The reach of our (human race and civilizations) sensors were very limited in the large distances and in the miniature scales - in astronomy and in microscopic scales.
We did not discover the outer space, the deep oceans floors, the bacteria, the molecules until recent years - recent w.r.t. the light years in "big bang" scale.
That's why I used flat earth - and use calculate as in "miscalculated" to explain my point.
I challenge anyone to show me the numbers and calculations to back up any theory!
"big bang" was a theory based on very complex calculations published for peer review.
However, it remains a theory because there is no way to prove it or even validate it.
BTW - only mathematics and logic can be proven - not science.
I am a scientist, an engineer as well as someone who have analyzed and applied mathematics and logic in real world computer applications, so, I welcome any debate based on facts and calculations, mathematics and or logic.