They won’t find the source of the universe…ever! For one, they’re looking in the wrong damn direction. And two, they are looking for some-thing or that has some physical characteristic that can be seen or measured. The story that it started from an incredibly dense and hot, tiny ball of matter, is no different than the stories of most Religions.
The Universe, and the human being observing it and trying to figure out its mysteries, come from, and are made of the same source. In scientific terms, it’s called energy. Energy cannot be seen. It has no form or physical qualities/characteristics. It is not and cannot be created, nor can it be destroyed (first law of thermodynamics). It is uncreated, pure infinite potential which can create. It is intelligent. It is Aware. Another term used for it ,which science doesn’t use but recognizes as a fundamental aspect of existence, is Consciousness. Consciousness, and what they call Energy, are two different words for the exact same thing.
The old question “how does something come from nothing” seems to be a difficult thing to answer until you realize that just because something can’t be seen, or is empty of physical and/or matter like qualities,doesn’t mean it does not exist. What can be created and destroyed (i.e., matter and/or the Universe made of matter) comes from, and is made out of, what cannot be created nor destroyed.