The universe is 13.7 billion years old, meaning we can see objects 13.7 billion light-years away due to the face that light travels one light year per year (obviously). At the edge of this "visible universe" is what's called the cosmic background radiation, which is radiation emitted by the big bang itself. It is not actually light, due to visible light not being in large enough quantities to see until some time after the big bang, but it is still detectable.
Matter is made of particles, the most elementary of which are just excitations of energy. This means that everything in the universe is just energy (anything that is not a particle or antiparticle is non-excited energy). The net energy of the universe is exactly ZERO, meaning it could have burst out of nothing, and could have caused itself, due to the fact that there are 26 dimensions of time and 26 dimensions of space. This 26x26 dimensional space time is proven by a theorem known as the the Polyakov action.
LINK TO PDF EXPLAINING THE POLYAKOV ACTION:
The big bang was scientifically proven!!!! You can not just say that something did not happen from a book for all we know god made the big bang this is just like evolution maybe god created it to for all we know the big bang is still spreading but yes it did happen
There is a lot of empirical evidence supporting the theory of Big Bang to the point where it can be considered as a fact. Firstly, we have Hubble's Law which demonstrates that the universe is expanding. Secondly we see the cosmic microwave background, which is a consequence of Big Bang. We also observe an abundance of primordial elements, whose measured quantities roughly correlate with theoretical values. Additional evidence can be obtained from the observations of galaxies and their distributions and the observations of primordial gas clouds. In short, it seems very difficult at this time, if not impossible, to propose a valid and empirically supported cosmological theory that contradicts the concept of Big Bang.
We know through tons of validated research that the universe is expanding at an accelerating rate. We also know that the universe is expanding in all directions. If the universe is expanding in all directions, and its accelerating, that means a huge explosion must have occurred from a single point.
For those treating the big bang like a "philosophy", you need to realize there is actual evidence that can be observed right now that support this theory.
Though I suppose it could be possible, the fact of the matter is that no one knows how the universe began. You can claim to know. You can say that you know God created the world or that you ran the numbers of the universe or whatever, but you can't know for sure. You weren't there when it happened, and it's words on the page are meaningless in respect to this topic.
According to a scientist named Eric Lerner, the big bang never happened. He wrote a very controversial book about it in 1991.
It does not seem like he has changed his mind yet in spite of others claiming his book is filled with mistakes.
There is a PDF download on the site for those interested in technicalities.