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Re: Simple random number generator?
Posted:
Nov 28, 2012 10:29 AM


"Existential Angst" <fitcat@optonline.net> writes:
> "Ben Bacarisse" <ben.usenet@bsb.me.uk> wrote in message > news:0.ef56b5652decd19bb478.20121128013501GMT.87k3t6v7ay.fsf@bsb.me.uk... >> "Existential Angst" <fitcat@optonline.net> writes: <snip> >>> 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 when in "scare quotes"). [I corrected some of my spelling in the above] > > What is the diffeence between "random" in the informationtheoretic context > vs. the statistical context? > Wouldn't the two be correlatable or translatable in some way?
They are related but they are not the same. I think all noncompressible sequences will be statistically random, but not vice versa (as pi shows).
<snip> >>> 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? > > Well actually, the wiki article I linked says pi has been calc'd to a > *trillion* digits. > The point being, if you need a random sequence, for whatever purpose, you > can just sort of pull them "off the shelf", from anywhere in the sequence. > A trillion numbers oughtta do ya....
The problem is the size of the shelf. It's much simpler to link to small PRNG algorithm than to provide access to a precomputed large sequence.
<snip> >> Good quality, hardwaregenerated 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. > > Which harks back to the above. > Couldn't you take a single photon slit experiment, sample the results > "bytewise", ie, record every diffraction result in groups of 5, and let > those five zero's/one's represent a base 10 digit? Then, you'd have the > photon slit experiment generate irrationalnumberlike randomness.
Why 5?
> In that sense, informationtheoretic randomness (if you would charactize the > photon exp as "informational") and statistical randomness could be > translatable?
I don't know what you mean by "translatable".
 Ben.



