In George Orwell's book 1984, could Big Brother actually have been Emmanuel Goldstein?

We could be the same, but only in the sense that we were both fabrications by the Party for their own ends. Big Brother was created to fulfil the need of the Outer and Inner Party comrades for a focus for their faith in Ingsoc, while Emmanuel Goldstein was created as a hate figure for propaganda purposes. Since neither of us actually exist, we will never 'die' so can be used in this way forever.