jbergman
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Exactly. I don't think people understand how nasty real numbers and that most are uncomputable.PeroK said:@Dale can you suggest an experiment that would produce any real number (in an interval, say) and prove (or at least justify) why any real number could result.
I assume you accept that most real numbers are indescribable (uncomputable), and the set of computable numbers is countable with measure zero. From that point of view, your experiment could at best claim to have chosen a real number, but could not specify which one. And, in particular, if two such experiments were carried out there would be no algorithmic way to test whether the numbers are equal.
This is a key paradox of the real numbers. We can test mathematically that ##x = y##, where ##x, y \in \mathbb R##. But, there is no terminating algorithm to check whether two real numbers are equal. Unless you restrict things to the computable subset. IMO, that is a good example of where a simple piece of mathematics (If ##x = y \dots##), is not actually physically/algorithmically possible.