Do you have an example of a truly random phenomenon?

In summary, the author is looking for a truly random phenomena that is not related to quantum physics, and they can't think of anything. If all of the data about the phenomena were known, it would still be random.
  • #106
sysprog said:
I'm confident that you well know that XOR means one or the other is true, but not both, whereas XNOR (IFF) means either both are true, or neither is true − they're similar; in that one is the inverse of the other, but they're not what I would call "really the same".
NOT(XOR) = NXOR = XNOR; which is just another word game.
Randomness is independent of signal polarity.
The power spectrum is independent of signal polarity.
Minimising entropy is independent of signal polarity.
The vast majority of signals are independent of polarity.
Does a telephone conversation sound different if the twisted pair has the mate and colour swapped ?
 
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  • #107
Baluncore said:
Does a telephone conversation sound different if the twisted pair has the mate and colour swapped ?
Rhetorical question?
 
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  • #108
NTuft said:
To quote an answer from a more knowledgeable person than myself on the topic, given to me from a question I posed as, "Can you generate a random number from a machine?"

Not sure that's all relevant, or that I can support the assertion, but that is the mostly complete answer. He seemed to be aware of something similar vis a vis white noise generators for randomness.

I want to also reiterate that I believe radioactive decay is considered stochastic (random?) at the individual atomic level. From the wikipedia on radioactive decay, we can see there are some applied methods that work from the premise that radioactive decay is random:from: https://en.wikipedia.org/wiki/Radioactive_decay
I seem to remember some programs using noise from GPUs (how the audio [EDIT: Yeh ok, bad word] was captured I can't seem to remember...) to seed random number generators. Theoretically at least, one could use the noise from a *NIX HDD shredding data and base your numbers on that.

I admittedly didn't read your entire thread though. If I know you guys just superficially you probably already descended into some black hole entropy theory or something, where, as normally you couldn't get out, I wouldn't be able to get in in the first place. :)

Regards.

Stumbled across this, admittedly a little dated, reference:

Quantum Random Number Generators

Although I think skimmed enough to understand that quantum randomness wasn't really the subject.
 
  • #109
gmax137 said:
Rhetorical question?
Presumably ;-)
 
  • #110
What if all information CANNOT be known? For example, pi. Then a truly random number would be the decimal value that is just past the knowable value of pi.
 
  • #111
Art G said:
the decimal value that is just past the knowable value of pi.
There is no such thing as "just past the knowable value of pi". The problem is that for any rational number greater than ##\pi## there exists another smaller rational number also greater than ##\pi## (thus even closer to ##\pi##).
 
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  • #112
Nugatory said:
There is no such thing as "just past the knowable value of pi". The problem is that for any rational number greater than ##\pi## there exists another smaller rational number also greater than ##\pi## (thus even closer to ##\pi##).
Can we generalize this a bit more? e.g. 'for any real number that is greater than another real number ##x##, there exists another lesser real number that is also greater than ##x## (wherefore such a lesser exceeding (greater than) ##x## real number is closer to ##x##)' ##\dots## :wink:
 
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  • #113
Art G said:
What if all information CANNOT be known? For example, pi. Then a truly random number would be the decimal value that is just past the knowable value of pi.
For pi, all information actually can be known. But let us evaluate your conclusion instead for Chaitin's constant. In that case, all information cannot be known. Does that mean that its digits are truly random numbers? It is known that they actually pass any mathematical test for being uniformly distributed and independent (just as good as truly random numbers). So it will be hard to refute your claim mathematically.

But can you give positive arguments for your claim, and explain why we should accept those digits as truly random numbers?
 
  • #114
Art G said:
For example, pi.

gentzen said:
For pi, all information actually can be known.
Two different 'experimenters' can calculate the nth digit in pi and they will get the same answer. There's nothing random about that. I can't imagine that 'nearly random' is a very meaningful term. But Mathematicians may say otherwise - as they do about the various levels of Infinity.
 
  • #115
Wouldn't a high coin toss in a turbulent air flow effectively be truly random for all practical purposes?
 
  • #116
bland said:
Wouldn't a high coin toss in a turbulent air flow effectively be truly random for all practical purposes?
Yes, but put the word “truly” in there and suddenly nothing qualifies. That isn’t unique to randomness.
 
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  • #117
@Dale,

OK, I got led to an apparently 'related thread', and this quote by @Vanadium 50 ...

1. What is the difference between "random" and "truly random"? (And truly truly random, and truly truly truly random, etc.)
2. What measurement would convince you that one or the other is correct?


Well not sure if I'm being asked the same question in a different way, but what I meant, by 'truly' was a randomness without any qualification for example a radioactive decay event. As opposed to some other not 'in principle' randomness but just as good for all practical purposes.

So regarding the thread topic, I am asking the question would a coin toss into a chaotic turbulent air flow be considered as random as which path a photon would take on a 50/50 semi reflecting mirror. Or would it be considered solvable 'in principle' like the way an ordinary coin toss is said to be not random if you knew everything there was to know, blah blah and so forth.

This is a question.
 
  • #118
Bit faults in RAM due to 'cosmic rays' and back-ground radiation as an example of 'random detections' ?

With proviso that cosmic ray flux is modulated by solar cycle, while Radon flux may vary with atmospheric pressure and water table height...
 
  • #119
The_Baron said:
I mean that if we had all of the data we could have on the phenomena, then even theoretically it will still be random.

The primary random order of the universe.
 
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  • #120
"

Do you have an example of a truly random phenomenon?​


"

do you have an example of a truly right triangle?
 
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  • #121
The_Baron said:
I mean that if we had all of the data we could have on the phenomena, then even theortically it will still be random.
I have real trouble with the format of this discussion board. Nonetheless, on the grandest scale the universe is random, random as the expansion and creation of new synapses and thought paths in the brain with new, especially original thought. At the inception of a seemingly intentional thought, was the thought to carry out, or even conceive of the intent, random? Is photon distribution in the Slit Experiment, random? So in the random but contained expansion of the universe, there is order universally in universal randomness. Yin & Yang, I reckon. Like it's getting to the philosophy of science/physics.

Mu
 
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  • #122
Automaticsteam said:
I have real trouble with the format of this discussion board.
I love the format of this 'discussion board'. It's briliiant.
 
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  • #123
Automaticsteam said:
Like it's getting to the philosophy of science/physics.
And in a random act of kindness, this long thread is now done. Thanks everybody for your contributions.
 
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