>>16779672
> we need to assume that it was a singularity that exploded
The modern big bang model does not include a singularity. Inflation is the earliest time theory can go back to, where the universe was at a finite size and density. Nobody assumes a primordial singularity. You're debating an antiquated idea.
>>16779485
>Just because you see something now doesn't mean that the same thing was happening for billions of years
You can never prove anything in science. All there are are degrees of evidence. In the case of the hot big bang you have the most direct evidence in the form of the cosmic microwave background.
First the big bang model predicted the CMB's existence. Which was confirmed by observers. It also predicted it was a precise blackbody spectrum, unlike any known light source. Again confirmed. And most spectacularly it predicted the detailed angular fluctuations, including these peaks which originate from acrostic waves in the primordial plasma. The CMB gives a direct picture of the early universe, and it looks exactly how big bang theory predicted.
There is a reason serious alternatives to big bang cosmology all died out in the 90's. It's not enough to say "you can't prove my random assertion wrong", the burden of proof is on anyone promoting an alternative to show that it can actually fit the observations available today. Real cosmology is a quantitative science, not pulling random assertions out of your ass.