8 ms·

It seems that can't be true, because if you randomly decide after the particle is launched whether to measure it or not, the interference pattern still appears.

by raylad 5y ago

It seems that can't be true, because if you randomly decide after the particle is launched whether to measure it or not, the interference pattern still appears. So it's not the measuring that does anything in superdeterminism apaprently, it's that if you do measure it, that was "known" in advance by the state of the universe. If not that, what is supposed to be going on (physicists please respond).

rafaelero 5y ago
> if you randomly decide after the particle is launched whether to measure it or not, the interference pattern still appears. So, if you run an experiment and in 50% of the time the machine measures the particles and in 50% don't, does it still form an interference pattern in both cases? That does seem odd. I would expect that whenever a measurement is made, the interference pattern would disappear.
- lmm 5y ago
  It forms a weaker interference pattern - imagine superimposing 50% of the interference pattern and 50% of the non-interfering look. There's also the fun of the delayed-choice quantum eraser experiment, where if you measure (or not) which slit the photon went through after measuring the interference pattern (or not), you see (or don't see) the interference pattern.
  - rafaelero 5y ago
    Ok, that's definitely not what OP said. Of course the particle still can interfere with itself after the slit, it's just that when the measurement is made, the pattern of two waves interfering gets much weaker/non-existent. Also, the experiment you are alluding to does not say what you think it says. Perhaps you will be interested on another video from Sabine. https://www.youtube.com/watch?v=RQv5CVELG3U&ab_channel=SabineHossenfelder https://www.youtube.com/watch?v=RQv5CVELG3U&ab_channel=Sabin...
    - lmm 5y ago
      I don't/can't watch videos. I'll happily look at something written, but frankly "the experiment you are alluding to does not say what you think it says" does not convince me that you know what you're talking about and are looking to find the truth. I have a master's in this stuff and I'm pretty sure what I said is a fair description of the experiment in question; if you think something is different about it then be specific.
      - rafaelero 5y ago
        You can read the transcription. Sean Carrol also wrote about it too https://www.preposterousuniverse.com/blog/2019/09/21/the-notorious-delayed-choice-quantum-eraser/ https://www.preposterousuniverse.com/blog/2019/09/21/the-not...
        lmm 5y ago
        I agree with the article you've linked (although the graphs are either mislabelled or being used to illustrate a different experiment from the one they're actually taken from; in the Kim et al setup R03 is not R01 + R02, it's a measurement from a different detector). How do you think it contradicts what I said?

by raylad 5y ago

rafaelero 5y ago

> if you randomly decide after the particle is launched whether to measure it or not, the interference pattern still appears. So, if you run an experiment and in 50% of the time the machine measures the particles and in 50% don't, does it still form an interference pattern in both cases? That does seem odd. I would expect that whenever a measurement is made, the interference pattern would disappear.

lmm 5y ago
It forms a weaker interference pattern - imagine superimposing 50% of the interference pattern and 50% of the non-interfering look. There's also the fun of the delayed-choice quantum eraser experiment, where if you measure (or not) which slit the photon went through after measuring the interference pattern (or not), you see (or don't see) the interference pattern.
- rafaelero 5y ago
  Ok, that's definitely not what OP said. Of course the particle still can interfere with itself after the slit, it's just that when the measurement is made, the pattern of two waves interfering gets much weaker/non-existent. Also, the experiment you are alluding to does not say what you think it says. Perhaps you will be interested on another video from Sabine. https://www.youtube.com/watch?v=RQv5CVELG3U&ab_channel=SabineHossenfelder https://www.youtube.com/watch?v=RQv5CVELG3U&ab_channel=Sabin...
  - lmm 5y ago
    I don't/can't watch videos. I'll happily look at something written, but frankly "the experiment you are alluding to does not say what you think it says" does not convince me that you know what you're talking about and are looking to find the truth. I have a master's in this stuff and I'm pretty sure what I said is a fair description of the experiment in question; if you think something is different about it then be specific.
    - rafaelero 5y ago
      You can read the transcription. Sean Carrol also wrote about it too https://www.preposterousuniverse.com/blog/2019/09/21/the-notorious-delayed-choice-quantum-eraser/ https://www.preposterousuniverse.com/blog/2019/09/21/the-not...
      - lmm 5y ago
        I agree with the article you've linked (although the graphs are either mislabelled or being used to illustrate a different experiment from the one they're actually taken from; in the Kim et al setup R03 is not R01 + R02, it's a measurement from a different detector). How do you think it contradicts what I said?