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My understanding is that the gravity detectors would not detect 10% or 90% of an electron. One would detect 0% and one would detect 100%. You cannot measure the

My understanding is that the gravity detectors would not detect 10% or 90% of an electron. One would detect 0% and one would detect 100%. You cannot measure the wave function directly. Attempting to do so collapses it. When that waveform collapse happens, everything about the quantum state collapses: electromagnetic field, gravity, etc.

rubidium 11y ago
Physics PhD here. You're correct. Any measurement of the electron state will affect the state. Grandparent did an excellent job setting up the hypothetical scenario by the way. It just turns out QM is awesomely weird like that. It does mean a mass which was de-localized by miles can, theoretically, localize to a single point instantly. However, any information about that localization is restricted to moving at the speed of light.
graycat 11y ago
Thanks. Sounds like when the wave function of the electron is moving, likely it is following the local geometry of space-time but otherwise is essentially lost to the universe. Then whenever we do detect a field, gravity, electro-magnetic, strong, weak, etc., necessarily we are detecting just collapsing wave functions, each of which happens at essentially just a point in time. Then after the point in time of the collapse, the electron is just a wave function again off on its way to another collapse. E.g., when an electron accelerates going around a circle and radiates photons, each photon radiated is from a collapse of the wave function of the electron at which time the electron creates a new wave function and continues on? Sounds like that. Hmm ... So, all we are seeing, feeling, detecting, observing, measuring, etc. are just high rate point processes of collapsing wave functions? Gads. Why didn't they tell me that back in high school? Where am I going wrong?
- joefkelley 11y ago
  You're getting closer. Regarding your electron-emitting-photons example: I would describe the photons being emitted as themselves in a quantum superposition of having been emitted/not emitted/emitted at different times, etc. It is when we detect or observe the photon that the state of the whole system collapses! The electron and the photon are entangled. Continue this line of thinking and you arrive at the famous Schrodinger's cat... it's a cascading entanglement of larger and larger groups of particles until you open the box and the waveform of every particle in the whole cat collapses to either alive or dead. The waveform is not really a physical object; I think of it as a probability distribution about the state of the system when observed. These probabilities can be highly correlated; in this case, the probability of observing the electron at one energy level or another is 100% correlated to the probability of observing or not observing the photon at all - which is the definition of entanglement. Yes, you are constantly observing collapsing wave functions. It might be some solace that most of said wave functions have highly-degenerate probability distributions. By this I mean that 99.999...% of the "mass" of the distribution lies in something reasonable happening. For example, each particle in a tennis ball is so highly entangled to every other particle, that when you throw it against a wall, it's exceedingly likely that the ball will bounce back. A single unentangled atom may have been able to pass right through the wall, but the tennis ball's "waveform" is much more stable and localized such that it's better approximated by classical mechanics.

rubidium 11y ago

Physics PhD here. You're correct. Any measurement of the electron state will affect the state. Grandparent did an excellent job setting up the hypothetical scenario by the way. It just turns out QM is awesomely weird like that. It does mean a mass which was de-localized by miles can, theoretically, localize to a single point instantly. However, any information about that localization is restricted to moving at the speed of light.

graycat 11y ago

Thanks. Sounds like when the wave function of the electron is moving, likely it is following the local geometry of space-time but otherwise is essentially lost to the universe. Then whenever we do detect a field, gravity, electro-magnetic, strong, weak, etc., necessarily we are detecting just collapsing wave functions, each of which happens at essentially just a point in time. Then after the point in time of the collapse, the electron is just a wave function again off on its way to another collapse. E.g., when an electron accelerates going around a circle and radiates photons, each photon radiated is from a collapse of the wave function of the electron at which time the electron creates a new wave function and continues on? Sounds like that. Hmm ... So, all we are seeing, feeling, detecting, observing, measuring, etc. are just high rate point processes of collapsing wave functions? Gads. Why didn't they tell me that back in high school? Where am I going wrong?

joefkelley 11y ago
You're getting closer. Regarding your electron-emitting-photons example: I would describe the photons being emitted as themselves in a quantum superposition of having been emitted/not emitted/emitted at different times, etc. It is when we detect or observe the photon that the state of the whole system collapses! The electron and the photon are entangled. Continue this line of thinking and you arrive at the famous Schrodinger's cat... it's a cascading entanglement of larger and larger groups of particles until you open the box and the waveform of every particle in the whole cat collapses to either alive or dead. The waveform is not really a physical object; I think of it as a probability distribution about the state of the system when observed. These probabilities can be highly correlated; in this case, the probability of observing the electron at one energy level or another is 100% correlated to the probability of observing or not observing the photon at all - which is the definition of entanglement. Yes, you are constantly observing collapsing wave functions. It might be some solace that most of said wave functions have highly-degenerate probability distributions. By this I mean that 99.999...% of the "mass" of the distribution lies in something reasonable happening. For example, each particle in a tennis ball is so highly entangled to every other particle, that when you throw it against a wall, it's exceedingly likely that the ball will bounce back. A single unentangled atom may have been able to pass right through the wall, but the tennis ball's "waveform" is much more stable and localized such that it's better approximated by classical mechanics.