Einstein was a member of the Manhattan Project that was responsible for the development of nuclear weapons for the United States during World War II. And his most famous equation, E=mc2, underlies the principle of converting matter into energy, extracting it from the nucleus of atoms, for example. And yet, a bit more than a decade before the first nuclear test, he did not believe it was possible to actually split the atom.
“There is not the slightest indication that [nuclear energy] will ever be obtainable. It would mean that the atom would have to be shattered at will,” Einstein told the Pittsburgh Post-Gazette on December 29, 1934.
The first sustaining chain reaction that allowed scientists to create a controlled release of nuclear energy was obtained in 1942. This was called the atomic pile, the precursor to what we now call the nuclear reactor, by Italian physicist Enrico Fermi and his team at the University of Chicago.
Theory Of Everything
Until his dying day, Einstein worked tirelessly trying to combine quantum mechanics and relativity into a single coherent system that could explain every object and every phenomenon in the universe. He, unfortunately, failed at it, and on top of that, he didn’t even get close to the final theory. That was not his fault as he was missing a lot of knowledge about the universe that we now have. For example, he didn’t know about the existence of the weak and strong nuclear forms (at least not in their current definition).
But extra knowledge doesn’t mean we are any closer to finding this theory of everything. Several hypotheses have been put forward, like string theory or quantum gravity, but we haven’t found any definitive proof for either. Or it's something else.