What do you mean "proof"?
Chemistry does not furnish proofs. Models are built that attempt to explain observed or measured behaviour. Models are always lacking in some regards.
In your original question you asked for a basic explanation and that is what the link provided by sjb givces you.
Please be more specific in what way that basic description is inadequate for your needs. What were you expecting?
Once you have read the wikipedia article follow the "see also" links at the bottom and you will be directed to alternative explanations and models of molecular bonding that are more complex and quite different from hybridization. Chemistry does not provide one, true complete explanation of its phenomena. That is its challenge and reward