By John Prytz The origin of our Universe, what set off what is commonly referred to as the Big Bang event, the immediate happening just before the Big Bang event, is currently one of those areas of uncertainty in modern cosmology. So theists propose a theological alternative - God done it. While it is impossible to - as yet - prove that God didn't do it, the God Hypothesis is a very weak explanation at best.
Theists claim that the Cosmos cannot be infinitely old since you can't navigate or undertake a temporally infinite journey and arrive at this, the present moment or "now". While I don't agree, let's take that on board and look at the theist's explanation that the Universe (or any wider Cosmos our Universe is a part of) is finite in duration and had an actual "in the beginning" or creation. Of course according to theists, "God done it" - that's the God Hypothesis.
However, perhaps even a finite Universe is an infinite one. By analogy, Pi has a finite beginning yet it has apparently infinite duration. Or, even if Pi does eventually repeat or come to finality, there's 1/3rd which also has a finite beginning but which is also infinite in duration. Therefore, even if our Universe had a finite beginning, it is still infinite if there is no temporal end to it.
Now it could be the case that the matter / energy content of the Universe adds up to and is exactly zero. The amount of push energy could equal the amount of pull energy or positive energy balances exactly negative energy. A 'zero point' Universe would also require equal amount of matter and antimatter which is where things seem to fall apart since there appears to be way, way, way more matter than antimatter present and accounted for.
But the next problem is, how does a state of nothingness morph into a state of something? How can nothing 'decide' to become something? And is a 'zero point' Universe where push energy equals pull energy and matter equals anti-matter really a state of overall nothingness?
So enter the God (did it) Hypothesis. I have lots of issues with the, and the theist's God Hypothesis.
Firstly, there could yet be a natural explanation as yet undiscovered. Science doesn't claim to know everything under the Sun - yet. Scientists say that it is perfectly A-OK and acceptable to say "we don't know". By postulating that "God did it" theists are just substituting one mystery with another but even greater mystery.
Secondly, there is no evidence that any deity exists (and Christian theists reject most other deities themselves for lack of evidence). If there was such evidence atheists and theists wouldn't be holding a "God done it" / "God didn't do it" exchange and 99.9999% of the worlds human populace would be in the Christian theist campgrounds. It wouldn't ever be 100% for even today there are still some people who believe the Earth is flat.
Thirdly, where did God come from? If God has always existed you're back to the original infinity problem theists keep harping against. Theists cannot give the thumbs down to an infinite Cosmos AND at the same time give a thumbs up to an infinite God. That's a double standard. That's illogical, contradictory and a case of special pleading without justification. Further, if God is temporally finite then who or what created God and doesn't that also imply a backwards causality problem that also ends in infinity?
And please don't give me any nonsense about God 'existing' outside of space and time. Those are nonsense phrases which have no counterpart to any actual brand of reality. Theists can no more demonstrate an 'outside of time and space' than theists can demonstrate a creation of something from nothing which they must postulate if the Universe had an "in the beginning". If God exists He has to exist inside something, even if that something is a perfect vacuum. If God does something, anything, even think of something (which is a ridiculous concept if God is all-knowing) then God exists in time since actions are motions and motions represent change and change is what we identify time with.
Fourthly, after God created life, the Universe and everything, well now that God's unemployed, how does God spend His time day-by-day (in terrestrial units)? Further, it's rather absurd for an all-knowing God to have existed for an infinite amount of time in the past to all-of-a-sudden, on the spur-of-the-moment (a moment that he already was aware of an infinite time ago previously that would come to pass), snapped His fingers (assuming fingers) and created life, the Universe and everything. So it seems that God was unemployed not only after His creation but before it as well.
Fifthly, one of the more ludicrous facets involving the God Hypothesis is that during the era where all those Biblical events were allegedly unfolding, Australia was populated; Africa (south of the equator) was populated; the Americas were populated; Asia was populated; Northern Europe was populated and Russia was populated. Yet, an alleged omni-present God [and later on, Jesus] totally ignored these regions and their populations. So the obvious conclusion is that God was just a mythological invention by the Near and Middle East locals, albeit slightly evolved in concept from the local theological mythologies that preceded the God Hypothesis. Nothing new there. Every populated region on the globe during Biblical times developed their own non-Biblical brand of theology and associated deities and no specific region can logically claim to state that they have absolute claim to theological truth and that all else that originates from other regions is mythological by comparison. And just to add insult to injury, neither Father, Son nor Holy Ghost has been sighted now for thousands of years - oops.
Sixth, so what if the God Hypothesis is wrong and it turns out to be the Brahma Hypothesis or the Odin Hypothesis or the Quetzalcoatl Hypothesis or the Viracocha Hypothesis or even the ancient Greek Hypothesis (i.e. - Hesiod's "Theogony", the Greek counterpart to the Genesis creation myths)? My hypothesis is that when humans wrote "In the beginning" they were doing the same thing as others tried to do in explain lightning with a "Thor done it".
As long as the human intellect and imagination can come up with possible, even plausible natural scenarios for the beginning of the Universe then there is no need to invoke the supernatural. In fact, when looking around at the natural world - life, the Universe and everything - over the course of human history, natural (no free will) explanations have constantly replaced in spades supernatural (free will) explanations*. With every passing day the need for a deity - any deity - is rapidly approaching virtually zero. Remaining mysteries will go the same naturalistic way.
I used to think that the best way to become an atheist (with respect to God instead of say, Zeus) was just to actually read the Bible as an open-minded sceptic. However, I've learned an equally effective way is to listen to Christians try to defend the indefensible.
*Recall the example of how once upon a time lightning was explained by Thor done it.