My conception of the Big Bang is that out of nothingness – no time, no space, just an infinitesimally small, quasi-dimensional speck that contained everything needed to form the universe as it is today – instantaneously exploded and expanded in a blink of the eye or the snap of the finger. Whatever size it obtained in that instant is anyone's guess.
I wonder if it may not have happened so fast, so instantaneously. The current theory is that the universe is not only expanding, but accelerating, so why can't it be that at some point the universe was not expanding so fast, but quite slowly, relative to our current time frame?
Damn. Time is such a tricky little dimension. I vaguely remember reading an article about when exactly our three spatial dimensions and time were created, relative to the Big Bang, but I can't even remember the gist of it. It might be my imagination, but I also vaguely remember reading an article stating that time, at some point in the past, moved at a different speed, but I forget if it was faster or slower. How do you even measure that?
Perceiving our three dimensions is easy, look up, look down, look right, left, forward, do the hokey-pokey and turn yourself around. Perceiving time going by may take a little concentration, but yes, there it is going by, and I suppose it is going by at a certain rate. But if time suddenly sped up or slowed down, how would we even notice it? I think that was covered in the article, so I'm pretty sure it wasn't my imagination.
So maybe the Big Bang at the time it occurred was observably slow, no less violent and dramatic, but time-wise – slow. Strange, since I think we equate a violent occurrence with speed or rapidity.
It's uncanny how well Buddhism and modern Cosmology go well together. Not specifics, but basic things. For example, a component of enlightenment is an understanding or realization of moments in time, what a moment is, how it arises, exists, changes, and decays.
Also, the Buddha spoke in inconceivably large numbers, such as numbers as great as the grains of sand that line the holy river Ganges. Or if each grain of sand along the holy river Ganges was a Ganges itself, and numbers as great as all the grains of sand of all of those rivers Ganges.
I heard an astronomer state that there are more stars in the universe than there are grains of sand on the planet earth. Take a handful of sand and watch it filter through your fingers and it's mind-boggling how many stars there are in the universe.
There are a bunch of things, through the years, that while reading some Buddhist tract, I'd equate it to some astronomical/cosmological concept, and vice versa. I like it even better when I think of the dichotomy of the Buddha coming to these realizations with just insight, and modern astronomy coming to them with a bevy of scientific instruments and observations. The two extremes just fitting so well together.