God has detectable manifestations, but God is not a thing that science can test. Science does not know how to test for God or what God does to make things happen in the material world.
This may be the reason that science has a naturalistic methodology but does not say that God does not exist.
What are you referring to as detectable manifestations? Detectable by what methods?
At present, the only 'detectable' anything is by scientific methodology. This is the reason science CANNOT say whether God exists or not.
What is the difference between the universe contains material and the universe is made from this material?
Is that a special definition of "the universe"?
I try and keep things simple. One definition most common is our universe that began(?) with the expansion of matter and energy from a singularity or in some way cyclic. I do not like the term 'Big Bang,' There was no Bang. ALL the current hypotheses or models of our early universe are based on the existence of a Quantum World where a singularity formed or a cyclic expansion took place. The concept of T-0 is a beginning where the three or more dimensional space and time as we know it on a large scale began to exist.
There are many unanswered questions, and most of the indirect evidence is based on math models and Quantum Mechanics fit well withe alternate scientific views of the early universe, and what has been theoretically possible is a boundless universe,
Is the age of the Universe "boundless"?
I was reading this Quora post, and it seems to say that the late, great Stephen Hawking has proven this. https://www.quora.com/Have-scientists-disproved-Stephen-Hawkings-theories-of-the-universe His work in both areas has shown that time is boundless in both directions, both forwards and...
www.physicsforums.com
Note, btw, that Hawking's actual proposal for a universe being "boundless" in the past, which was called the "no boundary" proposal, was not that the universe had existed for an infinite time in the past, but that the spacetime geometry of the very early universe was such that "time" had no meaning there and there was no starting boundary. Basically, instead of the geometry of the universe either extending infinitely into the past or having an "edge" at an initial singularity, it would be more like a hemisphere joined to an expanding cone, with the join being something like the big bang (or possibly the start of inflation). The "expanding cone" part is the part which can be viewed as a conventional expanding universe. The "hemisphere" part is the "no boundary" part, where "time" is not a meaningful concept--it doesn't extend infinitely into the past (since the hemisphere is finite), but it also has no boundary (since the hemisphere has no edge anywhere). AFAIK this proposal is not currently considered a contender for a valid model of the universe. But I'm not familiar with the details of why it is not.
The other 'universe is the physical existence that contains our universe and all possible universes.