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

Re:Non-Universality in Computation: The Myth of the Universa... by stonemetal on Thursday April 16, 2009 @12:20PM (#565367)
Isn't this more or less the same issue as multiple infinities. Whole numbers are infinite but countable, but rationals are infinite and not countable. UTMs are able to compute the infinite but there are infinities that are not computable.
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Re:Non-Universality in Computation: The Myth of the Universa... by banned_man on Thursday April 16, 2009 @01:05PM (#565433)
Rationals are countable but dense. You can biject Z * Z <-> N trivially (start from origin, spiral out) and Q can be constructed as a subset of Z * Z. Reals are uncountable.
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