Do expand, please. It has been a while since I have studied this seriously. Do you have any examples of observations that don’t involve interacting with the system?
That’s not what I’m saying. My point is just that observation = interaction has a lot of implications. Particles are always interacting, so if the wave function represented some absolute state of a system, then the statement would just be incorrect because the wave function would be incapable of ever “spreading out” as it is constantly interacting with a lot of things yet we don’t “collapse” it in the mathematics until it interacts very specifically with us.
The only way it can be made consistent is to then say that wave functions are not absolute things but instead describe something relative to a particular system, sort of like how in Galilean relativity you need to specify a coordinate system to describe certain properties like velocity of systems. You pick a referent object as the “center” of the coordinate system which you describe other systems from that reference frame.
You would have to treat the wave function in a similar way, as something more coordinate than an actual entity. That would explain why it can differ between context frames (i.e. Wigner’s friend), and would explain why you have to “collapse” it when you interact with something, as the context would’ve changed so you would need to “zero” it again kinda like tarring a scale.
Often we leave out the referent object and it becomes implicit, such as if we say a car is traveling at 50 km/h, there is an implication here “relative to the earth.” That is implied so it doesn’t really need to be said, but people can become confused and think 50 km/h is really a property intrinsic to the car because we always leave it out.
That’s where a lot of confusion in QM comes from: we usually are concerned with what we will observe ourselves, what will actually show up on our measuring devices, so we implicitly use ourselves and our measuring devices as the referent object and by extension forget that we are describing properties of things relative to a particular coordinate system and not absolute.
AHH, I think I see what you have misunderstood. I am not saying all interactions are observations, rather that observations are a subset of interactions, hence uncertainty.
Furthermore I think it would be more useful to say that the wave function only collapses when it is actually necessary to the interaction rather than when it interacts with ‘us’. Unless you can provide a counterexample. Privileging observations made by humans reeks of mysticism in my opinion and is the cause of a lot of the misunderstandings about quantum physics among laypeople.
Saying that observations are a special kind of interaction does seem to be privileging humans, though? What is different from measurements/observations and any other interaction?
I’m neutral on the subject of if there are non-observational interactions. Though I ask again, are you aware of any observations that do not involve interactions?
Edit: I should also point out, that I don’t believe an observation necessarily requires a human, mind, or intelligence.
Why do you keep asking that? I already explained I’m not claiming observations = no interactions in extensive detail and you turn around and ask me that gain.
Because you seem to have a problem with me saying that all observations are interactions.
Futher, if it is true that if observations are interactions, then RQM must be true, surely it goes from a fringe interpretation to just simple fact unless you can find a counterexample?
At this point, I’m not even sure I quite see what your point is supposed to be.
I think you are just trying to fight rather than actually have a discussion so I’m not really interested in going on, but I will say one last thing to clarify what I am saying for other people who might be reading.
If you say observation = interaction then this inherently leads you to RQM which is like the definition of the interpretation. As I said at the beginning, I do support this interpretation, I think it’s the most reasonable approach, but it should be made clear this is a rather fringe point of view and not supported by most academics. You can see in the paper below only 6% of academics support it. And you clearly don’t seem to support it yourself as you seem to be pushing back against that rather than just agreeing with my statement it is the most intuitive way to think about things.
The plurality there support the Copenhagen view where observation really is given a special role.
Without going the route of RQM then you end up with something that is just objectively false as the wave function would be incapable of spreading out since particles are always interacting with things, rendering quantum phenomena impossible.
You can clarify instead by saying observation → interaction, that is to say, an observation implies an interaction, i.e. it inherently always entails an interaction but not interactions are observations, however, if you do this, you end up with the measurement problem. That is to say, you need to actually construct a theory to account for what kinds of interactions actually qualify as a measurement/observation. To quote John Bell…
What exactly qualifies some physical systems to play the role of ‘measurer’? Was the wavefunction of the world waiting to jump for thousands of millions of years until a single-celled living creature appeared? Or did it have to wait a little longer, for some better qualified system . . . with a PhD?
Specifying a theory of measurement is known as an “objective collapse” model and they make different predictions than traditional quantum mechanics because depending on where you set the threshold for what kind of interaction qualifies as an “observation” changes how much the wave function can spread out before being collapsed again by such an “observation.”
There are several models of this like the Ghirardi–Rimini–Weber theory and the Diósi–Penrose model but these are ultimately more than just other interpretations of quantum mechanics but ultimately entirely new theories.
It is not so simple just to say “observation is an interaction” and then pretend like the job is done, or else there would be no confusion in interpreting quantum mechanics at all. There is a lot more clarification that has to be made in order for it to make sense.
Do expand, please. It has been a while since I have studied this seriously. Do you have any examples of observations that don’t involve interacting with the system?
That’s not what I’m saying. My point is just that observation = interaction has a lot of implications. Particles are always interacting, so if the wave function represented some absolute state of a system, then the statement would just be incorrect because the wave function would be incapable of ever “spreading out” as it is constantly interacting with a lot of things yet we don’t “collapse” it in the mathematics until it interacts very specifically with us.
The only way it can be made consistent is to then say that wave functions are not absolute things but instead describe something relative to a particular system, sort of like how in Galilean relativity you need to specify a coordinate system to describe certain properties like velocity of systems. You pick a referent object as the “center” of the coordinate system which you describe other systems from that reference frame.
You would have to treat the wave function in a similar way, as something more coordinate than an actual entity. That would explain why it can differ between context frames (i.e. Wigner’s friend), and would explain why you have to “collapse” it when you interact with something, as the context would’ve changed so you would need to “zero” it again kinda like tarring a scale.
Often we leave out the referent object and it becomes implicit, such as if we say a car is traveling at 50 km/h, there is an implication here “relative to the earth.” That is implied so it doesn’t really need to be said, but people can become confused and think 50 km/h is really a property intrinsic to the car because we always leave it out.
That’s where a lot of confusion in QM comes from: we usually are concerned with what we will observe ourselves, what will actually show up on our measuring devices, so we implicitly use ourselves and our measuring devices as the referent object and by extension forget that we are describing properties of things relative to a particular coordinate system and not absolute.
AHH, I think I see what you have misunderstood. I am not saying all interactions are observations, rather that observations are a subset of interactions, hence uncertainty.
Furthermore I think it would be more useful to say that the wave function only collapses when it is actually necessary to the interaction rather than when it interacts with ‘us’. Unless you can provide a counterexample. Privileging observations made by humans reeks of mysticism in my opinion and is the cause of a lot of the misunderstandings about quantum physics among laypeople.
Saying that observations are a special kind of interaction does seem to be privileging humans, though? What is different from measurements/observations and any other interaction?
I’m neutral on the subject of if there are non-observational interactions. Though I ask again, are you aware of any observations that do not involve interactions?
Edit: I should also point out, that I don’t believe an observation necessarily requires a human, mind, or intelligence.
Why do you keep asking that? I already explained I’m not claiming observations = no interactions in extensive detail and you turn around and ask me that gain.
Because you seem to have a problem with me saying that all observations are interactions.
Futher, if it is true that if observations are interactions, then RQM must be true, surely it goes from a fringe interpretation to just simple fact unless you can find a counterexample?
At this point, I’m not even sure I quite see what your point is supposed to be.
I think you are just trying to fight rather than actually have a discussion so I’m not really interested in going on, but I will say one last thing to clarify what I am saying for other people who might be reading.
If you say observation = interaction then this inherently leads you to RQM which is like the definition of the interpretation. As I said at the beginning, I do support this interpretation, I think it’s the most reasonable approach, but it should be made clear this is a rather fringe point of view and not supported by most academics. You can see in the paper below only 6% of academics support it. And you clearly don’t seem to support it yourself as you seem to be pushing back against that rather than just agreeing with my statement it is the most intuitive way to think about things.
https://arxiv.org/abs/1301.1069
The plurality there support the Copenhagen view where observation really is given a special role.
Without going the route of RQM then you end up with something that is just objectively false as the wave function would be incapable of spreading out since particles are always interacting with things, rendering quantum phenomena impossible.
You can clarify instead by saying observation → interaction, that is to say, an observation implies an interaction, i.e. it inherently always entails an interaction but not interactions are observations, however, if you do this, you end up with the measurement problem. That is to say, you need to actually construct a theory to account for what kinds of interactions actually qualify as a measurement/observation. To quote John Bell…
https://philpapers.org/rec/BELAM
Specifying a theory of measurement is known as an “objective collapse” model and they make different predictions than traditional quantum mechanics because depending on where you set the threshold for what kind of interaction qualifies as an “observation” changes how much the wave function can spread out before being collapsed again by such an “observation.”
There are several models of this like the Ghirardi–Rimini–Weber theory and the Diósi–Penrose model but these are ultimately more than just other interpretations of quantum mechanics but ultimately entirely new theories.
It is not so simple just to say “observation is an interaction” and then pretend like the job is done, or else there would be no confusion in interpreting quantum mechanics at all. There is a lot more clarification that has to be made in order for it to make sense.