What prevents scientists from being able model what was before the Big Bang?

Question

What prevents scientists from being able model what was before the Big Bang?

In: 822

Answer 1

We used to think the universe oscillated between expansion and collapse.

Then we made some measurements of cosmic background radiation that seemed inconsistent with that theory, so we thought there was just the one big bang and the universe would keep expanding until all energy reached its lowest level in the heat death of the universe.

Recently there have been some revisions in string theory that again open the possibility that the universe follows an oscillatory model, in which case there could have been any number of big bang / big crunches before the one we know and love.

https://www.space.com/what-came-before-big-bang.html

The truth is we don’t know the answer and need more data.