[Khoth]

> Put another way, Turing machines suck even if you enhance them to have 5 parallel tapes (God why do they not have parallel tapes by default, should have at least one for output, one for main memory, one for a stack, and some more as scratchpads)

You answered your question as you asked it. If you juice up your Turing machine like that, it will still suck so much that nobody will actually write programs for it, but it will be more complicated to describe and analyse.

[kaba0]

I think he/she was just “sarcasticly” extending Turing machines to show that even in practicality its limits apply.

But for those who may not know, you can emulate an n-tape Turing machine with a single-tape one, they are computationally equivalent (and in fact, there is no stronger model of computability)

[wizeman]

> You answered your question as you asked it. If you juice up your Turing machine like that, it will still suck so much that nobody will actually write programs for it, but it will be more complicated to describe and analyse.

Of course. Why would you do that? You don't have to.

You can write a program in a Turing-complete language and yet analyze how it will run on a machine with a finite amount of memory.

For example, when you analyze cycle detection algorithms, which assume that the program being analyzed runs on a machine with a finite amount of states (even if it is implemented in a Turing-complete language), you don't do any of that.

And the currently-known algorithms are very simple to analyze.