Yeah it's been a while.
It seems like I slightly misunderstood your position.
There are a number of problems with a metaphysical infinite regress. One being that there are no reference points in an infinite regress. Here, infinity refers to length (infinite length of time/infiniate amount of causes) yet two things can't actually be an infinite length of time apart. There will always be a finite number for the distance they are apart, there isn't a point where it goes from a finite number (eg. 9 billion trillion light years) to infinity.
Sounds good so far. I noticed that you are imposing a beginning on the Universe. To measure infinity between Point A in time and Point B would be to draw a line from Point A to an infinity in either direction. Point B can never happen because it has no place. The problem with this is that Point B is then a Beginning or an End to the timeline, which is forbidden in infinite regress. It's like showing someone an orange and asking them "where is the vine?" (You already said this, but I am just restating it.) On to your reason for making a beginning.
So, I understand that you are setting a beginning because all of the events in time require a prior event, which would eventually lead to a simple beginning that required no prior event.
BUT, and this is where I make my argument, this first event does not have to be responsible for everything that came afterward. Maybe every instance, including it, is just the result of a rule repeated. In other words, maybe the universe just follows laws, and it is a result of plugging a time value into the equation of the law that gives result#5; result #4 did come before result#5, but it didn't actually
cause it from this point of view.
For example, take a function. We'll use y=x+1 and start at x=0 for clarity, where x is time and y is a value dependent on the value of x.
Simply because x=0 yields 1 does not mean that every value that comes afterward is the result of y being 1. They are all, y=1 included, representations of the function y=x+1 ! You have a shape with each value adhering to a pattern.
The first cause wasn't a necessary cause. The only necessary thing was the equation itself.
Taking this a bit further...
It's possible that the universe is like a gigantic static block (time inclusive) that just exists on its own. Just like an description you made for the existence of a self-necessary, static being some time before, but brought down a tier so that the universe is a solid, unchanging block rather than the god. Time would be along one dimension and the other three (or more if there are) would have their own axes. We can assign variables to all of these dimensions, but all of them would finally rely on just one variable, x. So t= x^2, p=x-3, g=some other operation with x, c=something else done to x. There is no time necessary on this level, though. You have your set of equations (your shape) and every value for them exists at that instant. Again, all you need is to establish that your equations exist. At some point, all these equations (laws) could just be different implementations of a single law, which by itself exists.
Anyway, with the idea that the first cause/event/object existing inside the universe is the reason for all later existence out of the way, we can safely build our infinitely regressing timeline.
Here are some more examples of the idea just in case (Arrows indicate causation.):
(ex: You kick a ball, and it flies forward. This argument is the difference between interpreting it as (1) your kick caused the ball to go forward and (2) the laws overlapped in such a way that your leg is next to the ball at t=1, hitting it at t=2, and the ball is in the air at t=3.)
(ex2: A>B>C>D>E>F>G [Timeline is independent. The t value does not affect the letter, only the letter before it does]
vs
TIME 1,2,3,4,5,6,7
_____v v v v v v v
Place A,B,C,D,E,F,G)
Also , if X asks Y how many years have passed, Y says 'an infinite amount'. Ten years later, if X asks the same question, if Y says 'an infinite amount' he's not accounting for the ten year difference, you can't actually tell ten years have passed. However, he can't say 'infinity plus ten years' because infinity isn't a number applicable in mathematical equations.
For example, if the present equals 0, you can't regress back until you reach infinity. This goes back to my first point, it will always be a finite number.
First paragraph above.
Argument summary:
You are right that a beginning (the absolute time 0) is incompatible with infinite regress. The only reason for trying to reach back to infinity is to get to a beginning, which your argument for a first cause justifies as a necessity. The argument says that everything requires a cause except for the first cause, which is existence itself.
But here's why that is unnecessary.
Maybe you can build a universe where our 'first cause' is not actually the reason for the later developments. It is just a point among the others and happens to be where x=0.
So then we just decide to make a universe that runs according to this, with time 0 (x=0) being an arbitrary time point. It doesn't matter. What matters is that every event in that infinite timeline is a result of the laws of the universe, the equation/pattern, and not the state of the value before it.
As a side note these laws could just be specific instances of a super law. Whether or not it is mandatory they would exist in that form or are chosen by random for each universe doesn't matter.
What do you think?
I personally see it is a cool idea but at the very best it is just in the realm of possibility.
Nothing more, possibly less.