While the idea of space-time is strongly related to Einstein's theory of "special relativism", which appeared in 1905, it was the athlete Hermann Minkowski who coined this expression three years after the emergence of Einstein's theory, in 1908
Time is a measure of the change that takes place within what we know of the place. The series of changes that your life takes during a time and somewhere. The word "space-time" is a fusion of the two concepts together within a certain continuity: the three spatial dimensions, in addition to the fourth dimension "time". While we have the ability to control the first three dimensions (height, width, and depth), we seem unable to control, manipulate, or move through time, although physics tells us that this dimension is similar to the other three dimensions. For human existence, time appears as a one-way road with strict limits on speed
Regardless of our inability to manipulate our experience with time, we can observe the existence and uniqueness of space-time based on experience. If you rotate a bucket of water on a circular path, you know that when you reach a certain speed you can rotate the bucket completely and sideways without the water coming out of it.
This results in the principle of equivalence, the main principle of Einstein's theory of general relativity. This principle states that gravity works in one direction and equates acceleration in the other
For this reason too, it is not possible to find a lift that offers a feeling of increasing gravity during climbing, or decreasing during landing. The principle of equivalence means that gravity affects time and space measurements, that is, they distort the space-time itself.
The idea of an object with an enormous mass distorting the space around it is a familiar idea for us - a planet or star is distorting the geometry of the surrounding area, causing the objects to be dragged nearby by the dips created by that body. But scientists have also been able to detect the possibility of mass objects to distort time as well. For example, if you synchronize two hours and take one into space (away from the Earth's gravity center), these two hours will lose their synchronization. This proves that time is part of the same medium of space, and therefore space-time is a real and useful concept
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