Right about now perhaps the only way you could get “arbitrarily close to 0” is by scanning Knox’s brain or the actual perpetrator’s brain; if both should die, we would reach a state of absolute uncertainty about the event, all the evidence you could in principle examine to reach certainty will have been rearranged into unintelligible patterns.
You’d have to examine a lot more, but certainly there would still in principle be some finite amount of information (though much of it unmeasurable within the universe, possibly including some in other quantum branches) that would suffice to run the physics backwards (with a finite computation) and figure out what happened.
You’d have to examine a lot more, but certainly there would still in principle be some finite amount of information (though much of it unmeasurable within the universe, possibly including some in other quantum branches) that would suffice to run the physics backwards (with a finite computation) and figure out what happened.