Free will?

[atanu]

QM doesn't suggest non-local anything; that would break Relativity.

To me the above statement of friend PolyHedra settled the whole issue.

 

[idav]

And it is now dated (also, it has everything to do with Schroedinger's cat, and neither Bohr, nor Dirac, nor Feynmann changed this, as the "superposition" and "vanishing h" was the method introduced primarily by Bohr to explain why quantum processes like superposition states "disappear" at the macroscopic level) :
"Despite their successes, QM and GTR are beset by problems that raise worries about the foundations of these theories—QM by the measurement problem and associated problems of non-locality, GTR by the problems that are the focus of this study. Some physicists harbor the hope that both sets of problems will be resolved by the sought-after quantum theory of gravity. It is difficult to assess this hope since we can now only dimly perceive the shape that a successful marriage of QM and GTR will take. And even if the hope is eventually realized, it is important to pursue these foundational problems for the light they may shed on the correct path towards the marriage.
For many purposes, the measurement problem in QM can be ignored by experimentalists and theoreticians alike. Not surprisingly, it was ignored by a large segment of the physics community, and the opinion was once widespread that this problem is merely a Scheinproblem. I vividly recall the occasion of a lecture on the measurement problem given in the early 1970s at The Rockefeller University by a Nobel laureate in physics. The reaction of the audience, composed largely of theoretical physicists and mathematicians, was distinctly cool if not unfriendly. The skepticism was directed not so much at the proposed solution as to the notion that there was a problem to be solved. After the lecture, the laureate remarked ruefully: "I suppose that I will have to do something new to restore my reputation." Today his lecture would likely get a different reception, at least judging from the fact that The Physical Review, the most prestigious journal in theoretical physics, now routinely publishes articles on this topic. The implied change in attitude reflects a recognition that the measurement problem poses a fundamental challenge for QM, although how to state the challenge is controversial. On the one hand, the problem can be seen as revealing that there is something rotten at the core of the theory because of its inability to give a satisfactory description of what occurs in the interaction between an object system and a measurement apparatus."

That was all the way back in '95, from Earman's Bangs, Crunches, Whimpers, and Shrieks: Singularities and Acausalities in Relativistic Spacetimes (Oxford University Press). In case you're wondering, that was after Feynmann, and the situatation hasn't improved. It's gotten worse.

Yet even with Schrodinger's cat there are still limits. Regardless of the cat being alive and dead at the same time it isn't reality. The reality is you will find the cat either alive or dead and not both, which means even though the principle of QM allows for both our reality only allows for one. Same with the slit experiments. It acts as if it is in many places at once but the actual photon will only land in one place on the screen which spells out the classical limitation of even particles in a quantum state.

 

[PolyHedral]

Yet even with Schrodinger's cat there are still limits. Regardless of the cat being alive and dead at the same time it isn't reality. The reality is you will find the cat either alive or dead and not both, which means even though the principle of QM allows for both our reality only allows for one. Same with the slit experiments. It acts as if it is in many places at once but the actual photon will only land in one place on the screen which spells out the classical limitation of even particles in a quantum state.

As theory dictates, the observer becomes entangled with the cat/photon's superposition. This doesn't necessarily mean the superposition isn't there anymore.

 

[idav]

As theory dictates, the observer becomes entangled with the cat/photon's superposition. This doesn't necessarily mean the superposition isn't there anymore.

I suppose that is true but not observably true. We observe the reality of the situation.

 

[PolyHedral]

I suppose that is true but not observably true. We observe the reality of the situation.

The theory dictates that observations irrevocably change the reality, and also interfere with and invalidate each other.

 

[idav]

The theory dictates that observations irrevocably change the reality, and also interfere with and invalidate each other.

It would appear to change the reality but I'd chalk that up to a misinterpretation of what is being observed and possibly missing knowledge.

 

[PolyHedral]

It would appear to change the reality but I'd chalk that up to a misinterpretation of what is being observed and possibly missing knowledge.

There is no missing knowledge involved, unless you want to usurp literally all of quantum mechanics. No amount of information will let you bypass the uncertainty principle, or the fact that certain observables aren't compatible with each other.

 

[idav]

There is no missing knowledge involved, unless you want to usurp literally all of quantum mechanics. No amount of information will let you bypass the uncertainty principle, or the fact that certain observables aren't compatible with each other.

Unpredictable doesn't mean it doesn't follow only one casual chain. Nobody can predict the lottery accurately either but doesn't mean it defies physics it means there are too many unknown variables.

 

[PolyHedral]

Unpredictable doesn't mean it doesn't follow only one casual chain. Nobody can predict the lottery accurately either but doesn't mean it defies physics it means there are too many unknown variables.

The logic being used here is not, "The universe is unpredictable, therefore quantum is indeterministic." It is the reverse: the theory tells us that observed quantities are inherently, always indeterministic, and therefore the universe is unpredictable on the lowest level.

 

[LegionOnomaMoi]

Yet even with Schrodinger's cat there are still limits.

The limits are the problem. What are they, and where? Because this:

Regardless of the cat being alive and dead at the same time it isn't reality.

is the opposite of what Schroedinger's thought experiment is about. If we were less humane, and could set up a sufficiently isolated system, we may indeed be able to create the box in which a trigger of poison is described by a superposition state of being both decayed and not decayed. One state releases the poison, the other does not. Which means that one state ensures the cat is dead, and the other does not. Which means that the cat is, in reality, both alive and dead.

The fact that opening the box makes it appear that the cat was only always either dead or alive just makes things worse, not better. It doesn't suddenly make "reality" clear. The reality was that the cat was both alive and dead, at the same time, but we couldn't "see" this.

Nor does Everett's solution, and further work on his approach, resolve anything (italics in original):
"The central idea of relative-state interpretations, first described (but not worked out in detail) by Hugh Everett in the late 1950s and subsequently further developed by many authors, is to abandon this system–observer duality. Instead, one (i) assumes the existence of a total quantum state |psi> representing the physical state of the entire universe and (ii) upholds the universal validity of the Schroedinger evolution. In addition, one (iii) postulates that at the completion of a measurement all terms in the expansion of the total state in the eigenbasis of the measured observable correspond to (physical) states in some sense, that is, no particular “outcome” is singled out, neither formally nor physically. Each of these (physical) states can be understood as relative (a) to the state of the other part in the composite system (as in Everett’s original proposal), (b) to a particular “branch” of a constantly “splitting” universe (the many-worlds interpretation, popularized by DeWitt and Deutsch), or (c) to a particular “mind” in the set of minds of the conscious observer (the many-minds interpretation).
Relative-state interpretations face two main difficulties. First, the preferred-basis problem: If states are only relative, the question arises, relative to what? What determines the particular basis terms that are used to define the branches, which in turn specify the relative properties, worlds, or minds in the next instant of time? When precisely does the “splitting” occur? Which properties are made determinate in each branch, and how are they connected to the determinate properties of our experience? Second, what is the meaning of probabilities, given that every possible outcome “occurs” in some sense, and how can Born’s rule be motivated in such an interpretive framework?" p. 336 of Decoherence and the Quantum-to-Classical Transition (The Frontiers Collection).

The idea behind this was even more radical than the so-called Copenhagen interpretation. Instead of having a subatomic reality which exhibited all the quantum weirdness, but only at the unobservable level, all reality is this "weirdness". The problem is that this was an attempt to resolve a particular mathematical result which was itself derived from and motivated within an entirely different theoretical framework incompatible with the new interpretation. By making the math be as much "take it like you derive it" as possible, we still don't get anywhere, because it can only be meaningful without the experimental basis for the mathematical formalisms we use to begin with along with throwing out any usefulness of any measurement. Because we aren't measuring anymore, but "singling" out particular outcomes from the possible outcomes in a way we can't explain and at a time we can't explain (that is, when exactly does the "splitting" occur?). And when we now talk about the states of the "system" even before "measurement", we have no basis for doing so, because the "states" in the math are still determined by the older theoretical framework and (more importantly) the way the experiment is set up quite apart from any actual quantum states. We can even arbitrarily decide to change the math a bit, but run the same experiment, and supposedly this now changes reality? If so, how, when, and why?

The reality is you will find the cat either alive or dead and not both, which means even though the principle of QM allows for both our reality only allows for one.

QM is supposed to describe "our" reality. Or reality period, and if this means that what we perceive as being real is fundamentally different from the nature of the cosmos (e.g., we are constantly splitting universes here), phyiscs is still supposed to explain how what we perceive can be derived from theory and experiment shows. It can't (at least now), and there's isn't even an agreed upon way to understand exactly what the problem is (simply that there is a fundamental one), let alone a solution. Nor can we just do what was tried for some time, and just "go where the math leads":
"Many decades have now elapsed since the famous Solvay conference of 1927 during which the elite of physicists engaged in a heated debate about the interpretation of quantum mechanics. Yet, discussions about the meaning of quantum theory show no sign of abating. If one would like to go beyond a purely pragmatic “shut-up-and-calculate” approach to quantum mechanics and relate the quantum formalism to a presumed physical reality “out there,” it is virtually impossible not to get tangled up in interpretive questions. The existence of a variety of interpretations of quantum mechanics is therefore as old as quantum theory itself." (ibid)

It acts as if it is in many places at once but the actual photon will only land in one place on the screen which spells out the classical limitation of even particles in a quantum state.

What "actual photon", and how can it "act" as if it is in many places at once when it isn't, and how does this "classical limitation" (which is just another way of saying "what we get depends on when we destroy the quantum system") tell us that there is an "actual photon"?

 

[idav]

The logic being used here is not, "The universe is unpredictable, therefore quantum is indeterministic." It is the reverse: the theory tells us that observed quantities are inherently, always indeterministic, and therefore the universe is unpredictable on the lowest level.

Unpredictable to what extent. We don't know where a virtual particle will pop out of nowhere? Something must be missing, it comes from somewhere.

What "actual photon", and how can it "act" as if it is in many places at once when it isn't, and how does this "classical limitation" (which is just another way of saying "what we get depends on when we destroy the quantum system") tell us that there is an "actual photon"?

There is an actual photon (particle), that they see and put into a projectile and blast it at a screen using laws of velocity and reactions have opposite reactions etc. I've noted before that the photons are going through walls, they bounce and reflect and go through slits. When is there not an actual photon is when it is just a quantum effect, which is really just dependent on the energy state of the particle in question.

 

[PolyHedral]

Unpredictable to what extent. We don't know where a virtual particle will pop out of nowhere? Something must be missing, it comes from somewhere.

AFAIK, a given particle's wavefunction has a non-zero magnitude (i.e. non-zero probability of being found there) everywhere that has equal or less energy than the particle. This includes the other side of the universe - the probability of being found there is just very small.

 

[Thief]

And Whose will makes it so?
We are in the science and religion section.

And leaving the will of God out of it?

 

[Gjallarhorn]

And Whose will makes it so?
We are in the science and religion section.

And leaving the will of God out of it?

Well, if you'd like to bring God into it, it's determined. And done.

 

[LegionOnomaMoi]

There is an actual photon (particle), that they see and put into a projectile and blast it at a screen using laws of velocity and reactions have opposite reactions etc. I've noted before that the photons are going through walls, they bounce and reflect and go through slits. When is there not an actual photon is when it is just a quantum effect, which is really just dependent on the energy state of the particle in question.

How do you know there is an "actual photon" or subatomic particle? They don't actually load up a some "quantum cannon" with individual particles. For the double-slit experiment, we have instruments that allow us to take something like light in the form of a laser which emits light in such a way that would, if we only opened one slit, allow us to detect illumination on the screen where we would expect if light was made of "packets" of light-energy called "photons".

Think of it this way. I have my laser-splitter device with two slits. I make my laser very "slow" so that only one photon should travel at the wall at one time. And I open one slit. I'm not going to see a single "dot" where the photons hit. Just like a classical particle, the photons might hit the edge of the slit and land a little bit off, or it might go straight through but off of dead center. However, on average, it's going to hit mostly roughly around some point right where I'd expect given the opening (that is, even given weird bounces, I'm going to detect at least some photons, and usually most, as if they were going straight throught the center of the hole). And that's what I find. Same if I open the other.

So, with either slit open, I get illumination around the point that describes a single particle going straight through dead center. I hit other areas as well, even really far out there because of some weird bounce, but I will always get illumination at the point which corresponds to the particle going through dead center.

Now I open both. What do I find? I never find the particle hitting either of the two points which correspond to a particle going through dead center. With either slit open, the illumination would tend to concentrate at the point which corresponds to the path a particle going through the very center of the opening would end at. But I also will always get illumination elsewhere. It's just that the most illumination will be at that "dead center point".

With both slits open, the probabilities of detecting single photons hitting either "dead center" points doesn't just change. It disappears. I make the laser so "slow" it only sends through a photon every century, and let it go for billions of years, but it will never hit the "dead center" spots. Instead, I will consistently find other "illumination" spots which don't correspond to anything a photon can do. No matter how a classical particle gets bounced around, this doesn't explain why I can never get it to go right through either slit such that I can detect illumination at the point corresponding to either paths a particle travelling through the slits would take. It just won't happen.

Why, if there are "really" photons going through the slits, do they never travel through either one?

 

[idav]

AFAIK, a given particle's wavefunction has a non-zero magnitude (i.e. non-zero probability of being found there) everywhere that has equal or less energy than the particle. This includes the other side of the universe - the probability of being found there is just very small.

Well I believe you but doesn't sound very practical.

How do you know there is an "actual photon" or subatomic particle? They don't actually load up a some "quantum cannon" with individual particles. For the double-slit experiment, we have instruments that allow us to take something like light in the form of a laser which emits light in such a way that would, if we only opened one slit, allow us to detect illumination on the screen where we would expect if light was made of "packets" of light-energy called "photons".

Think of it this way. I have my laser-splitter device with two slits, and I open one. I make my laser very "slow" so that only one photon should travel at the wall at one time. And I open one slit. I'm not going to see a single "dot" where the photons hit. Just like a classical particle, the photons might hit the edge of the slit and land a little bit off, or it might go straight through but off of dead center. However, on average, it's going to hit mostly roughly around some point right where I'd expect given the opening (that is, even given weird bounces, I'm going to detect some photons as if they were going straight throught the center of the hole). And that's what I find. Same if I open the other.

So, with either slit open, I get illumination around the point that describes a single particle going straight through dead center. I hit other areas as well, even really far out there because of some weird bounce, but I will always get illumination at the point which corresponds to the particle going through dead center.

Now I open both. What do I find? I never find the particle hitting either of the two points which correspond to a particle going through dead center. With either slit open, the illumination would tend to concentrate at the point to that which describes the particle going throught the very center of the opening. But I also will always get illumination elsewhere, including the point as if the other slit were open. It's just that the most illumination will be at that "dead center point".

With both slits open, the probabilities of detecting single photons hitting either "dead center" points doesn't just change. It disappears. I make the laser so "slow" it only sends through a photon every century, and let it go for billions of years, but it will never hit the "dead center" spots. Instead, I will consistently find other "illumination" spots which don't correspond to anything a photon can do. No matter how a classical particle gets bounced around, this doesn't explain why I can never get it to go right through either slit such that I can detect illumination at the point corresponding to either paths a particle travelling through the slits would take. It just won't happen.

Why, if there are "really" photons going through the slits, do they never travel through either one?

They don't only do the experiment with a laser beam. They also do the experiment, as you have noted as well, with one individual particle at a time that can be observed in a quantum state prior to shooting it through the slits.

It is particle that acts like a wave which is why it does nothing with one slit but gets interference with two. When you have only one slit you have a straight shot and no room for any interference. When shooting through two slits your getting interference from the second wave that was created due to having a second slit.

 

[LegionOnomaMoi]

They don't only do the experiment with a laser beam. They also do the experiment, as you have noted as well, with one individual particle at a time that can be observed in a quantum state prior to shooting it through the slits.

They never do this. It's not possible. What is really going on is related to the only reason we started re-interpreting classical waves. In classical mechanics, you can make a wave "hit" something with arbitrarily small effect. Moreover, the way you change how "hard" the wave hits something is not discrete (that is, it is not made up of individual "units" or "packets" of energy). So if I want to detect something very small, all I need is to make my wave (sound, light, whatever) very, very "soft": the frequency of "waves" and their size can be arbitrarily reduced so that when the wave hits what I'm trying to detect, the wave is so small that it doesn't affect what I'm trying to detect.

And Young showed that light behaved like these waves. However, this idea of "waves" being continuous (not composed of units) which I can make arbitrarily "big" or "small" and make the frequency of the waves arbitrarily high or low, didn't explain why actually trying to do this doesn't work. That is, if I have some device which can change the frequency and amplitude of a wave, whether light or anything else, I should be able to make it very, very, very focused but also make the frequency very, very, very low. So arbitrarily focused and low, that whatever the waves hits should not be affected. I can also do the reverse, and do either along a continuum.

But the problem that Einstein "solved" concerned light not doing this. I have a given "beam" of light, and I shoot it at a thin metal. I should be able to turn up the frequency and amplitude (wave size) to blast the metal to bits, and do the reverse. Moreover, I should be able to do so along a continuum, such that however much I increase or decrease how "big" and "fast" the waves are hitting the metal, the reaction of the wave hitting the metal is relative to this change.

It isn't. So for very "slow" waves, I should (according to the "physics" of classical waves) be able to increase their size so that even though the frequency is low, the affect is the same as a "smaller" but "faster" wave. I can't. Einstein showed that you can explain why light won't work like this, but only if you assume that light is made up of "discrete" units, or "packets", of "photons".

But nobody then got out a device and chopped light up into photons. It's mathematical. It explains the effect we get when we make light hit something in certain ways. And we never "fire" single photons that we actually ever know about apart from the fact that we know light is coming out of a device, and we know it is hitting something somewhere, and we have the math to explain this in terms of discrete units.

That's as close as we get to ever "firing" a photon. Having a beam of light which is mathematically described as being composed of discrete units. Instead of waves with increasing/decreasing amplitudes and frequences, like we thought, we are really increasing the amount of "photons" we send. And it works, so long as we have only one slit open (or don't look when we have more than one) and we shine a "focused" light at the slit. We can detect it on a screen focused at one point in particular: where we imagine a classical particle would most likely hit, which is the point corresponding to the path (or trajectory) of a particle going straight through the center of the slit. Again, it does hit elsewhere, but with either slit open, the one thing we know is that most of the the light is going to be detected at the point we'd expect it to if it were made up of units or light-particles or quanta or photons.

So we shine our light using a very delicate device, which tells us that (given all the math and experiments) we're sending one "packet" at a time, say every 5 minutes. We have two slits, but only open one. The "light" isn't going to hit dead center with either one open, and we will expect bounces here and there, but if either slit is open, after a while of firing one "unit" of light at a time, we are going to detect illumination mainly at the point we'd expect if the unit went through the opening near or at the center.

We don't move our device at all, or the splitter screen, or the detection screen, but now we open both slits. So nothing has changed except that both slits are open. If light is composed of "units", then however these hit the same "splitter" screen they've been hitting, all we've done is increase the ways in which they can go through instead of bounce of the edges of the opening or never go through. So we'd expect that perhaps we get weirder bounces (now the units can hit the edges of either slit, and bounce off in more ways), but we haven't changed the "amount" of light we're shining at the splitter, and we haven't changed the position of anything, so we'd expect that the only change is that we have two places where most units hit. Now that each unit we send has two ways it can go through, however many "bounce" off or hit the edge, after a while of sending one unit at a time, most units we will detect as if they travelled down and went through one of the openings without hitting the edges.

Only now these two spots are the only places we never find them. We don't just get weird bounces or different probabilities. We get weird probabilities, sure. But the one thing that never happens is the detection of a "unit" hitting the either of the spots on the screen which would let us know that the unit went through either slit without hitting an edge. That just doesn't happen. It did a minute ago, with either one of the slits open. Whatever edges the light hit, most units still went through the slits (at least that's what our detection shows).

Yet without moving the light-emitter at all, or changing the amount of light coming out, the same amount of light which used to show up going through either one of the slits now never goes through either one.

It is particle that acts like a wave which is why it does nothing with one slit but gets interference with two.

It absolutely does something with one slit. If we shoot light with one slit open, the units of light we think are there will be detected as units of light, sometimes hitting over here, sometimes hitting way over there, but mostly hitting the area of the detection screen which corresponds to the "lines" or "paths" going from the light emitter through the slit (without hitting an edge or bouncing off of the splitter screen entirely). If we open both slits, that word "interference" really means that we never find the "units" travelled down either path through the slits. They are never detected where we would expect a unit of anything to go if it went through either one of the openings.

When shooting through two slits your getting interference from the second wave that was created due to having a second slit.

How was the "wave" created? We have "units" of light going through openings. With two openings, we never find a single unit which went through either one. We'll detect "hits" of something in lots of places, but never there.

 

[idav]

They never do this. It's not possible. What is really going on is related to the only reason we started re-interpreting classical waves. In classical mechanics, you can make a wave "hit" something with arbitrarily small effect. Moreover, the way you change how "hard" the wave hits something is not discrete (that is, it is not made up of individual "units" or "packets" of energy). So if I want to detect something very small, all I need is to make my wave (sound, light, whatever) very, very "soft": the frequency of "waves" and their size can be arbitrarily reduced so that when the wave hits what I'm trying to detect, the wave is so small that it doesn't affect what I'm trying to detect.

And Young showed that light behaved like these waves. However, this idea of "waves" being continuous (not composed of units) which I can make arbitrarily "big" or "small" and make the frequency of the waves arbitrarily high or low, didn't explain why actually trying to do this doesn't work. That is, if I have some device which can change the frequency and amplitude of a wave, whether light or anything else, I should be able to make it very, very, very focused but also make the frequency very, very, very low. So arbitrarily focused and low, that whatever the waves hits should not be affected. I can also do the reverse, and do either along a continuum.

But the problem that Einstein "solved" concerned light not doing this. I have a given "beam" of light, and I shoot it at a thin metal. I should be able to turn up the frequency and amplitude (wave size) to blast the metal to bits, and do the reverse. Moreover, I should be able to do so along a continuum, such that however much I increase or decrease how "big" and "fast" the waves are hitting the metal, the reaction of the wave hitting the metal is relative to this change.

It isn't. So for very "slow" waves, I should (according to the "physics" of classical waves) be able to increase their size so that even though the frequency is low, the affect is the same as a "smaller" but "faster" wave. I can't. Einstein showed that you can explain why light won't work like this, but only if you assume that light is made up of "discrete" units, or "packets", of "photons".

But nobody then got out a device and chopped light up into photons. It's mathematical. It explains the effect we get when we make light hit something in certain ways. And we never "fire" single photons that we actually ever know about apart from the fact that we know light is coming out of a device, and we know it is hitting something somewhere, and we have the math to explain this in terms of discrete units.

That's as close as we get to ever "firing" a photon. Having a beam of light which is mathematically described as being composed of discrete units. Instead of waves with increasing/decreasing amplitudes and frequences, like we thought, we are really increasing the amount of "photons" we send. And it works, so long as we have only one slit open (or don't look when we have more than one) and we shine a "focused" light at the slit. We can detect it on a screen focused at one point in particular: where we imagine a classical particle would most likely hit, which is the point corresponding to the path (or trajectory) of a particle going straight through the center of the slit. Again, it does hit elsewhere, but with either slit open, the one thing we know is that most of the the light is going to be detected at the point we'd expect it to if it were made up of units or light-particles or quanta or photons.

So we shine our light using a very delicate device, which tells us that (given all the math and experiments) we're sending one "packet" at a time, say every 5 minutes. We have two slits, but only open one. The "light" isn't going to hit dead center with either one open, and we will expect bounces here and there, but if either slit is open, after a while of firing one "unit" of light at a time, we are going to detect illumination mainly at the point we'd expect if the unit went through the opening near or at the center.

We don't move our device at all, or the splitter screen, or the detection screen, but now we open both slits. So nothing has changed except that both slits are open. If light is composed of "units", then however these hit the same "splitter" screen they've been hitting, all we've done is increase the ways in which they can go through instead of bounce of the edges of the opening or never go through. So we'd expect that perhaps we get weirder bounces (now the units can hit the edges of either slit, and bounce off in more ways), but we haven't changed the "amount" of light we're shining at the splitter, and we haven't changed the position of anything, so we'd expect that the only change is that we have two places where most units hit. Now that each unit we send has two ways it can go through, however many "bounce" off or hit the edge, after a while of sending one unit at a time, most units we will detect as if they travelled down and went through one of the openings without hitting the edges.

Only now these two spots are the only places we never find them. We don't just get weird bounces or different probabilities. We get weird probabilities, sure. But the one thing that never happens is the detection of a "unit" hitting the either of the spots on the screen which would let us know that the unit went through either slit without hitting an edge. That just doesn't happen. It did a minute ago, with either one of the slits open. Whatever edges the light hit, most units still went through the slits (at least that's what our detection shows).

Yet without moving the light-emitter at all, or changing the amount of light coming out, the same amount of light which used to show up going through either one of the slits now never goes through either one.


It absolutely does something with one slit. If we shoot light with one slit open, the units of light we think are there will be detected as units of light, sometimes hitting over here, sometimes hitting way over there, but mostly hitting the area of the detection screen which corresponds to the "lines" or "paths" going from the light emitter through the slit (without hitting an edge or bouncing off of the splitter screen entirely). If we open both slits, that word "interference" really means that we never find the "units" travelled down either path through the slits. They are never detected where we would expect a unit of anything to go if it went through either one of the openings.

There are actual particles and not only photons are used. I have read that in the experiments instruments can be used to literally grab or pick up a particle and send it through the slit and box experiment and determine which box the particle landed in.

The rest I pretty much agree with. I don't have any issue on the results that your describing I'm merely giving a different interpretation of what the results of the experiment are. The places that don't get hit is a direct result of the wave aspect of the particle interfering with the direction the particle is going. The places that don't get hit were blocked off somehow which is where I describe it as a "classical" type of interference.

How was the "wave" created?

IDK. If I knew how a particle acts like a wave I'd have solved the quantum mystery. Regardless of how the experiments show that is precisely what is happening. The wave aspect is going through in a way that a "classical" particle never would.

We have "units" of light going through openings. With two openings, we never find a single unit which went through either one. We'll detect "hits" of something in lots of places, but never there.

Yes I know, thus the mystery of the dual particle wave nature. But we never find that the particle is in multiple places like in the box experiment. Even if it appeared to give evidence of being in multiple boxes, when you search for the particle it is always only in one box.

 

[LegionOnomaMoi]

There are actual particles and not only photons are used. I have read that in the experiments instruments can be used to literally grab or pick up a particle and send it through the slit and box experiment and determine which box the particle landed in.

What you have read is either drastically oversimplifying, or is describing a thought experiment (not something actually done), or is just plain wrong. The typical undestanding within modern physics is that particles don't exist. There are only "wave-like" entities which are variously described as "smeared out" or a "duality" or some such thing. It is an unfortunate aspect of modern physics students, for example, spend several semesters of calculus learning about integration techniques (the calculus, at it is often called, is broken down into to main and very related notions: differentiation and integration), often specifically to understand physics where integration is so vital, until they are told that what the learned is not only outdated, generally useless, and unecessarily complicated method integration, which makes learning modern integrals harder than it need be.

The same can be said about the general way in which physics is taught, from high school through undergrad years. Classical mechanics is introduced, reinforced, and terms like "measurement" and "system" and "particle" drilled into the heads of students, until they reach a certain level at which they are not only told that much of what they were taught is wrong, but that they have to understand the same terms ("measurement", "state", "vector", "particle", etc) to mean often completely different things. Most have learned about vectors through classes in physics more than they have in some multivariate mathematics class or abstract algebra class, and thus to them "vector" is not only understood in terms of Euclidean space, but specifically as "arrows" or "pointers" in the three-dimensional world we experience which describe things like velocity (unlike speed, velocity has a direction, and therefore the vector tells you not only how fast an object is moving, but in which direction). Now they are introduced to "bras" and "kets" and vectors over the complex numbers, which behave quite differently to the vectors they are used to dealing with and which they understood (unlike math majors) as rather fundamentally related to specific things in physics, or at least a specific way of describing things in physics.


The same is true of "particles". There are none. If you get caught up thinging in terms of "particles" you will never properly misunderstand quantum mechanics, like an actual physicist does.


Of fundamental importance, related to the problem of thinking about particles and waves, is that this can give the impression that if only we had better measurement devices we could know exactly what these quantum entities we call things like "electrons" or "photons" are, and in particular how they behave in a quantum system.

There is no way to do this. It is not a matter of praticality, of better measurements, of newer technologies, etc. However much newer experimental techniques and devices allow us to understand quantum systems, an integral, fundamental uncertainty will remain, because this is what quantum systems are. Uncertainties. The only possible way to detect something at that level is with some other thing at that level, which means it is not possible to measure, observe, or in any other way "detect" quantum processes in a way which does not fundamentally alter them.

Any experiment or description you have heard or read which says otherwise would be collapsing all modern physics. It would erase completely our fundamental understanding of the subatomic world.

IDK. If I knew how a particle acts like a wave I'd have solved the quantum mystery.

They don't "act". The mystery isn't how particles act like waves, or vice versa, but how the quantum world, which is fundamentally different from that which we experience, somehow relates to the world we experience in that it not only makes it up, but does so in such a way that we experience something different in some quite unknown way (apart from knowing, for example, that it is fundamentally different).

Banish "particles" from your mind.

 

[idav]

They can observe it, it is delicate though. They are particles as in electrons photons and atoms. They do "spooky" things which is the problem. The "wave" aspect of it is coming from its charge states with superpositions or entanglement due to interacting with each other.
Quantum measurements leave Schrödinger's cat alive - physics-math - 03 October 2012 - New Scientist