It’s been forever since I learned about this experiment in school. How TF did they measure the unobserved state, since measuring is an observation? Was it indirect measuring?
You don’t! You observe the result.
When no interaction happens the resulting pattern is described well with wave functions.
If interaction happens to determine which slit it is traveling through the double line result is seen and can be described by mechanical functions.
This “we have math for both results” for interpreted to “has properties of both wave and particle”.
Which I guess was one press release away from n"it’s both and depends on if I’m looking!"
The film on which the interference pattern is made is, in a sense, an observer. But the observer that most people mean is what was added after the wave-like interference pattern made researchers ask “okay, but which slit did the electron go through?” and they put a detector near the slits to determine an answer to that. When they did this, the wave function collapsed and the film no longer showed an interference pattern, but two bands, which would correspond to an particle-like electron going through either one slit or the other.
Basically the sensor is interacting with the quantum particle by measuring where it is before the slit. This collapses the wave function of the particle, causing it to appear at one point in space. Since the particle is collapsed to a point before the slit, it travels through only one of the slits and impacts the screen. Since it is just a single point particle now, there is no wave to interfere with the particle and create multi-line wave pattern, so we just see two straight lines on the screen that match up with the slits.
The sensor performing the measurement is the observer in this case. No living creature is needed to observe the particle to make it collapse. It’s simply just, quantum particles are just wave functions up until the point that they have to collapse to a particle because it has interacted with something (a screen or a sensor or anything). That is about the limit of my understanding at least
Yes, that’s exactly what happens. Nobody has to check what it actually measured.
That’s what they did with the same experiment in a closed box where they just increased the temperature. In that case air molecules just acted as the “sensor” and collapsed the wave.
I’m not a physicist, so I’m unfamiliar with the particulars of how the detectors used work, but as I understand it, possible explanations like the one you suggest were initially considered as more likely than what was actually documented, but that’s where replicability helps out — if one research group observes something baffling that flies in the face of what is understood to be true, then maybe that’s an equipment or experimenter error. Not so much when a particular result has been demonstrated in countless different ways by many researchers, and when theories built to explain the weird stuff have predictive power for other, related phenomena.
Speaking of stuff that quantum mechanics helps us to understand, there are a few really cool examples of where quantum phenomena is relevant in my field of science (biochemistry), I’ll have a look to see if I can find the thing I’m thinking of.
It’s been forever since I learned about this experiment in school. How TF did they measure the unobserved state, since measuring is an observation? Was it indirect measuring?
You don’t! You observe the result. When no interaction happens the resulting pattern is described well with wave functions. If interaction happens to determine which slit it is traveling through the double line result is seen and can be described by mechanical functions.
This “we have math for both results” for interpreted to “has properties of both wave and particle”. Which I guess was one press release away from n"it’s both and depends on if I’m looking!"
The film on which the interference pattern is made is, in a sense, an observer. But the observer that most people mean is what was added after the wave-like interference pattern made researchers ask “okay, but which slit did the electron go through?” and they put a detector near the slits to determine an answer to that. When they did this, the wave function collapsed and the film no longer showed an interference pattern, but two bands, which would correspond to an particle-like electron going through either one slit or the other.
Could the whole thing be misconstrued, and just the proximity of the sensor be what is causing the wave collapse, not the observation?
Basically the sensor is interacting with the quantum particle by measuring where it is before the slit. This collapses the wave function of the particle, causing it to appear at one point in space. Since the particle is collapsed to a point before the slit, it travels through only one of the slits and impacts the screen. Since it is just a single point particle now, there is no wave to interfere with the particle and create multi-line wave pattern, so we just see two straight lines on the screen that match up with the slits.
The sensor performing the measurement is the observer in this case. No living creature is needed to observe the particle to make it collapse. It’s simply just, quantum particles are just wave functions up until the point that they have to collapse to a particle because it has interacted with something (a screen or a sensor or anything). That is about the limit of my understanding at least
Yes, that’s exactly what happens. Nobody has to check what it actually measured.
That’s what they did with the same experiment in a closed box where they just increased the temperature. In that case air molecules just acted as the “sensor” and collapsed the wave.
I’m not a physicist, so I’m unfamiliar with the particulars of how the detectors used work, but as I understand it, possible explanations like the one you suggest were initially considered as more likely than what was actually documented, but that’s where replicability helps out — if one research group observes something baffling that flies in the face of what is understood to be true, then maybe that’s an equipment or experimenter error. Not so much when a particular result has been demonstrated in countless different ways by many researchers, and when theories built to explain the weird stuff have predictive power for other, related phenomena.
Speaking of stuff that quantum mechanics helps us to understand, there are a few really cool examples of where quantum phenomena is relevant in my field of science (biochemistry), I’ll have a look to see if I can find the thing I’m thinking of.
Oh yes, I suppose they could just place non measuring equipment near the slit and run the test again.