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Naw. “observing” doesn’t mean, a human looks at the data. It means, we force the particle to be in one place on a quantum level. the word “observation” is overloaded in some sense
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It only kinda works like this. If you have two slits, looking at it or not, you will see the top one. Now, the really weird thing is that if you fire a single photon at a time, you will still get the top one over time, suggesting that the single photon is somehow going through both slits and interfering with itself to do so. But the even weirder thing is, if you place a detector in one of the two slits to check which slit the photon is going through? You suddenly get the bottom picture.
My understanding is. Every method of measurement influences the results.
I’m in cognitive sciences not physics. But it applies there as well.
The measurement method always interferes in some way with the result.
I have used this example with helping students understand research methods.
Doesn’t matter how “non-interfering” you think your method is.
In some way or another, the act of measuring or the device used to measure (or both) changes the thing being measured.
Exactly, I like to imagine it with our senses.
In order to see something lightwaves had to have interacted with the objects we see.
In order to hear something objects had to have moved or interacted in a way to produce changes of air pressure.
In order to smell something an object had to have “lost” some of its molecules into the air.
Well, and touching and tasting are kinda obvious, your body has to directly interact with an object.
What constitutes “measuring” here? Is it in the wider sense of any quantification of an observation, or are there conditions?
Not a true expert, but I think it comes down to “observing” a particle/phenomenon like this inherently comes down to some sort of interaction, and it can’t just be neglected like you could on a macro scale. Even for something like holding a ruler up to an object and seeing what mark lines up, you’re relying on a bunch of light bouncing off the object (and the ruler) to be able to judge that. If the thing you’re trying to measure is on the order of one particle of light, blasting it with a bunch of anything is gonna affect it pretty severely, and who knows what a “ruler” would even mean in that analogy. So it’s less like some idea of sapient knowledge, and more like when you struggle to measure something like a tiny feather or single bead of Styrofoam, like you can’t even get near the thing without the wind from moving or some random static or something else moving the thing around uncontrollably, except many orders of magnitude more sensitive.
Question for the ages
Since the start of the war against Iran, I started taking the bus instead of driving to work. Now and then, someone will step off the bus in a way that makes me observe a certain post-impact soft tissue oscillation. It’s definitely an observation, but it could maybe count as measuring, in which case it would change the outcome?
shy proton theory
uwu 👉👈
intference pattern by light wavelengths, used by many animals to give them those iridescent colors.
It doesn’t work like this, popular misconception. It is cool in sci-fi though.
The easiest way to understand this is in terms of mutual information.
If we both flip a coin independently of one another, then both coins have a 50%/50% chance of being heads/tails and the distributions are independent of one another and thus uncorrelated, but imagine the two coins are initially attached to one another, flipped, and then we separate them. Now they’re both still 50%/50% for heads/tails but are perfectly correlated, so they are guaranteed to have the same value, and so if you know one, you know the other. In this case, the coins are said to have mutual information on one another.
It turns out in the physical world that mutual information, or more specifically quantum mutual information (QMI), plays a very important role. The marginal statistics on the behavior of a system can depend upon whether or not it shares mutual information with something else. You see this in the double-slit experiment because if you record the which-way information of a particle, then necessarily it must have interacted with something to record its state, and thus whatever measured it must possess QMI between itself and the particle, and thus the particle’s marginal statistical behavior will change.
This is in no way unique to human observers or human measurement devices. You can introduce just a single other particle into the experiment that interacts with the particle such that they become statistically correlated and it will have the same effect.
QMI is rather counterintuitive because you can establish QMI in ways that you would intuitively think would not impact the system being measured. For example, you can have an entirely passive interaction whereby only the measuring device’s state is altered and not the particle in order to establish QMI between them.
You can also establish QMI without an interaction at all, such as, imagine that the measuring device is only placed on 1 of the 2 slits and you only fire a single photon and that photon is not detected. If it’s not detected, you still know where it is, because it must have traversed the slit the measuring device was not on. Hence, the non-detection of something can still be a detection and thus can still establish QMI.
Intuitively, you would think a passive measurement, or a measurement that does not even involve an interaction at all, should not alter the system’s behavior. But the mathematical structure of quantum mechanics is such that the system’s marginal stochastic behavior is genuinely statistically dependent upon the quantity of QMI, and so things you would intuitively believe should not affect the system do, in fact, affect the system.
You can even use this effect to detect the presence or absence of something without ever (locally) interacting with it.
In the Mach-Zehnder interferometer, the photon can take two possible intermediate paths, we’ll call them A1 and A2, but both end up at the same place. Then, at the end of the experiment, it can take two possible paths again, B1 and B2, with a detector placed on both paths. You find, in practice, that there is a 100% chance the photon will show up on B1 and 0% on B2, unless you block either A1 or A2 with your hand, then it will have a 25% chance of showing up on B1, 25% chance of showing up on B2, and 50% chance of not showing up at all (because it was blocked by your hand).
The reason this is interesting is because, without your hand blocking an intermediate path, there is a 0% chance it will show up on B2, but with your hand blocking one, it changes to 25%. Thus, if you measure a photon on path B2, you know with certainty that someone’s hand must be blocking A1 or A2, yet, clearly the photon did not traverse the path of the hand or else it would have been absorbed by the hand and you would have detected nothing. You thus can deduce the presence/absence of the hand from a particle’s behavior that never (locally) interacted with it, and so logically speaking, the hand must be having a non-local influence on the statistical behavior of the particle.
This influence is due to the fact that if the particle interacts with the hand, it will be absorbed into it and slightly will alter the states of the particles in the hand, and if it does not interact with the hand, it will not do this. Thus, you could in principle look very closely at the particles that make up the hand and deduce whether or not the particle took the path the hand is on based on whether or not this alteration occurs, and thus there is QMI between the hand and the particle’s path, regardless of whether or not the particle actually interacts with the hand. The mere presence or absence of this QMI changes the particle’s behavior.
Nah, man, it’s literally how it works (for all we know). The wave function doesn’t collapse until the data is read. You can’t prove otherwise, so people are free to believe it.
This was a joke. This is a joke community. I was being facetious when I said “literally”.
However, there’s truth in what I said. How do you know that the entire experimental setup is not in a superposition right up until you observe the result. I mean, you obviously have to look at the result of the experiment before you know what happened in the experiment, and until you do, the entire experiment could be in a superposition of [interference pattern] and [no interference pattern].
However, this is not really what the meme is saying, so I guess my joke was dumb, and I deserve the downvotes.
Your joke was funny you just forgot the /s
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Haha, no I haven’t. I don’t believe in magic. I watch mainstream YouTube science channels, and not any “mystical” ones. PBS Spacetime, Dr Ben Miles, Quanta Magazine, Sabine Hossenfelder, etc.
So, I ask you: please design an experiment that proves the outcome is determined precisely when the detector detects the particle going through the slit, and not when a person observes the screen or a recording the detector made. You can’t. You can’t prove that the detector detected something until you look at the result, and until you do, for all you know, it’s in a superposition. That’s all I’m saying. You know, shorting your scat. Everyone knows the shorting your scat experiement.
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A reply to your edit: You need to work on your grammar, spelling, and punctuation. I can’t understand a thing you’re saying.
I’m KFC Double Downing on the double slits being doubly doubtful until you’ve observed the result.
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I mentioned my sources of science news specifically because you accused me of being misled by… somebody. So fuck off with your mockery of me for trying to disuade you of that notion.
This started as a joke, and you’re just being an ass.
You have a stick up your butt. I observed it.
Does the result of the experiment change if there’s a sensor active that records data to a hard drive that no one ever looks at and it just gets deleted? Does the result change again if someone decides that if they get a wave pattern, they will interrupt the deletion process and look at the data?
Does the result of the experiment change if there’s a sensor active that records data to a hard drive that no one ever looks at and it just gets deleted
Yes. It collapses the wave function. There is no need for something ‘conscious’ to count as an ‘observer’.
Your second question is moot, because the first part counted as an observation.
I don’t understand. How can they “get” a wave pattern if they didn’t look at the data?
The wave pattern is on the photo plate, the data that never gets looked at is from a sensor on one or both slits that measures whether the projectile passed through that slit.
But the way it works is only the top one if im not mistaken
Well, no. Not if you put a detector in one of the slits. It collapses the wave function, and the interference pattern disappears. The meme is a joke that your eyeballs are the detector, which is not true.
I was making a bit of a joke myself to get people to think about when the collapse actually happens. It could occur as late as when you look at the screen, and you can’t prove otherwise. You know… like, “is the moon still there when you’re not looking at it?” Except for real.
Agree to disagree!
Nothing to agree or disagree with, you’re factually incorrect. The observer effect has nothing to do with whether someone’s eyes are looking toward it or not. It basically just means when a process is happening and anything external occurs to it then that will change the way the process is happening.
I was curious, so I went to Wikipedia, as one does.
A notable example of the observer effect occurs in quantum mechanics, as demonstrated by the double-slit experiment. Physicists have found that observation of quantum phenomena by a detector or an instrument can change the measured results of this experiment. Despite the “observer effect” in the double-slit experiment being caused by the presence of an electronic detector, the experiment’s results have been interpreted by some to suggest that a conscious mind can directly affect reality.[3] However, the need for the “observer” to be conscious is not supported by scientific research, and has been pointed out as a misconception rooted in a poor understanding of the quantum wave function ψ and the quantum measurement process
Edit: erhm. this isnt an ad for Wikipedia. the words just shook out that way. lol
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If anybody still doesn’t understand, when the wave function collapses, that is called observation. Again, from Wikipedia:
In various interpretations of quantum mechanics, wave function collapse, also called reduction of the state vector, occurs when a wave function—initially in a superposition of several eigenstates—reduces to a single eigenstate due to interaction with the external world. This interaction is called an observation and is the essence of a measurement in quantum mechanics, which connects the wave function with classical observables such as position and momentum.
Physics has this problem with naming things. They use words like “particle”, “observation”, and “spin”, among others, which are words that every English speaker knows, but then they use those words to describe stuff that’s actually only similar to the words everybody knows. This makes physics a lot more approachable for people who know nothing, but then completely confuses people with only a little knowledge.
This makes physics a lot more approachable for people who know nothing, but then completely confuses people with only a little knowledge.
My favorite example of this is the use of “stress” and “strain”. In common language they’re synonyms, but in Physics they’re definitely not.
“Theory” is another bad one in all of science. That’s what leads knuckleheads from saying dumb shit like “evolution is just a theory!”
In general, I agree, but spin is quite surprising in how much like angular momentum and dynamos it behaves. Either way, we don’t know enough about it yet, and it’s at best a coincidence.
Shout-out to floatheadphysics (Mahesh) for his video on spin. The way he steps through the learning process like it’s a conversation with the giants that gave us the knowledge (based on their writings) and how he presents it with all the excitement of “getting it” is cathartic.
There isn’t a scientific definition for “observation.” In the Copenhagen interpretation, it really is treated just as vaguely as the colloquial definition, something the physicist John Bell complained about in his article “Against ‘Measurement’”, that the textbook axioms of quantum mechanics are inherently vague because they refer to “observation” or “measurement” which is not itself defined in the axioms. Saying that observation is just “when the wavefunction collapses” is a circular definition and doesn’t answer anything, because then we can just ask, “when does the wavefunction collapse?” and the only answer the textbook axioms give is “when you observe/measure it.”
I think we all understand the joke is that the eyes represent the endpoint of the observation apparatus. That is the first panel is isolated and the second panel has a detector measuring the path that the scientist then looks at.
So yeah, “eyes” don’t cause a waveform collapse. But how does a two panel cartoon with no words represent no interaction? First panel is blank?
On the other hand, maybe our personal observation doesn’t just cause a waveform to collapse, but also collapses a logical path for said wave backwards into time. This would mean that even the results of the initial observation only collapse at the moment you look at them.
So at what point in human evolution was one human conscious enough to have the first observation and therefore spring quantum mechanics into existence in the universe?
Obviously any living creature can become entangled with the quantum experiment if you build the right apparatus. Build a machine that kills a cat if an atom decays, and you’ve made cats into quantum observers. When the cat observes the experiment by not dying, it collapses from the cat’s point of view. When you observe the cat, it collapses from your point of view.
What if both human evolution and “other humans” follow the same unfolding? You’d create all of that in every moment. Even the memories and logistics needed for that. That would mean that there is only now and reality has been creating itself over and over again infinitely.
Someone gets it
That’s not “litterally” how it works then, just “figuratively”.
Observation in quantum mechanics isn’t like everyday observation. There is no passive observation, you have to interact with a particle to observe it. It’s like putting your hand in front of the hose to see if it’s on. You can see from the spray pattern that when the hose is “observed” the pattern changes.
and in this case, seeing the spray pattern is interfering the system not because it is “aware” of you seeing it, but in order to see it there must be light reflecting off it which certainly would have an effect for bombarding it and bouncing off it.
You are wrong though.
WE ARE WAVE, RESISTANCE IS FUTILE (unless you measure us), your biological distinctiveness will receive energy and transmit it in a periodic fashion
Ha! That’s what you think!
I’ll have you know, I sawed the legs off that periodic table.
It’s chaos I tell ya, all chaos!
Glob is awesome. IA! Fthagn!
only if you have robot eyes
I mean, technically
They should just show this in physics classes and skip all the boring words.
I mean, thats also how we got weird pseudoscience about how the universe shifts around our consciousness.
Its usually not made clear in school that things can only be measured by touching it or bouncing something off of it. On the macro scale, looking at something doesn’t move the thing you’re measuring because you’re just capturing the abundant photons that are already bouncing off the thing in the billions per second. On the quantum scale, looking at something involves shooting particles at the thing, which is often comparable to measuring how big a cat is by trying to bounce a kickball off it and measuring the angle it rebounds. It works, but you can’t expect the cat to continue behaving the same after being assaulted out of nowhere.
I bet if you wait a few more years they’ll be putting memes in science textbooks.
You used literally incorrectly, “that really makes me want to literally smack a crowbar upside your stupid head.”
It’s a matter for interpretation, but I think they used “literally” correctly, but they were just wrong on the science.
Like, if I say that when the sun appears over the horizon, it is literally plaid colored, I am using “literally” correctly, but the fact that I am conveying is wrong.
Words mean what people think they mean when they say them. Nothing else. Miscommunication can occur if the speaker and listener don’t have the same concept in their head, but it doesn’t change the fact that words are just people serializing their thoughts into sounds or text. Dictionaries are not prescriptive, they are documentative.
EDIT: In other words, “literally” is in literally the dictionary with a definition including how OP used it.
https://www.merriam-webster.com/dictionary/literally
If you can’t accept that, can you accept that they were being facetious? This is a joke community, after all.
To the downvoters: go read some semantic theory. https://en.wikipedia.org/wiki/Semantics
All the more reason to really reflect on how we use words. When there’s confusion and misunderstanding, should we just accept it because that’s how it is, or should we consciously decide if we are helping or hurting communication through the words we choose to use?
I “literally” don’t care if you use “literally” to make an obviously facetious joke like OP did.
Stop philosophizing over a joke. We are in “science memes”.
I will philosophize, phallosophile, and fallacify as much as I want thank you. Memes are important. (I’m of course using the strict Dawkins definition here.)
Not exactly. If I were to tell you that I believe in creationism and that the world is 6000 years old, but that it means what you think evolution and cosmology mean and that I’m just using different words, you probably still wouldn’t want me teaching your kids in school about science.
Or, at least, I would hope not.
We were talking about colloquial use of a word like “literally”, and not entire bodies of science being replaced with religious terms. Those two things are not even remotely similar.
Okay but that’s a dishonest argument. Sure reality is just perception and perception is unique to the individual. All that said words have meaning which we have agreed upon. Otherwise I could write gibberish, call it meaningful text, and prove anything. It’s the fact that words have specific meanings which makes them useful. Otherwise it’s baby talk and that’s cute but not great for communication.
Yes, communication works best when people agree on what words mean, and a great, great many people have agreed that “literally” means things other than “literally”. It’s not gibberish to use it as such.
It’s not a dishonest argument at all. Language is not prescriptive. It’s constantly evolving. New words are invented all the time, and old words take on new meanings all the time.
Do you ever use “awesome” to mean “super cool”? Congratulations, you’re misusing the word! How about “egregious” as in a bad error? Wrong! How about “fantastic” as meaning “wonderful” or “great”? Also wrong.
Even when words do have specific meaning, if you don’t know the meaning they are useless to you, so it might as well be gibberish. Can you speak Swahili? Does that mean it’s gibberish? Of course not.
You’ve obviously given this some thought. I’m curious what you think of an example. Think about this sentence: “The theory of gravity can help explain things.” And then this one: “Evolution is just a theory.” Is there a difference in what the word “theory” means?
The context of what each speaker is saying matters. Words don’t have much meaning in isolation except for simple ones like “no”. You could have a degree in the Philosophy of Science and still struggle to define “theory” accurately and succinctly.
One speaker is using the word as a positive thing (accurately). After all, a theory is the best we can say about how the world works. The second speaker is using the word pejoratively. In that sense it actually doesn’t mean the same thing, and any scientist would argue that the second person doesn’t understand what they mean when scientists say “theory”.
Note: I said when scientists say theory. Words don’t have inherent meaning, so the speaker matters. The speaker can only hope their audience takes their words the way they’re intended. There’s no guarantee that they will.
The second speaker is trying to refute science by quoting scientists, yet using the word in a way that scientists don’t. That’s obviously dumb. But it is the way that most non-scientists use the word, so you could say the second speaker is just confused about what scientists have been saying when they use the word. The scientists’ goal should be to correct the second speaker’s understanding of what scientists mean when they use the word. The word itself is not actually important. You can get across the meaning without ever using the word itself.
So who’s right and who’s wrong? Neither. It’s a simple misunderstanding of how scientists uses the word when they speak. Unless, of course, the second speaker knows the scientific definition, and is pretending to not know in order to pander to an audience.
I agree with that. In my ideal world, the person who said “evolution is just a theory” would hear the scientist explain the difference and think “Ah, using the word ‘theory’ like I have before is maybe not wrong in some contexts, but it’s causing confusion and in that sense it weakens our language. I will therefore be careful and use another word instead, perhaps ‘speculation’, to sharpen our shared language into a more precise tool for understanding each other. Since words mean what we all agree they mean, they are infinitely malleable and beautifully fragile, but we all have the opportunity, and duty, to influence the direction as we head into the future.”
