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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 e

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.

homonculus1 7y ago
>Without subtle factors like air currents or imperfections in the pegs or the marbles, where does the marble land? If everything is truly perfect, it lands on the first peg.
- computerex 7y ago
  Does it fall to the left side of the peg, the right side, or does it stay on the peg?
  - homonculus1 7y ago
    It comes to rest perfectly balanced on the peg. I intuit that the quantum effects are a wash on the macro scale, but maybe I'm talking out my ass.
    - computerex 7y ago
      What if the size of the peg is really tiny, let's say a few atoms and what if the marble was also very tiny, a single atom? What would happen then?
  - deleted 7y ago
    [deleted]
jayd16 7y ago
But that is clearly the wrong reduction. Start position will determine the final position every time if we assume a perfect board. Marbles are not wave particles. You get a distribution based on the input distribution.
- computerex 7y ago
  It's a thought experiment. If we assume a perfect board with perfect marble with all other factors like imperfections/air currents removed and with the same initial position, and let's say the perfectly spherical marble hits the peg dead center every single time, does the marble fall to the left side of the peg or right or does it not fall to the either side?
  - jayd16 7y ago
    Assuming it lands perfectly in the center, it rests, perfectly balanced on the peg.
    - computerex 7y ago
      What if the size of the peg is really tiny, let's say a few atoms and what if the marble was also very tiny, a single atom? What would happen then?
      - jayd16 7y ago
        I can assure you I don't know. That moves the problem from platonic shapes to real interactions of quantum particles. Atoms are not equivalent to perfect spheres.
criddell 7y ago
> Anyone can claim that there are deterministic causal factors leading to what appears to be randomness. What are those factors? What's the alternative? That something happens without a cause?
- bonoboTP 7y ago
  I mean, things could be that way. It's not so hard to imagine a universe where some events just happen without any causation or correlation with past events. The astonishing thing is that there is any causation at all! That events at different times are related to each other.
  - criddell 7y ago
    You think a billiard ball that just starts moving for reasons of randomness is less astonishing than a billiard ball that moves because it was struck by another ball?
    - bonoboTP 7y ago
      Of course we are already used to things being that way. But a priori, order is what needs explanation, not orderlessness. The interesting thing is that there is movement. That there is temporal structure. It's not like one instant is totally different from the previous. And that there are simple laws governing how the previous snapshot relates to the next snapshot. Why isn't the universe simply white noise, like when you tune on a non-existent channel on old TV's and you get totally independent, random images at each instant.
kerkeslager 7y ago
> 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 7y ago
  > 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 no hypothesis presented, merely that there are deterministic factors that we don't know of. That's not a hypothesis. > 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). I think you are presenting a semantics argument that has little value. https://en.wikipedia.org/wiki/Uncertainty_principle https://en.wikipedia.org/wiki/Uncertainty_principle https://en.wikipedia.org/wiki/Quantum_fluctuation https://en.wikipedia.org/wiki/Quantum_fluctuation > the uncertainty principle actually states a fundamental property of quantum systems and is not a statement about the observational success of current technology Science doesn't work backwards from conclusions. If you think that there is determinism, there needs to be a testable theory that explains what these deterministic factors are. Like I said, we can simply attribute this supposed determinism to invisible unicorns and it'd be an equally valid explanation.
n4r9 7y ago
All experiments involving quantum theory affirm the mathematics, but are interpreted differently based on how one translates the mathematics into physical reality. For example, in Everettian interpretations there is no fundamental randomness. There is a universal wave function evolving continuously and deterministically, but decoherence processes lead to the appearance of randomness. In some Copenhagen type interpretations it only makes sense to talk about a wavefunction in the context of the system it describes, and there is a real physical collapse of the system's wavefunction which results in genuine fundamental randomness. Still other interpretations are agnostic about whether randomness is fundamental or merely apparent. No experiment to date has proved the supremacy of one class of these interpretations over the others.

homonculus1 7y ago

>Without subtle factors like air currents or imperfections in the pegs or the marbles, where does the marble land? If everything is truly perfect, it lands on the first peg.

computerex 7y ago
Does it fall to the left side of the peg, the right side, or does it stay on the peg?
- homonculus1 7y ago
  It comes to rest perfectly balanced on the peg. I intuit that the quantum effects are a wash on the macro scale, but maybe I'm talking out my ass.
  - computerex 7y ago
    What if the size of the peg is really tiny, let's say a few atoms and what if the marble was also very tiny, a single atom? What would happen then?
- deleted 7y ago
  [deleted]

jayd16 7y ago

But that is clearly the wrong reduction. Start position will determine the final position every time if we assume a perfect board. Marbles are not wave particles. You get a distribution based on the input distribution.

computerex 7y ago
It's a thought experiment. If we assume a perfect board with perfect marble with all other factors like imperfections/air currents removed and with the same initial position, and let's say the perfectly spherical marble hits the peg dead center every single time, does the marble fall to the left side of the peg or right or does it not fall to the either side?
- jayd16 7y ago
  Assuming it lands perfectly in the center, it rests, perfectly balanced on the peg.
  - computerex 7y ago
    What if the size of the peg is really tiny, let's say a few atoms and what if the marble was also very tiny, a single atom? What would happen then?
    - jayd16 7y ago
      I can assure you I don't know. That moves the problem from platonic shapes to real interactions of quantum particles. Atoms are not equivalent to perfect spheres.

criddell 7y ago

> Anyone can claim that there are deterministic causal factors leading to what appears to be randomness. What are those factors? What's the alternative? That something happens without a cause?

bonoboTP 7y ago
I mean, things could be that way. It's not so hard to imagine a universe where some events just happen without any causation or correlation with past events. The astonishing thing is that there is any causation at all! That events at different times are related to each other.
- criddell 7y ago
  You think a billiard ball that just starts moving for reasons of randomness is less astonishing than a billiard ball that moves because it was struck by another ball?
  - bonoboTP 7y ago
    Of course we are already used to things being that way. But a priori, order is what needs explanation, not orderlessness. The interesting thing is that there is movement. That there is temporal structure. It's not like one instant is totally different from the previous. And that there are simple laws governing how the previous snapshot relates to the next snapshot. Why isn't the universe simply white noise, like when you tune on a non-existent channel on old TV's and you get totally independent, random images at each instant.

kerkeslager 7y ago

> 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 7y ago
> 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 no hypothesis presented, merely that there are deterministic factors that we don't know of. That's not a hypothesis. > 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). I think you are presenting a semantics argument that has little value. https://en.wikipedia.org/wiki/Uncertainty_principle https://en.wikipedia.org/wiki/Uncertainty_principle https://en.wikipedia.org/wiki/Quantum_fluctuation https://en.wikipedia.org/wiki/Quantum_fluctuation > the uncertainty principle actually states a fundamental property of quantum systems and is not a statement about the observational success of current technology Science doesn't work backwards from conclusions. If you think that there is determinism, there needs to be a testable theory that explains what these deterministic factors are. Like I said, we can simply attribute this supposed determinism to invisible unicorns and it'd be an equally valid explanation.

n4r9 7y ago

All experiments involving quantum theory affirm the mathematics, but are interpreted differently based on how one translates the mathematics into physical reality. For example, in Everettian interpretations there is no fundamental randomness. There is a universal wave function evolving continuously and deterministically, but decoherence processes lead to the appearance of randomness. In some Copenhagen type interpretations it only makes sense to talk about a wavefunction in the context of the system it describes, and there is a real physical collapse of the system's wavefunction which results in genuine fundamental randomness. Still other interpretations are agnostic about whether randomness is fundamental or merely apparent. No experiment to date has proved the supremacy of one class of these interpretations over the others.