Hacker News Reader

Comment by iosystem | Hacker News Reader

I think the phrase "true random" is confusing. The author did highlight the difference well between the two. I still wish there was a better phrase for techniques generating randomness that are currently better than techniques generating pseudo-randomness.

View on HN

Yes, its essentially nonsense and seems to come from some quarters of the academic community as well as a marketing/differentiation technique. In reality there are:

PRNGs - pseudo /deterministic, CSPRNGs - crypto secure pseudo /deterministic, HRNGs - hardware based (this can refer to anything from roulette tables to zener diode noise), QRNGs - where the entropy source is quantum mechnical in nature.

Nothing is truly random. Radioactive decay for example is influenced by the Purcell effect [1].

[1] - https://en.wikipedia.org/wiki/Purcell_effect

Under very specific circumstances:

>The radiative properties of an atom in a cavity differ fundamentally from the atom's radiative properties in free space. Spontaneous emission is inhibited if the cavity has characteristic dimensions which are small compared to the radiation wavelength, and enhanced if the cavity is resonant. The cavity causes slight shifts in the energies of the atom, analogous to radiative shifts. [0]

I wouldn't classify it under radioactive decay as in "nuclear change" (here: Potassium-40 as beta minus decay and EC, respectively) as it is a well understood photon-matter-interaction phenomenona (cQED) in e.g. manipulating single photons (single atoms in cavity) deterministically [1] which can be used in turn - coincidentally - in generating true random numbers ... [2]

[0]https://ui.adsabs.harvard.edu/abs/1981PhRvL..47..233K/abstra...

[1]https://www.nature.com/articles/nphys569

[2]https://aip.scitation.org/doi/10.1063/1.3610677

Ideally I would love if we could stop using "random" entirely when referring to PRNGs. Call them "deterministic bit mixers" or something.

We can just call them CSPRNGs to be precise.

The pseudo lets you know it's not real quantum randomness, and the rest of it lets you know it's probably good enough for all practical purposes.

Actually, crypto pseudorandoness can be more appropriate for some things, because you can prove you didn't rig it.

"Anyone who attempts to generate random numbers by deterministic means is, of course, living in a state of sin." -- Von Neumann

Lots of sinners in tech and academia...

I don't think that adds any value over pseudo-random.

perhaps "non-psuedo-random" ? or physically-random, as in, produced by an effect of physics and not an algorithm.

I think "non-psuedo-random" is definitely better for someone approaching the topic from a beginner mindset. It possibly hints that something non-psuedo-random can become psuedo-random depending on how advanced scientific understanding of nature becomes.

pseudo*

I'm more of a descriptivist myself

And I like describing the proper spelling of words :P

Reply on news.ycombinator.com