[DittoJed2]

Science is based upon observation. Since science requires that SOMETHING be present in order for something to happen then the theory that NOTHING existed and brought forth SOMETHING is not scientific nor is it observable. You can hypothesize, but it is nonsense.

[Right Wing Professor]

In fact, modern physics requires that something (virtual particles) is created out of nothing, every instant of time. And the measured values of several physical constants depend on that creation of something from nothing.

[Physicist]

Science is based upon observation.

Indeed, but we have many ways to observe. We are not limited to telescopes.

Since science requires that SOMETHING be present in order for something to happen

I can think of at least three ways to interpret this statement; would you clarify this?

then the theory that NOTHING existed and brought forth SOMETHING is not scientific

According to any Big Bang model I know of, there never was such a "time when nothing existed". All you are shredding is your own misconceptions regarding the Big Bang.

nor is it observable.

You are mistaken if you believe that a thing must be directly observable in order to be accessible to scientific inquiry. The criterion for science is whether a model makes testable predictions. This the Big Bang does very well. It has survived more rigorous and quantitative observational tests than all but perhaps four or five models ever devised by mankind.