Re: Imaginary Polynomial Time Algorithm for Subset sum Problem

On Fri, 07 Mar 2008 09:49:46 +0100, Tim Tyler <seemysig@xxxxxxxxxxxxxx> wrote:

Patricia Shanahan wrote:
Tim Tyler wrote:
Jym wrote:

And that's also the problem with the OP stamping process: it can copy an arbitrarily large number of dots in a single unit of time. While on any realistic computer/model, copying an array (typically), would take time proportional to its size.

FWIW, copying an array does not take up time which is proportional to the size of the array on a parallel computer.
Are you assuming a bounded or unbounded number of processors?

Well, more copiers than the array size. Otherwise it is true
that things may start to slow down.

My model of a big parallel machine is rather like the model of
a Turing machine - more processors can be added if they are
needed for the problem's processing - or indeed its I/O.

But then, as you mentionned, creating new processor "should" take time function of the number of already existing processors to have a realistic model.
This is not the case of the OP's stamping process which copy as many dots as wanted in time 1 without explicitely creating all these processors.

--
Hypocoristiquement,
Jym.
.

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