michael^3 wrote:Maybe the question should be rephrased like "Is it possible that not all behavior of the universe can be predicted/modeled/simulated by an algorithm?".

Yes, that is a better question, but I'm not sure it what Penrose is after.

Preno wrote:the question of whether the universe is deterministic is simply the question of whether we can determine its future behaviour.

Err, no. The question of whether the universe is deterministic is the question of whether there is more than one causal path the universe can take. Our ability or not to determine it is irrelevant. Are you seriously suggesting that the universe could not be deterministic if we were unable to determine its future behaviour?

Edit: Already covered by susu.