Here is a popular argument lately:
– there is one possible world where we are real humans with intelligence
– there are many many where we are simulated beings in some advanced civilization's AI.
– therefore it is probable that the "we are real!" feeling is just a simulation. Far more likely, counting the possibilities, that we are simulations not real
That's the Simulation Argument and it comes with a formula.
https://en.m.wikipedia.org/wiki/Nick_Bostrom <– will get you there.
I think it is wrong.
Mainly because the probability bit of it was already true. There are many many possible worlds where malevolent demon scenarios are why we feel we are real. Also dreams (all the dreams of all the people in all the nights of time, and dreams within dreams). And other forms of anti-reality.
But computer simulations add to this. So are there more?
That depends on whether many infinities are more than some infinities. Which is about Cantor Countability.
So simulations mean it is less probable that we are really in the real world.