and how long it will take in miles per hour or km per second. Which speed the plain in that moment has, and which average speed it needs for take off or landing. If you enter a fast-food restaurant and you just ask "time?", you will hear how long it takes to finish the fries or the burger. If you are in a university and you ask for "time?", the answer depends again in what room you are. In the dorms you will get a tired "too late" or a curse like "damn it! I'm late." as answer. On the foodcourt a hectically "just five more minutes" is the usual answer. And during a physics class, the answer is a long precise definition of time.
What time really is, nobody truly can tell, but scientists try their hardest to find answers to their unanswered questions. In this Special Topic "Time" I would like to give an idea of the momentary situation science is now, and show some possible answers from some of the brightest minds of mankind.
But also scientists do not agree in every respect. They try to fit all their observations in formulas they again try to combine all to get a unifying theory about the smallest and the largest things in our universe we live in.
The aim of science is to penetrate into smaller and bigger dimensions and not to stop until humankind has a complete theory of all forces and particles that appear in nature.
Like Thomas H. Huxley once said, The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of an illimitable ocean of inexpl- icability. Our business in every generation is to reclaim a little more land.
On the next pages I would like to give an easy understandable, brief description of what time is considered to be and want to try to uncover some secrets of Time