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A comment on Non-Universality in Computation: The Myth of the Universal Computer. Parent comment

Re:Non-Universality in Computation: The Myth of the Universa... by frisco on Thursday April 16, 2009 @01:14PM (#565450)
Example: a function accepts as input the source of another program (assume it's computable and halts). Thus, the original function is variable; can it be simulated by a UTM for any arbitrary valid input? I'm probably using the wrong terminology here, but the overall logic is what I'm getting at.
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Re:Non-Universality in Computation: The Myth of the Universa... by davidmathers on Thursday April 16, 2009 @01:20PM (#565459)
The input to a function can't change (it's a fixed set). If the input changes then you've defined a new function. That's the mathematical definition of a function. You're talking about a set/class of functions, so you would need 1 UTM per function.
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