If you do not believe there is a God now would apologize admit you were wrong to those you have disagreed with?I would have nothing to apologise to anyone for, except possibly God, since disagreement and argument are healthy (this is a debate board, after all).
If I (or you) had ever persecuted anyone based on their beliefs, and were later proven to be wrong, and them right,
then an apology to them would be in order. Otherwise, no.
I'd admit I'm wrong in the face of undeniable evidence that proved me so, yes. I wouldn't enjoy the process much, but who does? But I'd have to admit I was wrong - that's the thing about us secular rationalists, we do end up fitting our worldviews to the evidence, since that
is the rationalist worldview - don't believe anything that isn't evidence based.
If a deity were to spontaneously call itself into existence for long enough to pronounce to the whole universe "listen, I didn't exist before just now, and when I've finished talking I won't exist again for all etenrity. I just spontaneously called myself into existence to say that all the religious people are wrong, and I don't exist, and life and the universe really is a random series of probabilities taking place under accidentally appropriate laws of physics, so stop waiting for me to come and make everything better in your life, or the imaginary one you think you might get afterwards that you invented to allow yourselves to put up with stuff you don't like about this one, and start treating one another, and the rest of the universe, with the respect they and it deserve", religious people wouldn't have to apologise to anyone just for being wrong.
But I daresay they'd find a lot more reasons to fit the evidence to their worldview - because that, almost by definition, is what you have to do when your worldview is based upon faith. "It wasn't God, it was the devil/ a rationalist trick". Or "It was a test of faith". Or, "it wasn't my God who was saying He/She doesn't exist, but his over there". I can easily imagine most religious people coming up with these in the face of hard evidence that there is
no God; any number of explanations why they can carry on believing as before and ignore what's in front of their noses.
Mind you, I can't imagine what the evidence of absence of a phenomenon, for which there is little or no real evisence in the first place, might be.
If you do believe there is a God now would you be all I told you so!Doesn't apply.
What about what you believe (besides that there is a God) would change?Not very much about the world at large.
The believers in whichever particular deity was represented by the talking shiny thing would become even more insufferably convinced of their own righteousness.
After some suitable period of chastened humility at their telling off over the stuff they've got wrong, it can only be hoped.
But I'd wager it would take the form of "Yes God, we're really sorry we ignored that stuff about pork and shellfish being unclean, and spent so much time hating and killing people who believe slightly different things about you, but at least you're saying Jesus/Mohammed/the Flying Spaghetti Monster is your true representative on Earth, so we were right about that bit, and like all righteous people, we like nothing better than to be proven right. Take that, all your doubters/infidels/unbelievers. Now we've got an extra excuse to smite you on behalf of our newly awakened faith, especially now that the ten minutes are up and our God has gone away from his talking light manifestation again, so He won't be able to tell us off again if we're mean to you."
And believers in the faiths who turned out to be wrong (or just to have misinterpreted the talking ball of light's message more dramatically than most) would probably find ways of blaming the appearance on the devil, tests of faith,
et cetera as before.
Most agnostics would become believers, provided they didn't actually have to turn up at a place of worship or change their lifestyle or anything.
Some atheists would persist in their unbelief, because for them their non-belief is a kind of belief in itself (they'd be like the proven-wrong faiths; they'd spend all their energy thinking of reasons why the ball of light was a parlour trick of some kind, designed to con the gullible and the weak).
I believe, most atheists are like me, though - rationalists that are only functionally atheists because there is no solid evidence that God exists, and even less that this particular faith or that one is the one He wants us to follow (they all claim to be, but not all of them can be). Present them, and me, with completely solid, repeatable evidence that we can witness with our own senses (better still if we can do it in a double-blind trial), and we'll find it hard
not to believe.
You have 10 minutes with God - What do you say? Ask?Lots of things, mostly in respect of my scepticism:
1. Who or what created you?
2. What's this big thing you have about being worshipped? Why should an omnipotent omniscient super-being be so insecure?
3. Why are you so hooked on irrational belief - you'd have a lot more followers if you gave some tangible and above-all incontrovertible evidence that you exist. Most of the really smart, people, to begin with

*
For example, you could have done the whole talking ball of light thing all along, instead of only appearing to small groups of people, or single individuals, in poorly corroborated events that mostly took place 1500+ years ago.
4. Why create suffering, hatred, etc? Is the free choice to be good and to worship you
so important to you that the choice to do nasty things that go against everything you say you want people to do, and on a vastly larger scale, is worth the payoff?
5. What really happens after we die? Please don't demonstrate, explain.
6. Please make it easier for us to understand you. If you pass beyond understanding, why not make us smart enough to catch up? Or just explain yourself in simpler terms? Why make us sentient enough to want to understand, but not sentient enough to understand? In other words, faith?
Reading those back, I guess most of my questions revolve around not really getting why any deity would create a creature, and demand it's love and loyalty, but refuse to give any reason to do so beyond "because I say so", which requires the believer to have faith. I don't get why faith is necessary, beyond some kind of supernatural egotism.
Put it this way, I can imagine it might be a huge kick to a man who could breed a new type of ant that could do his bidding, or even just all acknowledge his presence in some kind of antish worship. However, I can't imagine what the ants might get out of it.
* Ok, so maybe now I have something to apologize for.