Quantum Determinacy: Is Subatomic Event Cause Unknown or Uncertain?

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Discussion Overview

The discussion centers on the nature of subatomic events, particularly focusing on whether phenomena such as radioactive decay and photon emission are truly uncaused or if the lack of predictability stems from our current understanding. Participants explore the implications of quantum mechanics on determinism and causality at the subatomic level.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • One participant asserts that radioactive decay and similar events are uncaused, questioning whether this is a fundamental characteristic of the subatomic world or simply a reflection of our ignorance regarding the underlying processes.
  • Another participant mentions that while spontaneous photon emission occurs, stimulated emission introduces complexity, suggesting that there may be an undetermined cause behind these phenomena, reflecting Einstein's perspective.
  • A different viewpoint emphasizes that in quantum mechanics, events such as a light beam taking multiple paths to detectors lack a definitive cause, leading to unpredictability and challenging common intuitions about causality.
  • One participant discusses stimulated emission as a statistical process, noting that while it increases the likelihood of photon emission, it remains impossible to predict which specific atom will emit a photon at any given time.
  • Another participant highlights that the emission of photons is tied to electron excitation, yet emphasizes the inherent uncertainty in predicting these events, suggesting that this uncertainty is a fundamental aspect of the universe.

Areas of Agreement / Disagreement

Participants express differing views on whether subatomic events are truly uncaused or if the unpredictability is due to limitations in our understanding. There is no consensus on the nature of causality in quantum mechanics, and multiple competing perspectives are present.

Contextual Notes

The discussion reflects various interpretations of quantum mechanics and the implications for determinism and causality, with participants acknowledging the statistical nature of certain processes while debating the existence of underlying causes.

Darwin
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I have been told that radioactive decay, photon emission and absorption, and other such subatomic events are not deterministic. That besides leaving no clue as to when the event--say, decay--will take place, QM also has found that there IS NO initiating process that kicks off the event. In other words, decay events are uncaused. This, of course, goes beyond the mere inability to predict an event, but speaks to a very fundamental, and exceptionally unique character the subatomic world.

My question then, is: Are such events at the subatomic level, such as radioactive decay, truly without cause, or is it still simply a matter of we don't or can't know the cause?
 
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The 'S' in LASER stands for stimulated. I had always heard that, while sometimes an atom will emit a photon spontaneously, an atom can also be induced (or 'stimulated') to emit a photon. Still, that leaves an interesting class of phenomena that truly appear to be without an initiating process, as you put it. Einstein sure thought there was an as-yet undetermined underlying cause, but I think his point of view is a minority one among physicists.
 
All I can say is there is absolutely no reason for anything in the quantum world aside from what WE give it. So say a light beam takes two paths to two detectors before reaching only one and disappearing from the other. There was no reason for it to choose anyone path. This means there was no cause and we could not predict it. But why can't it always go down one path by being random instead of interchanging? This would mean that if it did go down one path all the time WE could predict it. There would be a cause (but there isn't one - we only think there is. So somehow by viewing which path the light went down meaning WE think the light went down causes the light to go down the other path just to contradict our meaningful observation such that we could not predict it, and there would then be no reason which would contradict our common sense.
 
Is Stimulated Emission Deterministic?

while sometimes an atom will emit a photon spontaneously, an atom can also be induced (or 'stimulated') to emit a photon.

If I understand correctly, this is also a statistical thing. Under the right conditions, the number of atoms that emit photons will be higher than you would normally expect, so we say that some fraction of the radiation is "stimulated". But I don't think you can point to one particular atom and say, 'that one radiated spontaneously', and 'that other one was stimulated'. You can't even predict beforehand which ones will emit at all.
 
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It is true that we cannot say when an atom will emit a photon, because it is a statistical process. However, the photons atoms emit stems from the excitation of electrons into higher "orbits". We can see if the atom has a free lower "orbit" and so it is a matter of time when the electrons jumps.

We cannot see on an atom if it was stimulated or spontaneously excited.

I firmly believe that this uncertainty is a truly fundamental part of our universe.
 

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