Let's try to be simple..

(If I do go wrong anywhere, PLEASE correct me.. )

Now there two main problems in the "Classical" big bang theory..

One of them is the flatness problem.

Now, we know space-time is extremely flat from Einstiens predictions and have proved that with our "Sensors" etc.

Now the issue is:

If space-time is "Extremely Flat" and the universe has "Banged" from a very dense medium, how come space-time hasn't expanded?

And now here comes the best part..

The solution is in "Chaotic Inflation" .

Now just imagine, Nothing.

Literally nothing, you can assume it's just pitch black with your mind.

And if it's pitch black, that is vacuum.

Therefore, vacuum will expand creating "Space", and we know the expansion of space can travel faster than the speed of light.

So we are literally still not creating anything, it's just.. Space.

So we are still obeying mathematics, 0 = 0 .

Now, quantum fluctuations come into play with particles appearing and disappearing all the time, (This happens all the time even now. ) and if there is less energy involved these particles can stay in our dimension or the spatial dimension for a longer period of time.

Now we have a positive value, the matter.

So we can't say 1 = 0, doesn't make sense mathematically.

But here's the catch, we know gravity is negative and is only equal to 0 at point infinity, which really doesn't exist.

So let's assume gravity at that moment is = -1

So, 1-1 = 0.
0 = 0 .
Therefore, you are not creating anything in the universe since it is cancelled, and you are just manupilating the number "Zero" .

Same thing goes with charges, every charge created in the universe will have it's opposite charge created immediately.

Therefore nothing is really happening, 0 = 0.

So therefore our space-time doesn't expand since we really didn't create anything..

Now the other issue is, the horizon problem.

Which I think I will leave it for another time, since I do not have a "Very" clear view of it..