Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » sci.math.* » sci.math.independent

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

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
David Bernier

Posts: 3,242
Registered: 12/13/04
Re: Simple random number generator?
Posted: Dec 20, 2012 8:06 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On 12/20/2012 03:15 AM, Michael Press wrote:
> In article<87licvisn2.fsf@bazspaz.fatphil.org>,
> Phil Carmody<thefatphil_demunged@yahoo.co.uk> wrote:
>

>> Michael Press<rubrum@pacbell.net> writes:
>>> In article
>>> <0.ef56b5652decd19bb478.20121128013501GMT.87k3t6v7ay.fsf@bsb.me.uk>,
>>> Ben Bacarisse<ben.usenet@bsb.me.uk> wrote:
>>>

>>>> 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.

>>>
>>> I do not see how quantum effects can be used to generate
>>> random sequences. Coherent systems are stable and highly,
>>> if not perfectly, predictable.
>>>
>>> Hardware generated random sequences usually read Schottky
>>> noise off some device (a sound card in a computer) and use
>>> that. This can be modeled using entirely classical physics.

>>
>> Are you sure? Shottky noise is white noise, and thus is
>> indistinguishable from thermal (Johnson-Nyquist) noise.
>> So you can statistically model it the same way, but that
>> doesn't mean it's actually caused by classical mechanics.
>> I can't find any references to Shottky noise that don't
>> mention some quantum effect.

>
> _What_ quantum effect? So far I am the only one who
> does not gloss over this question. That `quantum
> effects' are involved does not imply that they
> beget stochastic effects.
>
> Experiment and analysis of time series show that
> radioactive decay has an unexplained component. Further
> this unexplained component is no more complicated or
> less simple than diffusion across a membrane. Bluntly,
> equivalent to deflation of a bicycle tire.
>
> By `quantum' I read `wave theory of matter'. The
> original Bohr theory is as good as we have for what
> might actually be happening.
>
> (Personally I do not adhere to any interpretation used
> to psychologically make the experiments more palatable;
> preferring to confront as best my faculties allow the
> raw facts.)
>


We tend to take "measurement" as an objective practice.
But I think there's a subtle interplay between theory
and practice or experimental physics.

Measuring is a phenomenon involving physicists, their
apparatus and what they're observing. (maybe? )

In practice, a sophisticated measurement relies on a long
chain of observations, calculations and assumptions on
what's negligible. These days, it will likely invoke
electro-magnetic theory, since digital measurements
are so common .

The statistics of quantum mechanics has to do with
"observed things", the result of measurement in the
wider sense (approximately).

What is "measuring" in physics, in a once-and-for-all
definition?

dave




Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.