On Fri, May 16, 2008 9:50 am, Conor Daly wrote:
> On Fri, May 16, 2008 at 09:26:50AM +0100 or thereabouts, Michael Watterson
> wrote:
>> Gavin McCullagh wrote:
>> >On Thu, 15 May 2008, Michael Watterson wrote:
>> >
>> >
>> >>There are several ways to get one physically are really random.
>> Thermal
>> >>noise is one of the simplest & cheapest. There is a reason why a
>> >>tungsten filament gives a CONTINUOUS spectrum (white noise =
>> thermal
>> >>noise).
>> >>
>> >
>> >CONTINUOUS? Surely it's quantised if you look close enough at constant
>> >temperature? There are a finite number of electronic, rotational and
>> >vibrational modes so there should be a finite number of wavelengths.
>> >
>> >Just curious,
>> >Gavin
>> >
>> >
>> If it was LED, Laser, EL panel, CRT, Gas Discharge etc, then yes, there
>> would be obvious discrete quantum energy levels (easily seen with a
>> prism). But it's thermal energy, thus I believe the light really can be
>> any wavelength, with the probability very much lower in UV and low
>> IR/EHF microwave. There is a distribution curve. The light energy is
>> I believe kinetic rather than excitation levels of electrons (Gas
>> Discharge, Phosphors (not just used CRT, but UV LED, CFL etc) , EL
>> panels, LEDs, OLEDS (which are more like low voltage EL than true
>> LEDs).
>> Ah, now we're shagged. Sure haven't The Greens banned incandescent
> lights?
> No more tungsten filaments...
>I have volunteered to sit on the Green Party Science & Technology Policy
Group where there is a working group looking at all things technical.
However I don't think tungsten lights as random number generators will be
of much interest.
However the policy group are more interested in challenging some of the
psuedo science such as that which resulted in the tungsten light bulb ban.
CFLs have an environmental cost. CFLs need to be triple bagged and
disposed of separately from other household rubbish because of the mercury
content. CFLs do not emit a full spectrum of white light so there are some
health downsides to their use.
Seemed like an easy decision at the time for the Greens.
On the subject of math based algorithms. Discovering the seed even if a
random number should be possible as it is just a maths problem i.e. it is
a deterministic process. The only secure cipher is a One Time Pad, where
you need a true random number generator, if one exists.
--
David Howe
Managing Director
Howe Systems Limited
Tel: +353 402 93030
Mob: +353 86 173 1754
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Place of Registration: Dublin, Ireland.
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