Is there or will there ever be an accepted theory that unites relativity and quantum mechanics?If there is will that be the final answer to everything or will there be more to discover?
It won't really tell us how the Bigbang came about will it? If there is a how?
I think it will probably explain the very first 'instants' 'after' the Big Bang, planck time, currently unexplained by science. Inexplicable.
Look at the people who declared aeroplanes to be a fantasy. Someone at IBM once predicted that the world would never need more than five computers.
Look at the old ideas of where we'd be in 2000 - living on the moon in tin foil suits.
People are shockingly bad at saying what will and will not be possible in the future.
It is the height of arrogance to claim to know what human endeavour and ingenuity will not be able create or think up in the future.
Will we ever have a good theory of quantum gravity? - probably yes - whether it turns out the way we think is another
But that's not really a theory of everything - there's more to it than uniting the forces. You need to explain the nature of the fundamental particles and the so called free variables
Why are there 3 generations of quark and lepton?
Usually patterns like this indicate an underlying structure - but we can't see one.
Why are the strength of the coupling constants of the forces what they are?
At the moment our theories take these values from experimental evidence - we don't know why gravity is as strong as it is why the electric charge is what it is?
150 years ago some people thought physics was nearly done and just had a couple of odds and ends to clear up. - Those odds and ends have totally transformed our understanding of physics and the nature of reality.
It's easy to think we're in that same situation again - those questions have all the signs of being the real biggies.
The plank time and big bang is a bit of a red herring because our language gets in the way - to talk of before the plank time is like talking about standing of the "one half-th" rung of a ladder.
And all of that is avoiding the "elephant in the room" he's been standing there for about 80 years now - A great big "Bull tusker" with "Quanatum mechanics interpretations" written on his side and if you look carefully hovering over his head in a very Lewis Carrol sort of way you may just see the mocking smile of Schroedinger's cat!