A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
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This is a science community. We use the Dawkins definition of meme.
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.
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.
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 doesnt change the fact that words are just people serializing their thoughts into sounds or text. Dictionaries are not prescriptive, they are documentative.
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.
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".