Question: how was the universe created?

Simone Sturniolo answered on 21 Jun 2013:

We know some things about the first minutes of the universe. When astronomers saw that the universe was expanding, inflating like a balloon, the idea that it could have originated in a “Big Bang”, a sort of fast explosion of matter and energy in all directions, was born. In origin, in fact, “Big Bang” was a word invented by those who mocked the theory, because they thought it was ridiculous! But now we are pretty sure that’s how actually things went.
Immediately after the Big Bang, we think that the universe was made of pure energy. Energy can turn into matter and vice versa, so the idea is that this energy at a certain point became matter and antimatter, and that the former created the stars and planets of the universe. We don’t know what happened of the antimatter, that is, a sort of ‘mirror’ matter (an evil twin if you want!) which explodes back into it when enters in contact with matter, destroying it. It sort of vanished. This is one of the big mysteries physics is trying to solve these days.
When the universe was just a ball of energy, the laws of physics were different. There were no forces like gravity, electrical attraction, magnetism etc.: all forces were a single, unified, force, the same for everything. We don’t know anything of this mysterious “original force”, or how the universe worked back then. This situation lasted only for the first few seconds of the universe’s life anyway: after that, it quickly “cooled down” as the initial explosion, so to say, lost momentum, and matter formed. 300,000 years afterwards, atoms were born, and after them came stars and planets.
What caused the Big Bang, or what was there before it? We don’t know. Even time itself was born with the Big Bang, so asking what happened “before” doesn’t even make sense. One of the greatest physicists of our time, Stephen Hawking, believes the Big Bang was just something that happened by chance. In Quantum Mechanics, many things can happen randomly, so it would not be so weird to think that the Big Bang is the same. Still, we don’t know from where did it come from. Is our universe contained inside another, bigger universe? Or was it born from a sort of cauldron, a sea of boiling energy that creates universes like soap bubbles emerging from a hot bathtub? It’s probably impossible to know: for now, we have no way of looking beyond the boundaries of our universe.