"This problem will be solved in your lifetime?"
"This will be solved by your children/grandchildren?" (But has been solved recently by someone in your own generation?)
"One of you will win a prize (that is not the Nobel)?" (The X Prize, perhaps?) Space program relevant? Celebrities relevant ("You will see the first television personality nominated for president")?
Hm, "A (black) president will win the Nobel Prize someday?" If not, should we be using or combining elements of the two very close questions? And is that last question too meta to be a legitimate question for this puzzle?
Oh, wait, you said this was proven wrong. "A black man will never be president?" "A black president will never win the Nobel?" (Hm, that can't be it, since Mandela was a president and won a Nobel.)
Double Oh Wait, you said this was an optimistic story... "A black president will win the Nobel in your generation or the next?"