
How Randomness Can Arise from Determinism - theafh
https://www.quantamagazine.org/how-randomness-can-arise-from-determinism-20191014/
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peter_d_sherman
Excerpt:

"For a Galton board with any given number of rows, the number of different
paths a marble can take to reach a bin placed at a given row is exactly equal
to the corresponding number in Pascal’s triangle"

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rafaelvasco
Because there's no such thing as random or chaos; Everything follows a
pattern, a protocol, a law; We may perceive it as random or chaos but it is
not; Everything we call random, is in fact pseudo-random; If there's a Law, an
algorithm behind everything, then who or what coded it ? That's the rabbit
hole;

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computerex
This article seems to be starting from a conclusion and then working its way
up to an explanation. That's not how science works. There is lots of
experimental evidence that on a quantum scale there is inherent randomness.

[https://en.wikipedia.org/wiki/Quantum_fluctuation](https://en.wikipedia.org/wiki/Quantum_fluctuation)

Anyone can claim that there are deterministic causal factors leading to what
appears to be randomness. What are those factors? I could claim that invisible
unicorns are the underlying factor for deciding which slit the photon goes
through and this explanation wouldn't be any less supported than the reasoning
presented in this article.

> it might come from subtle factors, including, perhaps, the exact initial
> location of the marble, its angle of motion, or the manner in which the
> marble bounces off the subtle imperfections of the peg’s surface. These are
> all deterministic factors with a clear causal chain that decides which way
> the marble goes. The path selected seems random to us only because of our
> ignorance of these details.

One thought experiment that comes to mind is, imagine a perfect Galton board
where all the pegs are perfectly identical in a closed perfectly isometric
system. Without subtle factors like air currents or imperfections in the pegs
or the marbles, where does the marble land? I think personally if all other
factors are ruled out the thought experiment reduces to the double slit
experiment.

~~~
kerkeslager
> This article seems to be starting from a conclusion and then working its way
> up to an explanation. That's not how science works.

No, it's starting from a phenomena and providing a possible hypothesis for why
that phenomena is occurring. This is explaining an existing, untested
hypothesis.

> There is lots of experimental evidence that on a quantum scale there is
> inherent randomness.

No, there isn't, at least not as far as I know. The experimental evidence I'm
aware of shows that we cannot, with current measurements, model the phenomena
on a quantum scale, except probablistically. It _does not_ show that there
isn't any determinism, it only shows that, with current techniques, we don't
have access to the determinism (if it exists).

In short, this is explaining the "Team E" position:

 _> [W]e debated whether randomness or determinism lies at the heart of
quantum mechanics, which I characterized as team B (Niels Bohr) versus team E
(Albert Einstein). Team B sees the unpredictability of particle behavior as
evidence that at the fundamental level of the universe, determinism is
replaced by intrinsic, objective randomness. Team E contends that this
randomness is merely a sign of our ignorance of a deeper level of
deterministic causation._

To be clear, I'm not saying that quanta are deterministic. I don't know.

> One thought experiment that comes to mind is, imagine a perfect Galton board
> where all the pegs are perfectly identical in a closed perfectly isometric
> system. Without subtle factors like air currents or imperfections in the
> pegs or the marbles, where does the marble land? I think personally if all
> other factors are ruled out the thought experiment reduces to the double
> slit experiment.

Assuming a perfectly drop as well, my hypothesis is that the ball would land
on the top peg and balance there, perhaps after bouncing if we're assuming
some elasticity in the components of the system. A "perfect drop" being in
this case, one where the ball is perfectly centered, with no spin or side-to-
side motion.

But I think this is getting into why analogies aren't a very good way to talk
about science--analogies don't prove anything, and always fall apart on some
details.

~~~
computerex
Also:
[https://en.wikipedia.org/wiki/Bell%27s_theorem](https://en.wikipedia.org/wiki/Bell%27s_theorem)

In conjunction with
[https://en.wikipedia.org/wiki/Lorentz_covariance](https://en.wikipedia.org/wiki/Lorentz_covariance)

Lorentz invariance has not shown to be violated despite many tries
experimentally and from observation.

~~~
n4r9
Bell's Theorem is really about locality rather than randomness. It's possible
to define quantum theory in terms of deterministic but non-local random
variables. In fact, this is a pretty apt description of the de Broglie-Bohm
interpretation.

~~~
computerex
You are right, but any non-local variable theory cannot be lorentz invariant.

~~~
n4r9
I don't think it's that simple. A fair amount of work has been done on
relativistic extensions of de Broglie-Bohm type theories, e.g.
[https://arxiv.org/pdf/quant-ph/0406173.pdf](https://arxiv.org/pdf/quant-
ph/0406173.pdf)

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byron_fast
Is this really any different than the exhaustive investigation of automata by
Stephen Wolfram?

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simplebuilder
Wonderfully informative! Love this author since his days writing about puzzles
for the New York Times!

