SimplyCurious

Perhaps I worded it badly but I already knew time was an abstract concept that was different from the system we set clocks to. What I'm asking is how physcists somehow use this abstract concept that cannot be altered with by any man-made methods to expand our kowledge of physics. I mean, time has no inherent mathematical value to it, (so far as I know) so I don't understand how anyond can incorporate it into a system with something measurable like space. Actually, under that definition of time, wouldn't that make the idea of time dilation a misnomer? If time is an abstract concept then wouldn't the time difference between two objects moving relative to one another be due to a difference in the rate of movement of the very molecules of the two objects with time not actually playing factor into it?

For years I have been plagued by an inability to understand the concept of space-time. Specifically I was never able to understand the logic behind the concept itself. I am not an expert but my understanding of space is that it is the area in which matter exists. Time is the immaterial progression of existence and we measure time using a system centered around the Earth's orbit around the Sun. (If my understanding is wrong please provide the correct answer below). From what I understand, space-time is considered to be the continuum upon which the universe exists. (Again if I am wrong please inform me). What I do not understand is how Einstein and other physicists are able to use time, an immaterial measurement found by charting movement of stellar bodies, as a component in their theories. I just do not understand how a concept like time can be joined with a physical and measurable substance like space to form the idea of space-time. I would prefer the answers to use as many layman terms as possible because I have always had trouble understanding mathematical terms.