PREDICTING THE DETAILS OF THE UNIVERSE WE LIVE IN, THE THEORY OF EVERYTHING
The calculations necessary to study all the data in the universe are ludicrously far beyond the capacity of any imaginable computer. Hawking points out that although we can solve the equations for the movement of two bodies in Newton’s theory of gravity, we can’t solve them exactly for three bodies, not because Newton’s theory doesn’t work for three bodies but because the maths is too complicated. The real universe, needless to say, has more than three bodies in it.
No começo eu não entendia muito bem como não se é possível tirar conclusões exatas sobre situações e coisas tão recorrentes, tão práticas, cotidianas… tão físicas. Na verdade tinha plena certeza de que era possível: só era preciso tempo e capacidade.
Eu até estava certo, só não sabia que o tempo e a capacidade necessários podem, de repente, ser infinitos.
Nor can we predict our health, although we understand the principles that underlie medicine, the principles of chemistry and biology, extremely well. The problem again is that there are too many billions upon billions of details in a real-life system, even when that system is just one human body.
Even with the Theory of Everything in our hands we’d still be a staggeringly long way from predicting everything. Even if the underlying principles are simple and well understood, the way they work out is enormously complicated. ‘A minute to learn, the lifetime of the universe to master’, to paraphrase an advertising slogan. ‘Lifetime of the universe to master’ is a gross understatement.
© Kitty Ferguson – Stephen Hawking – His Life and Work (excerto, com comentário) – Bantam Books