Friday, December 6, 2019

Believe this vision of the world religiously

Physicist Chris Fuchs says in a Discover mag interview:
You’ve written critically about the Many Worlds (or Everettian) Interpretation of quantum mechanics. What are its main shortcomings?

Its main shortcoming is simply this: The interpretation is completely contentless. I am not exaggerating or trying to be rhetorical. It is not that the interpretation is too hard to believe or too nonintuitive or too outlandish for physicists to handle the truth (remember the movie A Few Good Men?). It is just that the interpretation actually does not say anything whatsoever about reality. I say this despite all the fluff of the science-writing press and a few otherwise reputable physicists, like Sean Carroll, who seem to believe this vision of the world religiously.

For me, the most important point is that the interpretation depends upon no particular or actual detail of the mathematics of quantum theory. No detail that is, except possibly on an erroneous analysis of the meaning of “quantum measurement” introduced by John von Neumann in the 1930s, which is based on a reading of quantum states as if they are states of reality. Some interpretations of quantum theory, such as the one known as QBism, reject that analysis. ..

The Many Worlds Interpretation just boils down to this: Whenever a coin is tossed (or any process occurs) the world splits. But who would know the difference if that were not true? What does this vision have to do with any of the details of physics? ..

You also object to the idea of multiple alternate worlds on a philosophical level, correct?

Depending in no way on the details of quantum theory, the Many Worlds Interpretation has always seemed to me as more of a comforting religion than anything else. It takes away human responsibility for anything happening in the world in the same way that a completely fatalistic, deterministic universe does, though it purportedly saves the appearance of quantum physics by having indeterministic chance in the branches.
I have been saying similar things here for years. I quit calling Many-Worlds an interpretation, because it is not even that. It doesn't even make any predictions. As he says, there is no content to it.

1 comment:

  1. Roger,
    I do not question that the mathematics of quantum mechanics can be useful for making certain predictions that have application, I do think they are rubbish as a mechanism by which any thing can actually happen, much as epicycles has utility in some predictive regards but are utter rubbish as an actual mechanism by which orbits physically function.

    I do question any physical theory that is based entirely on hypostatization (math hand waving) as a MECHANISM by which anything functions.

    Math is not physics. Numbers are not reality, they are abstraction. You can euphemistically apply numbers like labels to actual things... but there must always always always being some 'thing' that is represented by those numbers, or you aren't measuring anything. Presently, quantum mechanics is largely dependent upon an interpretation that proclaims 'you can't know what is going on, don't try to understand, just do the math and accept it'. I reject this premise entirely in any scientific regard.

    There is ALWAYS a mechanism. You may not have any idea what it is, and substitute a temporary placeholder, but the placeholder is not a mechanism (or an answer).

    You enjoy talking about waves, often invoking them in lieu of particles. I reject this kind of talk merely because 'wave/s' is a movement of something, and the 'something' is being epistemically removed from the discussion. For a change, let us try instead to understand what a wave actually is in reality, and how it has physical properties that can interact in ways that remove the need for 'many worlds' or any other non physical mathematical blather passing itself of as physics.

    Take a look at a simple physical demonstration. Then take a good think about this might mean about the interpretation of the double slit experiment.

    Waves are properties of something actual (not numbers) moving a particular way, not abstractions floating in arithmatic fantasy. The popular double slit experiment interpretation is nothing but a sleight of hand, it diverts you from the important question, How do waves of something interact with gaps in a particular material? Also remember that in the popular interpretation, the slit is always treated as a solid impermeable barrier, and the waves of (????) are treated as an immaterial mathematical probability, both of which are inaccurate, and neither of which has any way to interact with the other.