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Topic: Algorithm for deriving permutations
Replies: 26   Last Post: Oct 21, 2007 2:16 PM

 Messages: [ Previous | Next ]
 David Bernier Posts: 3,887 Registered: 12/13/04
Re: Algorithm for deriving permutations
Posted: Oct 19, 2007 2:45 AM

> On Oct 18, 5:09 pm, Robert Israel
> <isr...@math.MyUniversitysInitials.ca> wrote:

> > Proginoskes <CCHeck...@gmail.com> writes:
> > > On Oct 18, 2:36 pm, Richard Heathfield
> <r...@see.sig.invalid> wrote:
> > > > hardwidg said:
> >
> > > > > On Oct 18, 10:33 am, Water Cooler v2
> <wtr_...@yahoo.com> wrote:
> > > > >> I thought it would be too cumbersome as in
> the actual problem I have
> > > > >> at hand, the number of "fruits" are about
> 255 and the number of boxes,
> > > > >> about 60.
> >
> > > > > I don't think any algorithm can ever finish,
> since it sounds like you
> > > > > want to list 255^60 entries, which is greater
> than 10^144.
> >
> > > > > The universe has something like 10^80 atoms
> and is less than 10^18
> > > > > seconds old.
> >
> > > > > Even if you had every atom working for the
> life of the universe, you'd
> > > > > still need them to create 10^46 entries each
> second! Even if they
> > > > > could make one entry per Planck time, you'll
> still only be able to
> > > > > create about 1/1000 of the entries!
> >
> > > > Just use a quantum computer to tap into the
> computational potential of
> > > > infinitely many universes. Total runtime: about
> a sixteenth of a second
> > > > (i.e. as long as it takes you to realise that
> it's finished).
> >
> > > The only problem is that the output is spread
> across 10^144 universes.
> > > Compiling the list in one universe will require
> all the time that you
> > > saved by spreading out the work.
> >
> > > Of course, if you had connections from each
> quantum universe to ours,
> > > then they could write their output all at the
> same time, and it would
> > > work.
> >
> > It would? Where in this universe would they put

> the output? We don't have
> > enough atoms to write each entry on an existing
> atom. And if their output
> > involves adding new atoms to our universe, it'll
> make things rather crowded...
> > and have very serious effects on space-time.

[Proginoskes: ]
> That's right ... This is a finite-matter universe.
> ... It gets so
> confusing when you hop from one to another, doesn't
> it?

From the slides for a talk by Alan Guth, originator
of inflationary models in cosmology:

"If inflation happens once, an /infinite/ number of
universes are produced."

cf.: page '10', starting at:
< http://pauli.physics.lsa.umich.edu/w/arch/som/sto2001/Guth/real/sld002.htm >

P.S.: I think these sub-universes are sometimes
called "bubble universes". But I still don't
understand how and when they would
break off from the rest. Page 10
of the slides has a figure which looks like
negatives of the first steps in forming
the Cantor set.

David Bernier

Date Subject Author
10/18/07 Water Cooler v2
10/18/07 Randy Poe
10/18/07 Water Cooler v2
10/18/07 hardwidg
10/18/07 Richard Heathfield
10/18/07 Proginoskes
10/18/07 Robert Israel
10/18/07 Proginoskes
10/19/07 David Bernier
10/19/07 Richard Heathfield
10/18/07 Randy Poe
10/19/07 David Breton
10/19/07 Proginoskes
10/19/07 Richard Harter
10/19/07 Marshall
10/19/07 Patricia Shanahan
10/18/07 briggs@encompasserve.org
10/18/07 Patrick Hamlyn
10/19/07 mensanator
10/19/07 hagman
10/19/07 Patrick Hamlyn
10/19/07 Richard Heathfield
10/19/07 mensanator
10/19/07 rossum
10/20/07 Grouchy