A review of the concept of synchronicity

Einstein rightly thought with unparalleled depth on the concept of Synchronicity 2. And he began by asking about the way in which we define an event in physics, when I say that I will meet you at such-and-such place at such-and-such hour, this means that I identify a point from the place and a moment in time: the event needs four numbers to fully define it, three numbers that determine its coordinates Spatial number and determines its temporal coordinate. But how do we define the spatial coordinates?

Einstein said that it can be determined by imagining an infinite network of orthogonal rulers to which we can locate any point in space. Then he said that to determine the time of an event, we can follow two methods: The first way is to put a clock in the principle of a set of coordinates and wait for the light coming from the event, then when we take into account the time that the light needs to reach us, we can determine the time coordinate of the event. There is another simpler way than the previous one, which is to put a clock in the location of the event and take the reading of the clock at the moment of this event, as Einstein said that when we talk about the time of an event, we are talking about two events that happen together or what is called two simultaneous events.

He gave an example that when we say that the train arrived at the station at seven o'clock, this means that the two events of the train’s arrival at the station coincide with the fact that my clock hands apply to the reading that gives the seventh hour. But here we will have a new problem: If we say that we will put a clock at each point of this grid of rulers, and this clock will determine the time of the event, then we do not guarantee that all the clocks read the same reading or that they are running at the same rate. So how can we compare two different clock readings?