From relativity, how large is the time dimension?

Right now I am relearning the concepts of special relativity and learning for the first time, the concepts of general relativity. My own theories concern the lowest quanta of charge and mass in the universe but do not go into Einstein’s work. I now want to incorporate these concepts into my theory. This forum has been extremely helpful as the people here understand Einstein’s work and the related experiments to a high degree. So now I would like to know some answers and opinions about the time dimension.

What I have learned so far here is that special relativity relates to relative motion of two different objects. For the most part this involves the relative velocity and the speed of light C. Thus it tends to be a geometric type problem. General relativity relates to the effect of gravity upon an object. The stronger the gravitational field, the slower the clock will tick.

As I see it we have a present image of an object and a future image. In pure free space away from any sizable gravitational field, the present image and the future image is far apart time wise. As we increase the gravitational field, the present image and the future image gets closer together. There is a force between these images similar to the force between two electrical wires that carry current in the same direction. I believe that when we enter a black hole the present image and the future image are identical and the clock stops. In pure free space the differences are a maximum and the clock runs the fastest.

Now I would like to know what Einstein and fellow scientists specified about the time dimension.

1. How large is the time dimension time wise? (It seems to me that this dimension is tiny occupying only a few nanoseconds of time differential.)

2. What are the time quanta of steps in the time dimension (Could this be the Plank length time?)

3. If the time dimension is quantized, how many different steps exist? (Instead of a simple X, Y, Z, and T universe package, we could have a very large amount of discrete time dimensions in the package)

4. Do Einstein and company discuss a negative time dimension? (Since the past flows into the present and the present flows into the future, it is possible to look at a form of general relativity in which the gravitational field where we are presently is zero time and higher gravitational fields are negative time and lower gravitational fields are positive time. Does Einstein discuss this concept?

I look forward to your answers