What does quantum theory really say?

In the Kalam Cosmological argument thread, Cavediver expressed the opinion that my list of effects that have no cause does not reflect the most recent perspectives on quantum theory. For reference, here's my list:

1. Nothing causes a particular atom of Uranium-238 to decay at a particular time. It just happens.
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2. Nothing causes a particular electron to tunnel through the barrier of a tunnel diode. It just happens.
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3. Nothing causes an entangled particle's wave function to collapse to either up or down spin upon being observed. It just happens.
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4. Virtual particles. There is nothing that causes them to flit into existence. They just do, governed by the laws of quantum physics.
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5. Which slit a particle travels through in diffraction experiments.

Cavediver's position, as nearly as I can understand it, seems to be that these effects do have causes because decoherence is a deterministic process. My reply is that while decoherence may be deterministic, which state anything in my list eventually decoheres to is non-deterministic. In other words, nothing in my list has anything to do with decoherence. The list only relates to the end result of decoherence.An analogy from the classical world might be that if you throw a baseball through a window it is deterministic that the glass will break, but how it splits up into pieces and where those pieces end up is random and non-deterministic. (I understand that in the classical world these things are theoretically knowable. This is only an analogy, an attempt to make clear my viewpoint by reference to something familiar. It is not a claim that a breaking window is the same thing as decoherence.)Cavediver's response to my inquiry about how he would predict when a uranium atom would decay was something along the lines of "Heck if I know", which seems to concede my point, but he then continued arguing that these effects are deterministic and likely have a cause. His perspective struck me as counter to all the popularizations I've read in books and magazines, and I said so. Cavediver's reply was that attempting to draw conclusions from a layperson's level understanding of quantum theory can often result in nonsense, but I'm not extrapolating on my meager quantum knowledge. I'm merely attempting to regurgitate what I've read, which starkly contradicts Cavediver's claims of what quantum theory really says.I suggested to Cavediver that he start a thread if he wanted to pursue this issue, and I had no intention of starting the thread myself, but I've been reading Decoding the Universe by Charles Seife the past couple weeks, and tonight while reading chapter 7 I came across this on pages 205-206 relevant to the item in my list about virtual particles: Cavediver has a different view, and he expresses it in Message 165: So we can start the discussion of my list here. Are virtual particles real or not?I guess I'll conclude by saying that to me Cavediver's position about popularizations of quantum theory seems to be that they are so bad as to be in the class of "storks bring babies" explanations, mere fairy tales having little correspondence to reality. I can accept that simplified explanations can be misleading, but find it hard to accept that they would, in the aggregate, make glaringly false statements.--Percy

Thread moved here from the Proposed New Topics forum.

To make a claim of non-determinism, you need a mechanism. The mechanism usually cited is that of "collapse". "collapse" is not necessarily involved, and may not exist: it is the convenient Copenhagen Interpretation of what is going on. Decoherence is one possible way you get to these end results, as opposed to the mysterious CI which involves a non-deterministic collapse. You are just describing the Copenhagen Interpretation. Percy, please avoid the quote-mining. I also said that I do not know how to calculate outcomes through complex or chaotic systems (coin tossing, ocean dynamics)... is this proof that they are non-deterministic? Percy, I will gladly join in a discussion if there is one and answer questions, but why would I start a thread to push the ideas of modern physics in some random area? There are many other areas of physics that I would present before this if I had the time and the inclination to just spout physics.

quote:

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Particles are constantly winking in and out of existence...These particles constantly bump into things...These evanescent particles exist, we can even see the effects they have...Once in a while, one of these evanescent particles bumps into the nucleus, makes a measurement, and transmits that information into the environment.

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Layman-talk at its worst Try the Wikipedia entry on Virtual Particles. There seem to be some grad students trying to keep it in line, and have done a half decent job. The introduction is as I would say it. The page discussion is also interesting.

This is as much an unsupported assertion as the other thread's OP that asserts that every effect has a cause.I would argue the exact opposite. There is not, as far as we can tell, any mechanism controlling the choice of state when a quantum superposition decoheres. From my perspective you seem to be arguing against quantum uncertainty itself. If decoherence defines a deterministic method for figuring out which state a superposition will decohere to, then what is it? I didn't start this thread so I could be handed reading assignments, and the Forum Guidelines specifically discourage this approach. If you'd like to attempt a layperson-level explanation of how my list of uncaused effects actually have causes, then I'm listening.--Percy

Forget it Percy. I am not interested in discussing anything with anyone not interested in learning.

Let the record show that Cavediver is uninterested in discussing the issue within the framework of this discussion board's Forum Guidelines.--Percy