Only two things can make me convinced that there is no God:
1) If science can show that this universe does not need any God; and
2) If science can show that God of the theistic description cannot exist.
Regarding 1), it should be said that no one on this earth can claim that he/she is omniscient. Therefore no one on this earth can claim that he/she knows with absolutely certainty that there is no God. However scientists can come to know that there is no God if they can show that everything in this universe, including its origin also, can be explained by natural means without invoking any kind of god. No doubt this is a very lengthy process indeed, but at the end of this lengthy process one can with some certainty say that the universe does not need any God.
However it has already been shown here1 that the origin of the universe has not been explained properly by the scientists.
The above shows that science has not yet been able to explain everything of nature by natural means. In such a situation how will the scientists convince us that this universe does not need any God?
Regarding 2) it may be asked: which God? This is because there are thousands of religions on earth and each religion has its own concept of God. I have already made this point clear here2.
This God is spaceless, timeless, changeless, immortal, all-pervading, one, unborn, uncreated, without any beginning, without an end, everlasting, non-composite and immaterial.
So in order to show that this God having the above attributes cannot exist, scientists will have to show that no one or nothing in this universe can be spaceless and timeless. Then it can very easily be argued that this God does not exist, because this God is said to be spaceless and timeless whereas science has already shown that no one or nothing can be spaceless and timeless. But here science has done just the opposite to what it was supposed to do; it has shown how it is possible to be spaceless and timeless. That means here also science has failed in its endeavour to show that God of the theistic description cannot exist. Here their failure has a much deeper negative impact on us than their failure in the first case, because once they have shown how it is possible to be spaceless and timeless then it becomes next to impossible for them to convince us that this spaceless and timeless God cannot exist. All their efforts will be futile now and all their arguments against God will fall on deaf ears only.
Here I want to add one more point. If we are to bring in a God at all, then we will bring him in not as a mere observer but as the creator of the universe only. So in order to show that this creator God does not exist I think it will be sufficient if scientists can show that the universe needs no creation because it has no beginning, or that even if it has a beginning then that beginning can be easily explained without invoking any kind of god. But I have already shown that science has failed here and so we are not at all convinced that this universe does not need any God.
Scientists have failed to convince us that God does not exist.