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Topic: Simple random number generator?
Replies: 24   Last Post: Jan 7, 2013 10:52 AM

 Messages: [ Previous | Next ]
 Ben Bacarisse Posts: 1,915 Registered: 7/4/07
Re: Simple random number generator?
Posted: Nov 27, 2012 8:35 PM

"Existential Angst" <fitcat@optonline.net> writes:

> "Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message
> news:0.e12037e9d116e6e9081a.20121127131802GMT.878v9nw5f9.fsf@bsb.me.uk...

>>

>>> On Mon, 26 Nov 2012 15:08:17 -0500, Existential Angst wrote:
>>>

>>>> Would be the digits of e, pi, et al?
>>>> If that's the case, no need for fancy pyooter algorithms?
>>>>
>>>> Inneresting article on pi, randomness, chaos.
>>>> http://www.lbl.gov/Science-Articles/Archive/pi-random.html

>>>
>>> Is it not the case that the digits of e, pi et al. can't strictly
>>> be random, if it is only because they are highly compressible? I.e.
>>> because there small, compact formulas that spit out as many digits as you
>>> want in a completely deterministic way?

>>
>> Absolutely.

>
> Well, as I responded above, Bailey/Crandall would most certainly
> disagree.

No they don't. They use random, quite properly, in a slightly informal,
statistical sense:

It is of course a long-standing open question whether the digits of
and various other fundamental constants are "random" in an appropriate
statistical sense.

Note the quotes and the fact that the term is immediately qualified.

>> Of course, that's also the case for the "fancy pyooter algorithms" that
>> Existential Angst wants to replace, so he or she is not really talking

>
> Well, ackshooly I am talking about true random. Bailey and Crandall are
> hypothesizing that e, pi et al are true random (I like "intrinsically
> random"), but you and others are apparently arguing that because pi can be
> calc'd or generated, it cannot be random. Bailey/Crandall would clearly
> disagree with this.

No, they don't. I am sure they accept the information theoretic
meaning of the word, just as I accept the statistical sense of the term
(especially what in "scare quotes").

> Calculating the digits
>> of pi or e etc (and, presumably, some simple combinations thereof) is
>> harder than the super fast "fancy" algorithms already used, so I don't
>> see the benefit.

>
> Hasn't pi been calc'd to billions of places already? Seems to me that's
> enough random numbers to last people for a while.... lol

Does the lol mean you are joking?

<snip>
> I think "intrinsic experiments", like single-photon slit/diffraction
> experiments would be an elegant way to generate true random numbers -- but
> even that is then dependent on the "legitimacy" of the experimental
> setup.

Good quality, hardware-generated random number sequences (if our current
understanding of quantum effects is correct) are random in a different
way to the digits of pi. It helps if the terminology is be able to
distinguish between them.

<snip>
--
Ben.

Date Subject Author
11/27/12 Ben Bacarisse
11/27/12 Existential Angst
12/11/12 Michael Press
12/13/12 Dr J R Stockton
12/14/12 Michael Press
12/16/12 Dr J R Stockton
12/16/12 Herman Rubin
12/16/12 Michael Press
12/17/12 Dr J R Stockton
12/18/12 Wally W.
1/7/13 Michael Stemper
12/20/12 Michael Press
12/18/12 David Bernier
12/18/12 Phil Carmody
12/20/12 Michael Press
12/20/12 David Bernier
12/20/12 Brian Q. Hutchings
12/20/12 Brian Q. Hutchings
12/25/12 Phil Carmody
12/25/12 Wally W.
12/25/12 Virgil
12/25/12 Wally W.
12/26/12 Dr J R Stockton
12/20/12 Dr J R Stockton