No. No one does, and no one can prove or disprove God. God exists beyond the realm of proof. If you wish for theories, many of us have them and can logically explain them and personally attest to what we perceive to be God's hand at work. Others attribute the same evidence to random chance.
Paraphrasing Romans 1:19,20 What we can know about God is plain to us and clearly understood by the things that are made, so those who deny Him are without excuse. And we really do understand this. We see the marvels of the universe, life and all creation. No matter where we look, and whether we look up to the heavens or down into the smallest cell, we see the print of God and of design. We must make an effort to deny the evidence of design, so that the even the Atheists concede they see what "looks like it was designed." Consider DNA and the huge amount of information in it, that makes Bill Gate's WINDOWS look trivial. So God says if we deny him, we are without excuse for knowing of Him. Unfortunately the passage in Romans 1 goes on to say that there would be those who deny God and worship the creation, rather than the creator, and that is what we see happening even within some of these answers. In the end, we all have faith in something. Either in the creator God, or the spontaneously occurring Big Bang with no causal explanation and in life coming out of a pond of slime...a foundationless faith in the nothing that began it all. I choose faith in God.
Faith can't be proven. That's why it is faith. To prove it would defeat the purpose of it. It's easy to believe in something you can prove. Faith demands discipline, and is tempered in doubt. If you've never doubted your faith, you've never really had it.
There are three ways of inferring the existence of something: direct observation, indirect observation, and testimony. You can either see the object, see the effects the object has on something, or take testimony from experts or other direct observers. Everything short of direct observation requires a measure of faith or trust, and direct observation may not ever be complete. For example, Prove the existence of God? In truth we must analyse the question before we attempt an answer. What is considered a proof? How does one prove that anything exists? Take, for example, a blind man. Does colour exist for the blind man? He cannot see colour yet it still exists. That fact is established by others who can see. The blind man believes and trusts that his fellow men can see that colour does exist although it is beyond his personal experience.
For a further example, take electricity. When we turn on a light can we see electricity? The answer is no, we see only its effect. Take gravity. When an object falls we cannot see, hear, feel, taste or smell gravity - we see only its effect. All agree that gravity is an undisputed fact of nature - since we see its effect. Scientists today are still baffled as to exactly what is the "stuff" of gravity. And we cannot see a black hole, but we can see its effects. God dwells in deep darkness, in obscurity, according to Scripture. On the one time when he manifested his presence at Mount Horeb, the people asked not to hear him lest they die (evidently it's scary to see God), so He said he would never again be directly seen, but would talk through his servants (and the Prophet). So, we must rely on indirect observation and testimony. On indirect observation, do we have any evidence? 1. Evidence of creation 2. Evidence of conscience 3. Evidence of the religious nature of man 4. Evidence from the life of holy men. 5. Testimony of Moses and the fathers 6. Testimony of other faithful believers 7. Testimony of His word. One may ignore one source of evidence, but one has to be willfully blind to ignore the evidence which demands a verdict.
There is no evidence for or against god, as jk a few people above me stated. The answers and logic pate gave is only circular logic as far as indirect observance (we exist so god must exist). The testimonies he mentions have no basis as no one knows who wrote most all of them, and surely not Moses as if he had it would not have been in Hebrew. The only evidence of god is in the faith you exert to believe and nothing more.
Moses is the only person who saw God before he died when he went unto mount Sinai to receive the ten commandments. Everybody who has ever lived has and will come face to face with God when they die. Everybody will believe there is a God at that time. Unfortunately those who don't believe while on earth will not receive his kingdom.