Double Slit Experiment explained! by Jim Al-Khalili

[@eltonmaiyo]

As a game developer, I can tell you its for performance reasons. Why waste processing power rendering particle behavior when there is no observer to output to.

[@eltonmaiyo]

Hahaha maybe so, I suspect upgrades maybe soon forthcoming. The question is whether these design artifacts & other physical constraints are necessary or intentionally?

[@fkngeniuspappie]

Elton Maiyo With the possibility of our physical observations being selectivly simulated depending on if we're physically observing them, it also seems possible that on "the other side" there may be beings living out several lives, each time starting with a new redeveloping consciousness that can't seem to grasp the double slit theory. I wonder if they're then able to remember each and every life when on the other side ("unplugged" from simulated reality). The social implications of your lives lived's quality can then be a factor when it comes to your footing in the community hierarchy on "that side". Not that I believe in this, but it is interesting that the Hindu idea of reincarnation and karma that basically says your life lived determines how you'll return can fit in that far out logic. This can obviously also explain other realms of _being consciousness_, like heaven and scary enough, hell. Hell, if these beings are only nearly as messed up as humans they'll send the oppressed or misbehaving to shitty simulations for possibly an infinite time period. The knowledge a civilization with this capability can produce when the data of many simulations are mined could make them infinitely knowledgeable. Another possibility could be that you are just a learning AI component. So many possibilities opened up by this gap (slit) in our knowledge. kooky

[@eltonmaiyo]

Adriaan Serfontein Interesting ..observations :) The nature of base reality/"the other side" is an infinitely interesting subject to explore with equally infinite conceivable possibilities. Your theories makes sense.

[@kalahariskydive]

Well, as a developer your algorithm knows what area should be observable on the screen at any given moment and does the rendering accordingly. How can a 'dumb' particle 'know' when it has been observed?

[@SunnyApples]

As a CG artist, what particle system is being used here?

[@jimmydanger2223]

Getting this kind of thing free and recommended for you is definitely a positive of modern life

[@slangkam]

This comment can't be praised enough

[@jimmydanger2223]

@LisaBlooper what a load of verbal diarrhea

[@jimmydanger2223]

@myspeechles lots of things are free mate

[@nengthao5618]

And most folks can't even appreciate that. They spent it on useless things like tik tok

[@colmhauser9532]

The RI host a televised lecture every Christmas, usually explaining scientific concepts for the layman in relatively simple terms. If you enjoyed this I couldn't recommend them enough, this channel has many of them in their playlists.

[@jucklowe]

Seen this experiment described a dozen times,,,, this is about the best one. Bravo for helping my slow brain.

[@axion4523]

I hear ya!

[@kyannos]

I'm with you as this is the first time I really "get it" !! wish this guy was my HS teacher back in the day !!!

[@leecowell8165]

this professor is amazing. What he is stating is that the atom somehow KNOWS that its being "measured" or sensed. and thus it ALWAYS becomes a "particle". it will NOT interact! but IF you turn the "detector" OFF.. it doesn't know! and thus it just becomes a part of a "wave". yeah how does that atom KNOW about the EXISTENCE or ABSENCE of that detector?? thus if there's only ONE slit present the atom has no choice but to pass through that one slit. thus every atom that does so hits the screen in basically the same place. its ONLY when you open the 2nd slit that things get a bi "hairy". But as long as nobody is measuring the atoms perform as interference waves. BUT if you turn on a detector for just ONE slit NOW ONLY TWO DISTINCT patterns on the screen are formed (one directly behind each of the slits). The atoms are communicating. hey if I go through slot # 1 YOU go through slot #2!

[@dieseldanrr]

@@leecowell8165 p

[@eduardoaraujo8174]

@@leecowell8165 The atoms knows its being measured or you know the atom is being measured or not? Im new to this but this observation behaviour seems to be related to knowing or not knowing. I wonder if there was a way to put a detector that beeps in a frequency we cant hear and that no one knows that it beeps for example. What would happen?

[@penttiranta9730]

Even if we forget about thousands of other variations of this experiment with all the timetravel, causality breaking consequences, already the fact that a single atom behaves differently going through a single slit and double slit is enough to blow my mind.

[@amihart9269]

There are no causality breaking consequences or time travel.

[@goldnarms435]

@@amihart9269 There have been tests that have resulted in "reverse causality" concerning the double split experiment. This requires entangling two particles, and one travels a further distance than the other. The one that travels the shortest distance is not measured. However, if you measure the particle that travels further, it will be reflected in the interference pattern (or not) of the one that traveled the shortest. It's as if it knew the other particle was going to be measured, and thus its behavior is altered prior to the actual observation taking place.

[@amihart9269]

@@goldnarms435 Nope.

[@irasac1]

​@@amihart9269 care to elaborate?

[@nabuk3]

No, that's not the major inconsistency. The rub is that the pattern seems to depend on whether the atoms or photos are being "observed". But I think there is an explanation, which is that the device doing the detecting is interacting with the atom. Why didn't he explain how the detector works, to rule this out, if he believes it is not the explanation?

[@javiermachin1]

I’d say one of the Best double-slit-experiment explanations on the internet. Fills you with awe and curiosity about this wonderful universe we get to experience.

[@Oscaragious]

Can you explain how the detector detects? How can it detect the atom without touching it or shooting photons at it, potentially affecting its trajectory?

[@skwervin1]

@@Oscaragious You can with X ray plates in the old days, now we have better detectors that pick up the tiny charge the atom/particle deposits on the screen.

[@Red-Brick-Dream]

Given that it's a deliberately obfuscatory _non_-explanation, I have to disagree.

[@marcocurrin8122]

The same way we turn on three dimensional box inside out is the same thing that’s happening here we are the 1- looking down at the H2 on the periodic table. THE HUMAN SOUL IS THE FIRST ELEMENT

[@adamnguyen4517]

@@Oscaragious We can’t. At the quantum level to observe is to interact. This video was extremely oversimplified and feeds the popsci crowd (which isn’t bad since it gets people more interested in science). The popsci idea people seem to have is that observing (which means interacting) a photon causing change being the weird part, when its not. The weird part is the multiple questions and experiments that followed and are still continuing to this day.

[@IIT24Aspirant]

The people are laughing but just the mere thought of it runs chills down my spine

[@garrybarry4286]

exactly

[@joxyjoxyjoxy1]

Why?

[@garrybarry4286]

@@joxyjoxyjoxy1 well maybe we live in a predetermined universe, that's the scariest outcome. or maybe we live within a simulation or a conciseness, but the chances that we live within the universe that is material by nature is probably untrue

[@joxyjoxyjoxy1]

@@garrybarry4286 or maybe God just likes messing with us.

[@garrybarry4286]

@@joxyjoxyjoxy1 A bible god? Zero chance

[@johnvarley4561]

I hope this analogy helps others to understand. When people say "observing" changed the result, they do not mean the physical act of watching the experiment - they mean the act of measurement changed the PROPERTY of the thing they were watching. My analogy; when you take your temperature, the thermometer you use SUCKS heat away from you (consider a metal teaspoon in a cup of tea, the spoon gets hot because heat energy is being transferred from the liquid to the spoon. The tea is actually getting cooler by transferring heat to the spoon) Therefore, the act of using an instrument to measure the temperature of something CHANGES the temperature of that very same thing. I believe this is the same thing (but of course, probably more complex) but am happy to be corrected. It's a layman's explanation which I feel stands up

[@santos122122]

But if they are watching only the upper slit, why the atoms that go trough the bottom slit don't still behave like waves since no one interferes with them?

[@meganz020]

This is actually incredibly helpful, dude. Thank you!!!

[@davidfiler5414]

@Dirk Knight Almost 100% of people? What's that 99 and half % peeps? or 99 and three quarters% peeps? Be specific man, or don't you know your sums?

[@davidfiler5414]

@Dirk Knight Were you missing me 100% or only 99.99%.

[@davidfiler5414]

@Dirk Knight Oh well, that would make it 100%. Well done, there's a good boy.

[@skinfax]

Even though I struggled over this for the last 35 years I never stop to be amazed by this. And this explanation is simply clever AND cheerful. Cheers for that!

[@nabuk3]

What explanation? No explanation for the inconsistent results were given at all. In fact we're told we'll get a Nobel prize if we come up with one. Did you even watch the whole video??

[@ecairol_m]

​@@nabuk3he meant explanation of the problem, not the solution. It was explained in simple terms so that we can understand it. I bet that "a device that beeps" is just a metaphor for something more complex.

[@normjohnson4629]

I tried the double slit experiment at home. The wife was not impressed.

[@PR0Z0MBIE9877]

lolol

[@HylianHero69]

great fuckin comment, keep experimenting

[@PR0Z0MBIE9877]

Alex G haha i think he meant it in a sexual way

[@HylianHero69]

Hahahahah me too goof ball

[@lifer3860]

That was a funny ass comment! I am still cracking up!😅

[@MrWookLoaf]

"According to quantum physics, you cannot "just" observe something. That is, quantum physics recognizes that to make a observation, you must interact with the object you are observing " - Stephen Hawking.

[@WAKMM]

Im not sure if this was stated before the delayed choice experiment was done in 2007

[@crystald3346]

That’s not true just because Stephen Hawking says so. There are thousands of experiments on this, delayed choice is a perfect example.

[@redcell9248]

That has more to do with the Heisenberg Uncertainty Principle than it has to do with this experiment.

[@alahjandrodagrate1611]

Observing is interacting

[@ONEMindCoaching]

Could you tell me the source of this quote pls?

[@cvikastube]

0:57 - with light 2:08 - with sand 5:48 - without camera 7:34 - with camera

[@denisa7090]

Thanks!

[@Parshvamehta1991]

Thanks but KZbin ads ruined it!

[@ernestamoore4385]

It's the photons of the camera recording them that affects their behaviour. It's not a mysterious effect.

[@David-jy7vh]

@@ernestamoore4385 lol sure Mr einstein, you should be a scientist. 🤧

[@obtheserverdmt]

@@ernestamoore4385 I thought cameras contained sensors capturing photons rather than projecting them. However, you may be on to something, because it might be true that when the photon hits the material making up the camera sensor it is absorbed and an electron is released. Could these electrons being released from the camera sensor as the detector observes the atoms moving through the slit have an impact on where the atoms travel to as they pass through the slits?

[@AlbinoMutant]

I'm not a physicist, so most of the time I'm just going about my life. But periodically, every few years, I remember this experiment, and I remember there is something about it that I find eerie. I can never remember exactly what it is, so periodically I review the experiment as I just did with this video. And once again, I'm left with the disturbing feeling that something is very wrong with our reality. It's almost like we are not supposed to be aware of certain things, we aren't supposed to be observing them, and when we do, they are altered to keep us from seeing what's really there. If I was running a simulation and didn't want my simulated agents to discover they are in a simulation and start trying to hack their way out, I would implement something to prevent discovery of the fundamental nature of their reality. Every time they tried to look at the substrate of their existence, I would show them something other than the processor they were running on. I don't know about anyone else, but this experiment has caused me to increase my estimate of the probability that we are living in a simulation.

[@adamnguyen4517]

This experiment isn’t the confusing part. Everything in this video can generally be explained. At least the “relevant” parts. The questions and experiments that followed are what really get whacky. So to relate it to you: if you think we’re living in a simulation, Quantum physics is so whacky the simulation is debating on whether its living in a simulation!

[@IAyala1010]

@@adamnguyen4517 this is comforting 😂

[@adamnguyen4517]

@halligalli I'm just saying while quantum physics has some unanswered questions, its also a relatively new science. Just give us a century or two and I bet we'll have it down to a science, literally. Then we'll move on to the next weird phenomena of reality.

[@steviesteve750]

@@adamnguyen4517 You didn't mention the real elephant in the room: quantum gravity. The idea that time doesn't exist in the human sense of a sequenced order of life, everything exists simultaneously, and life is the process of sequencing those events into some perceived order. And if that is so, then just why?

[@adamnguyen4517]

@@steviesteve750 Well thats just one train of thought, but if that does turn out to be the case, I'm not sure. Definitely not qualified enough to answer something that complex.

[@greggh]

I learned about the double slit experiment in high school and then again in college. I never understood it as well as from your presentation. Thank you.

[@digitallair3425]

I was thinking the same thing. High school, then college .... errrr.. ok...huh? Now this video -- Ah I've got it!

[@haydnrogan6789]

I was just remembering doing this experiment at uni, I remember the girl I was doing it with and that's about it lol

[@schrodingerscat8391]

Same here i study this in highschool when i was 16 yrs old and now i m 28 a doctor but still haven’t understand this

[@tony_1980]

@@schrodingerscat8391 You covered quantum mechanics and the double split experiment in high school? Some high school you went to. I went to high school in Norway, and when I studied in the US at University, the math class my year at University in the US was high school level in Norway. So color me impressed of your high school.

[@skulqerX]

Also learned the young double slit experiment at highschool. At the time it was only referring the wavelike pattern so no biggie. 10 years after that the same experimet cropt up on my feed and said it was one of the explainations of quantum theory .# My whole life is a lie

[@grahamyodude]

I can explain this easily but I don't want youtube people stealing my Nobel Prize

[@yassineselmi7714]

me too

[@empty2110]

grahamyodude it’s quite simple my good sir 🍷

[@peteq1972]

Tom Campbell has it licked in his video The key to understanding our reality.

[@Valorince]

watch him say God

[@47571660]

The margin is too narrow to contain it.

[@TheRealestBubby]

This issue is what sparked my everlasting curiosity in physics and quantum mechanics, just to fall down a rabbithole of hundreds of weird and confusing data from experiments that classical laws of physics just cannot explain. there's just so much unknown, and so much to discover and learn. This specific problem in quantum mechanics not only gives plausibility to an observers universe, but also in certain specific scenarios, it fully implicates direct time travel of photons as a normal working part of the universe

[@biokudde]

Same for me! Any other particular experiment you would recommend I look up?

[@Bigdiccdaddy]

@@biokuddedid you find any? Im curious too lol

[@simonfintzstein5199]

I don't know much about science, it wasn't my easiest subject growing up. I am just beginning to learn about quantum physics. Some videos I have watched on this experiment, and I couldn't quite comprehend what was going on. This explains it so very well in an easier to comprehend way. Thank you for this video.

[@dr_jaymz]

in a way, quantum physics isn't very good at science either - because anyone who thinks they understands it, doesn't understand it. And by definition, quantum physics is very much not classical physics, and therefore not being good at that to start with isn't a barrier. Quantum physics in essence is anything that logically doesn't fit with any everyday knowledge and experience.

[@3brenm]

​@dr_jaymz it's good at stats, but bad at theoretical physics. But everytime i watch the double slit experiment again i just get blown away again and again by it.

[@ayezz2811]

Stay curious Simon!! 🙂

[@kviehdor]

"Quick, the Sims are becoming self-aware!!!!" Expect a software patch shortly.

[@Gcammo]

Kurt V haha 😂

[@grahamyodude]

They tried patching it last week but I remember this happening last week so looks like the patch update failed

[@danpoole9016]

@@grahamyodude I'm from future. What happened last week

[@manawearblack]

It will never be patched, because then we would all realise that we are definitely in a simulation/computer program

[@ludik2312]

The COVID-19-restart-required patch?

[@GamesBond.007]

First of all, I would like to thank Jim Al Kapone for making this Nobel prize possible. Second, I would like to thank the atoms for being so confusing. I also have a split personality and thats why I can get in their mind. Its not easy to be an atom. You dont even know if you're a particle or a wave. Sometimes you behave like a particle, but sometimes you behave like a wave. And last but not least, I would like to thank me for being made of these particles waves. *Waves at atoms. Atoms wave back.*

[@Mystical3030]

Wow...so profound!!

[@jucklowe]

Swing and a miss.

[@russcooke5671]

As made as it seems in black and white it’s does make sense

[@stephaniasanchez-tarre3604]

Thank you for the unexpected laugh lol

[@aeonsleo2]

That's intellectual venom

[@mynameismaciek]

My layman's theory: Photons generate very subtle gravitational waves in which they themselves travel. To prove this, one can try to disturb this wave with another device. The photon detector might actually interfere with this wave, which is why the result of the experiment is surprising.

[@qaesarx]

No, still doesnt make sense, the detector is looking at only ONE slit, still the second slit is affected too. Also the detector is passive. And even if you unplug it, it will receive the energy but dont record it. Also ALL the atoms are shot one after another... The only explanation would be that space has a structure that guides the atoms. And that structure is becoming deactivated by the detector... the question is, WHEN. When WE look at the result or when the detector looks at it... If its about US (way later..) this would mean that the space has somehow temporal determinism or the atoms do... its weird anyway...

[@steviesteve750]

You might think that the universal laws of thermodynamics apply here, after all to detect an atom, or "see" it, that requires an interaction with a photon, this changing it's energy level; a bit like using a contacft thermometer, which immediately changes the temperature of the surface once it's in contact, as the thermal energy rebalances locally. The issue is how does this interaction change the slit pattern?

[@TheRetroGamerReese]

I agree with this and was going to post but was hopeful there was another person who saw it this way. Bravo go collect your nobel prize 🎉

[@darkesco]

This is absolutely how it works. The observation device disrupts and, therefore collapses the patern. If we could detect a photon or electron without altering its state, we could theoretically have instantaneous communications between devices from one galaxy to another. The atoms do not "know they are being observed," like many experts say or allude to. It's just them witnessing to you about their silly simulation religion.

[@RichardWebb-do6cw]

Nice glitch in the matrix if you ask me. Humans 1 creator 9999999999999😂😂

[@derpy._.josiah7985]

Bruh I started from a physicist reacting to Attack on Titan and now I’m here😂

[@DaveZeke]

Hahahaha same! Except it was him reacting to Rick and Morty and also referencing this.

[@terencenjoroge463]

me too but from rick & morty

[@gabrielcornelia9995]

Ha ha anime working wonders

[@bro0ke_lyn794]

I started from a tiktok where a woman criticized religion and now I’m here ;-;

[@terencenjoroge463]

@@bro0ke_lyn794 i do not even wanna know what happened in between lol

[@mirrorimage5423]

"Described" rather than "explained".

[@ayingchanda]

Both are the same tbh but i agree with you

[@danpoole9016]

Because it's a mystery, we can't explain why it happens.

[@sickduck9865]

He explained the EXPERIMENT not the phenomenon.. smh..

[@widjadija]

I think you read it as “the results of the double slit experiment explained” when all the title implies is an explanation of the experiment itself, which it did.

[@johnc3403]

Duh! ....explain it and the Nobel prize is yours!

[@christopherscallio2539]

Eureka! So that's why a watched pot never boils!

[@kalebrand]

I actually debunked this in 6th grade for a science fair. Watching the pot takes the same amount of time, but it generates boredom as a byproduct

[@doktormcnasty]

I make a point of watching every pot of every liquid change to the boiling state just to feel the satisfaction of putting it to everyone's face who repeats this nonsense.

[@jitheto551]

Boils but very slowly

[@manawearblack]

@@doktormcnasty You're taking too seriously fella, the phrase means that things seem to take longer when you watch it, kinda like how if you watch a clock for 5 minutes it will seem to take much longer than if you just watch a 5 minute video on KZbin or distract yourself some way

[@doktormcnasty]

@@manawearblack You know what, if you don't mean it then don't say it. Why not just say "It seems to take water longer to boil when I'm watching it"? Why's that so hard? Why do people feel the need to get all hyperbolic with words like 'never' which are obviously completely untrue to the situation?

[@tombrunila2695]

I have watched many of videos with Jim Al-Khalili, and I can say that he is very good at explaining complex things. Very much like Jacob Bronowski, James Burke and Carl Sagan.

[@akgreengirl9876]

And dear Richard Feynman

[@danielpaulson8838]

And Brian Green

[@beryllium1932]

He physically resembles Robert Andrews Millikan.

[@PHOTOGRASPER]

"Nothing is exactly as it appears, but everything is exactly as it is.. " - B. Bonzai

[@greggrobinson5116]

Or, as President Eisenhower once observed: "Things are more like they are now than they every have been before."

[@vinojoshua841]

And God saw the light, that it was good... Genesis 1:4 Jonah 3 10 Then God saw their works, that they turned from their evil way...

[@bab008]

I've heard this explanation: So long as quantum particles do not interact with anything in the universe at all they act as waves. But as soon as they do interact with anything they take on particle like behavior. Every detector necessarily relies on some type of interaction with what is shot through the double slit in order to detect it. So, in this example unplugging turns off that interaction.

[@manoj81478]

Have you heard of "delayed choice quantum eraser double slit experiment"??? If not Please checkout and explain to me with logic..

[@takisk.7698]

ppl buy into the "spookiness" of quantum physics so easily.. while there are perfectly reasonable and simple explanations out there.. makes me pretty disappointed on my fellow human beings.. we are smarter than this if we just try a little bit.. come on now.

[@popcorn2466]

@@takisk.7698 obviously everyone there know there's an explanation.... the point is with our current knowledge we are so far from understanding it that it ''currently'' is magic for us

[@takisk.7698]

@@popcorn2466 there's way too much that we don't know and that's okay but when you get some unexpected results and you default to supernatural nonsense like "the human conscience affects the quantum world?!" instead of going with logical explanations.. it's just disappointing to see.

[@popcorn2466]

@@takisk.7698 true

[@sagarsharma3653]

Jim Al khalili is my favourite when it comes to quantum mechanics. I just love how easily he explains such complex things.

[@schmetterling4477]

Why do you love false explanations?

[@joxyjoxyjoxy1]

Technically, he failed to explain something.

[@schmetterling4477]

@@joxyjoxyjoxy1 Yes, he failed to explain the actual physics of it. ;-)

[@dwaynekeenum1916]

@@schmetterling4477u dumb , by ur logic explain the physics of God or a lack of God

[@dwaynekeenum1916]

@@joxyjoxyjoxy1L

[@stevenantalics31]

As commented by some, I think what we perceive as atoms (just like electrons) may exist in a quantum cloud that's governed by higher-dimensional laws than we can detect. However, our detecting equipment may cause some tiny variations in those dimensions that account for this behavior. Figuring that out is obviously non-trivial, but imo that's where the answer lies.

[@sentientbean1]

If the tree falls in the woods and no one is there to see it, has it really fallen?

[@MsTringan]

Does the world exist before you Open the Door?

[@nabuk3]

Yes, that seems obvious, so why didn't Kalilli address it??

[@TheRoyalInstitution]

You can now enjoy this mind bender in Spanish, thanks to a kind person who donated their time to provide us with Spanish subtitles. Gracias!

[@griffinfloyd]

The Royal Institution is it possible that the device used to sense the particles was interfering in some way... magnetically or electrically? and that that caused them to behave differently

[@NinjaWarriorDude416]

Witchcraft.

[@HG-Pilot]

You are on the right path my friend! So now The Mental Institution can mislead and confuse Spanish viewers as well! Watch The Primer Fields Theory 1 - 3 he goes into a great details about why all this is a new age BS. We are not allowed to go into higher energy physics and thanks to above bs is not going to happen any time soon.

[@notdaveschannel9843]

Lo siento, no entiendo. ¿Cómo se dice en español?

[@promoteamutube]

Please remember that this is not a mind binder. I can give myself the Noble prize if you want but the explanation is so simple. The problem of course here is that scientists still think n term of electricity and magnetism as either wave or particle. They have not yet put feet n the other forms of energies that compose this duality of electricity and magnetism. If only they understood that thoughts are the creators of this duality, they would understand their own experiment. They still fail to understand how consciousness impact its own creations. They still don't understand the two impulses that manage this manifested expression. Time will come. I explained this mind binding illusion in simple terms but look into how consciousness create reality via its 2 impulses and you will understand why the camera impact on this experiment. No need to be a scientist, you see.

[@Drummerdude998]

Maybe the detector gives out an interference of its own which changes the way that the electrons act?

[@2222badger2222]

what about when the electron goes though the bottom slit ? the detector isn't required

[@Drummerdude998]

***** chill out, i'm just making suggestions xD

[@ThatOneScienceGuy]

I was wondering the same exact thing. This is the only logical explanation. I can only assume this has been ruled out as a possibility, and if so, I'd like to know why.

[@Drummerdude998]

***** oh soz mate

[@PR0Z0MBIE9877]

it actually does seem like that lmao

[@kivvx4134]

he's wearing a bowtie which helps me focus more by about 5%

[@liberationwasalie2982]

😂😂😂

[@sephblack]

Yeah but it's also +5 RADS

[@Mark_Agamotto1313_Smith]

Well of course, Bow Ties are cool, just ask Matt Smith.

[@posthink6166]

oh God, if you get affected by these small things, then for sure you are distracting freak.... :)

[@ManoukRoussyalian]

It's fascinating that we chose to focus more on determining the cause of an action rather than trying to understand its meaning. From my perspective, this experiment suggests that atoms seem to change their behaviour when they become aware of being observed. What could this signify? If you choose to ignore them, their future remains the same; however, their behavior shifts once they are aware of being observed. Does this imply that each person, as an observer, possesses the ability to impact their own reality, which is essentially composed of atoms that may or may not be influenced by the observer's attention?

[@kujojotarostandoceanman2641]

Nah you just no good at quantum physics, this is about information not about observer

[@kujojotarostandoceanman2641]

Quantum mechanics is not about observing it's about information can interact with eachother ignoring time itself, future info can change the past

[@Langkowski]

Forget the whole concept of observing.

[@schmetterling4477]

It mostly signifies that you weren't paying attention in high school when this was explained to you correctly. ;-)

[@TheAcolossus]

All future Nobel Laureates in the comment section

[@ranichoudhary1989]

Hahaha

[@mudza92]

But jut what, just imagine, what if one of those commenters is the one capable of solving this mistery, and is dehumanized by ordinary youtube commenters disgusting behavior, and actually never look back at this double slit experiment again. Yeah we humans deserve to be wiped out of egzistence

[@techdesigner9741]

Solved it: our thoughts create waves (brain activity can be measured through frequency) therefore when we're observing we're emitting waves and the particles are simply riding them 🏄‍♂️

[@0i0l0o]

@@mudza92 relax dude. your resintment for humans has nothing to do with his briliant comment.

[@mudza92]

@@0i0l0o That's briliant to you? You are very easily amazed lol

[@fo1k1ore]

"No fair! You changed the outcome by measuring it!"

[@sazennonumber]

Love Jim Al-Khalili. This was a great video, cannot believe I never discovered it before.

[@Dragondave17real]

1. The behaviour of atoms going through the slits is the same as the behaviour of light, for whatever reason (e.g. maybe something is altering the behaviour of the atoms, or maybe some assumption about the behaviour is incorrect). 2. The detector interferes with the results. E.g. a detector could cause the photons to go through each slit with a 50% chance, whereas the absence of a detector could cause them to go through both(somehow). 3. The detector being activated or deactivated is a determinant in whether or not the results get changed. Even if that doesn't appear to make any sense. Maybe it changes it in a way we just don't know about yet. To me that's the most rational explanation even if we don't know how or why. Haven't they done an experiment where they put a filter on one slot as a method of detection and the thickness of the filter effected the result of the spread?

[@Ellie-jw3mr]

I just read Rovelli and have some thoughts about this. According to loop theory there is no such thing as a global time but the "mark" of events/processes. What does this do to the double slit experiment? Could it be that the probability wave is not collapsing because of the “record”/ obvervation, but rather that there is no particle, just a sequence of an event? That the future and past is indistiguishible if there is no “record” ie no “foot print” of the photon traveling towards the slits? So in other words there isnt a wave that collapses into a particle, but rather a series of probable events which are all leaving a mark and dont exist as eigher particles or waves. The particle is the event. When we mesure it, it doesnt collapse, but we just measure a point in this event sequence? When it has leaft a mark/footprint/has been measured it stops behaving like a “wave” because it gets a past and therefore its future is limited. What do you think of these thoughts? Is it just an uninformed thought of a non phycisist or am I just saying the same thing but in other words? ^^

[@todoelmundoapesta]

Sounds like not recording allows for us to have a small glimpse of multiverse posibilities as if the experiment moves through 5th dimension but shows different paths, once we record, the gate allowing us to observe multiverse through 5th dimension closes, hence no more interference pattern

[@generalruler]

I I think your thoughts are nice, I think they may have been informed by several physicists, because who else would make seemingly normal words become an abstract concept that is by human standards relatively inconceivable. I think it depends on how many slits were open when you sent the thought particles in to the comment field, but now that I've waved them through they might get a new future ripple into the slits that I may/may not be recording;/observing despite the inherit pretense of the wave's literal unobservability (adds triple word score) Perhaps you could experiment by saying the same thing but through other slits and the see if the result results on the "mark" but in actual words, I hope they do, not theoretically, with actual processable words though. What do they think do you think? thanks in advance. Ham.

[@r.gelmers6580]

Very similar to my thoughts on this effect. I think it's a natural mechanism to guard the laws of causality. Both interaction and information collapse the wave function because at that point, the particle becomes part of the chain of events.

[@curtismaize]

The atoms are having a party and we're not invited, so when we call them to see what they're doing they tell us they're just chilling at home. I think we just need to understand that we're not cool enough to hang out with atoms.

[@princemateosparta5882]

Like UFOs. They are more free and open when we are unaware of them but once we prepare the detector equipments they are gone

[@111sushant]

As far as I am concerned, it was difficult to work in the same relaxed way in the office when the boss was standing at the back of my seat and observing what I was doing compared to the moments when no one was observing.

[@sampsontendaimutsago1935]

True

[@Jagamy]

That’s because when he was there you were working and when he he was gone you were on the internet watching clips like this.

[@vinojoshua841]

And God saw the light, that it was good... Genesis 1:4 Jonah 3 10 Then God saw their works, that they turned from their evil way...

[@VincentVendetta80]

very good analogy

[@davidbristoll195]

It'd be interesting to know more about this. How did the sensor work? Did it emit any waves or particles itself? What different detection methods have been used and what were the results? This was 10 years ago, is it still considered that the atoms somehow change their mind?

[@XENONEZZ2]

I was thinking the same....it could be the detector interacting with the atoms that produces the results seen.

[@Morethanamethod.]

Wouldn’t all these genius researchers also pose that question?

[@davidbristoll195]

@@Morethanamethod. I'd have thought so, but, I'd also expect them to talk about those questions too and they haven't.

[@rc6115]

That's a very very good point. Didn't think about it....

[@willhamilton2467]

I believe that this is stiill the most accepted interpretation. I believe that cameras work by light wave/particles affecting the the recording part of the camera.

[@kadalijo2806]

'Do you really believe the moon is not there when you are not looking at it?' - - - Einstein

[@Dailyplanit]

according to this science its always there just sometimes as an energy wave and sometimes as a solid mass. But when is the moon EVER not looked at with millions of species crawling about the planet?

[@gamedeveloper_1999]

This is a theory. There is not proofs about it. This theory uses in the games for optimizing the game. Just render where you look at. We do not need to render the back view scene in the game for optimizing the game. The world is not video game and then there could not be such as this theory.

[@doji-san]

@Fida Muhammad When you asked your friend you effectively transferred the vision to him so you ARE EFFECTIVELY looking at the moon. Now if he is also not looking at the moon and he tells you it's there, then he is lying to you :D

[@johnmoore4523]

Prove this to yourself, sit quietly,clear your mind, close your eyes, close your mouth, close your nostrils, give it half an hour and then ask your self what really exists. Then try this for 3 hours!!!

[@erbalumkan369]

I am looking at the moon where it was about a second ago.

[@jaydonnolan6023]

Explanation: Atoms are actually aliens in tiny spaceships who like to confuse humans. Noble prize please!!

[@br7078]

+Avi K LEL

[@gurjantgill8681]

+Avi K You sir have just wrecked this kid hard. I guess you deserve the Nobel prize...

[@hunterwillis7283]

Jaydon Nolan i was just thinking something along these lines! lmfao or! or! or!... reality is trying to keep us from realizing thr truth, that truth being that all of reality doesn't truly exist, and reality conceals this secret with superposition. ;)

[@LordSaboLP]

i refuse to believe this isnt the right answer, for me...thats how it is now thank you.

[@brentlio5578]

Why so complicated? They are just trolls.

[@misstaniamaryam]

Thank you Sushant Singh.. Learnt something new today

[@crazyshitgaming]

Hm

[@shilohaapala284]

Best explanation out there. Made me finally visualize the two slit experiment. Unplugging the detector boggles the mind. My thoughts. When you take a measurement. You are making a call on energy much like a computer operating system to generate physical reality. When you unplug the measuring device whether you like it or not you have made your intention clear you no longer intend to take a measurement and reality corresponds accordingly.

[@ronanmcw]

More boggling for me is that when the detector is plugged in it's only observing the top slit, not both, and atoms are only being fired out one at a time with a gap in between. This means atoms passing the bottom slit are both not being observed and not being influenced by a previous atom - why would these ones not form a wave distribution pattern? In those instances, the act of observing *literally something else and not the atoms in question* is causing a change in behaviour, which is just whacky.

[@badlydrawnturtle8484]

It bothers me how when describing the double slit experiment, they nearly always gloss over the inner workings of the detector. Since we're dealing with individual particles, it's kind of important to know what the detection method is so we can know how they are or are not interfered with. In this video, for instance, it is utterly un-awing to me that the interference pattern comes back when you turn off the detector. If it is in any way an active detector rather than a passive one (think bouncing a second ball off of a first ball to figure out where it is, vs looking at the track left behind as it rolls), then turning it off is essentially backtracking to the experimental conditions that produced the prior interference pattern, so of course you get the same result.

[@badlydrawnturtle8484]

ohemgee That's the problem, isn't it? An instrument effect is the most logical conclusion to draw from the double-slit experiment, but videos like this (and indeed whole communities, including seemingly many physicists) are trying to argue the exact opposite: That it isn't an instrument effect; that the “observer effect” is a separate concept that involves some sort of knowledge transfer rather than an interaction of physical states. You can see that this is what they are trying to do when they put in the detector and the interference goes away; and then they turn off the detector without removing it and say “Look, the interference comes back! It must not be because of the detector!” If they thought it was an instrument effect, the final round of oohs and awws wouldn't happen. Hence my comment about active vs passive detection; the way videos like this treat the experiment only makes sense if it is a passive detector, since turning off an active detector is effectively removing it. (It becomes even more troublesome when you know that passive detectors at the quantum scale are pretty much impossible.) I guess I'm less confused about the experiment than I am about people's reactions to it. Why do they think this is impressive, let alone a world-shattering paradox? I feel like I'm missing something by not finding it as baffling as all of these scientists make it out to be.

[@badlydrawnturtle8484]

ohemgee I think this guy honestly believes that there is something other than instrument interaction going on. I don't have any direct evidence of a large number of physicists thinking that way, but I get an impression of it from the phrasing that goes with this sort of experiment, even if the person talking is otherwise competent.

[@Goohuman]

Badly Drawn Turtle The reason we don't hear scientists refer to the detector is because it had the same effect on the experiment in both cases. Without changing a thing, the experiment was done recording and not recording the information. Believe me, this experiment has been repeated many times and by much smarter people than you and I. Detector interference was the very first thing they tested for. We are beyond that now. But there is a logical answer. It just doesn't apply to a strictly material world.

[@badlydrawnturtle8484]

Goohuman Yet, I have yet to find any reliable source that describes such an experiment with adequate attention to the detector. In other words, I don't believe you. Not without sources. A strictly material world is all we have evidence for. Postulating non-material answers would require a lot more than one type of experiment; it is an extraordinary claim that would need an extraordinary reason to consider it.

[@Goohuman]

Badly Drawn Turtle I get it. You are not willing to consider non-material causes. I put it to you that the results of this test are pretty extraordinary. If you are seriously questioning the detector, then you owe it to yourself to look into the actual research that was done. en.wikipedia.org/wiki/Double-slit_experiment You may also be interested in an even newer version where the observation is made after the photons have passed through one of the slits and before they land. Quite fascinating: en.wikipedia.org/wiki/Double-slit_experiment#Delayed_choice_and_quantum_eraser_variations

[@ujLion]

I wish this challenge and admission that "we don't know it all" was written in my text books when I was studying..

[@mangaranwow2543]

Atoms are the same as humans, when they know that they are being watched, they act different. :D

[@ramtinsharaf2416]

No, humans are made of atoms

[@jamesstevenson7725]

lol

[@moneerkarim7809]

This is a very good one

[@Dracopol]

The "observer" in quantum physics is not a human being.

[@jamesstevenson7725]

But if a human being did observe the particle, it would still behave differently if it was being watched

[@caboosej8749]

so if anyone ever asks you if supernatural things exist just point them to this experiment.

[@thanamelessone2948]

What do you mean?

[@KreeZafi]

It genuinely upsets me when people without much knowledge about physics are trying to explain why this is "bullshit" using their own assumptions. I'm sorry, but do you really think that you can figure out what those with a PhD in physics can't? That's like choosing whether to listen to a meteorologist or a psychic to tell you what the weather will be like tomorrow. Surely you must believe the one who has extensive knowledge and performs tests to find out facts?

[@supersonic174]

KreeZafi that's true but, whats going on in these experiments like with quantum entanglement is foreign to physics. Like for example this guy Jim Al-Khalili has a PhD but does not understand whats going on in this experiment

[@KreeZafi]

Aweri Blakely That's what I said. If people with massive knowledge about physics don't get it, how come amateurs without that knowledge believe that they have the answer which professionals can't find?

[@taylor17587]

KreeZafi Because having multiple viewpoints can spark new ideas, which leads to new experiments, which leads to new answers.

[@tomhardwick3801]

I agree we can't let them meteorologists go telling the weather, the rapscallions!

[@MarshallPFinch]

KreeZafi I recommend reading about the Dunning-Kruger effect. Those without skill don't know how little skill they have!

[@feverkane]

Love prof. Jim. His 3 part series 'Atom' was life changing for me.

[@williamdekker]

Watching that next, ty for the rec

[@feverkane]

@@williamdekker enjoy

[@Red-Brick-Dream]

Same bro. Still gives me goosebumps.

[@cheriereiner]

Make it 3 slits to confuse them 🤣

[@David-bc4rh]

block all the slits turn out the lights exit lab promptly

[@davelordy]

@@David-bc4rh Don't forget to lock up the atoms first, you really don't want to leave them loose in the lab, I use a shoe box.

[@Mysixofnine]

Or remove the slit and place a hair.

[@Mysixofnine]

@Tanaphar Plus Masks what’s waving? Aether? I don’t use the same mechanism everyone else’s uses for light. I use another assumption.

[@Mysixofnine]

@Tanaphar Plus Masks so the question is, why to we see fringe pattern on the wall? We have two hypothesis, on a “wave” two a particle. Can we assume of a third hypothesis that mediates light?

[@Ventus277]

How do we exactly "observe" the atoms. As far as I know you have to hit the atom with another particle to "observe" it, right? Isn't it more of a "skill issue" since you can't actually observe them without interacting with them? What I'm saying is that our unreliable way of "observing" the atoms is changing their behavior since we're obviously interacting with them?

[@VincentVendetta80]

obvious thing - even for a complete idiot ... I'm not sure what is so strange about this

[@c.s.hayden3022]

It’s often given a sort of magical interpretation where just looking at something can alter the outcome. More like coming into contact with anything will always distort it to some degree.

[@takisk.7698]

Bingo.. there's no way to "gently observe" as the presenter puts it.

[@nmarbletoe8210]

@@takisk.7698 Gently doesn't mean without influence

[@takisk.7698]

@@nmarbletoe8210 it's a misleading word to use.. the detector interferes with the result so there's nothing "gentle" about it

[@esfbse8347]

@@takisk.7698why would a wave function collapse when it is measured

[@zoranvelickovic8814]

Double Slit : Why does a wave collapse into particles when you trying to ( change energy state ) observe it? Because you are directing energy from that same wave by observing ( you are putting energy in one point - action is reactive - it's explaining superposition ), and that causes particle. You get what you do, not what you expect. Delayed Choice : How does a particle know what to do before other reach the detector? Because they are also entangled with time (you must include everything if you want to define if something entangled which include time also). This all make more sense if you approaching problem from a quantum field perspective, Of course, it's need to be proven first.

[@xEvilRaptorx]

Wouldn't this experiment, in a way, explain that Life exists to observe. If not observed, it is like Schödingers Box...

[@zoranvelickovic8814]

@@xEvilRaptorx I don't believe that cat is in superposition until you open the box and see result. The amount of reality on that scale is already too much complex. We do interact when observe but only with energy needed to create our observation. But on quantum level things are very sensitive and even by thinking we already change something.

[@coolbeans5911]

I don't know anything physics and have tried reading up on this experiment but could never really understand it and why it's so famous, but now i have a much better idea!!! Wonderfully explained and thank you so much!! It's so cool and weird😂😂 atoms are sneaky

[@SunShine-kd6td]

Veritasium did a much better video.

[@tony_1980]

@@SunShine-kd6td If you think that. you don't understand the problem

[@promoteamutube]

Not really sneaky my friend. The atoms and molecules themselves possess kinds of consciousness impossible for you to analyze, because the scales of your activities are so different. They are information-gathering processes, however, containing codified electromagnetic properties that slip between all of your devices. The atoms and molecules and all of the seemingly smaller "particles" within them are, again, information carrying processes, and upon them depends your entire interpretation of the nature of events.

[@j.p.5617]

@@promoteamutube gathering information for reality?

[@captpicard100]

It’s perfectly easy to explain:- The contra-di-fabulating trans-denominating upper and lower oodle Flori-murdle-bunds are all explurjigating in an anti-clockwise Oodle Splunge cloud. I thought everyone knew that.

[@timothytumwine670]

An explanation of how the observing apparatus works would be helpful

[@sickduck9865]

thank you

[@David-bc4rh]

it's all very small of course, but it's just an electrode that's tuned to detect the micro current of electrons or photons. There's other ways to get particles to move a needle, but to count single photons passing through a slit, this is all that's needed. old tech.

[@benitocamela6336]

Does it really need an explanation though? It's based off of emitting a certain frequency that will detect the atom or some individual particles that compose it. I'd like to know what you think about the comment I made recently in this video. Sorry I can't provide you with a specific link though.

[@bokchoiman]

@@benitocamela6336 Not everybody understands everything without having scientific background.

[@VincentVendetta80]

it doesn't matter how it works. its completely irrelevant. what counts is that either it works or it doesn't. meaning either interfering with particles or not. one pattern device on, another pattern device off.

[@alabamasteve8748]

I understand the experiment ,but there are several things I am curious about that I haven’t seen, experiment with or asked about . The width of both of the slits , the material used , wether it is a reflective material ( has it been painted with a gloss , semi-gloss, satin ,etc. What happened when you simply take a camera flash at them? How close are you shooting the photons at the slot , what happened when you back up . What if the slits we’re sloped outward like as if the slits were coming in (within the width of the material containing the suit) like this < ,(get what i’m saying ?) and finally what if you shoot the protons at the slits with slit cutouts on the “proton projector”, or light producing object, therefore aiming at the slits alone and not at the entire board. And then changing them to aim at just one , have those been tried . What if sound is being playing at them, or different frequency waves ,tones. Finally , what if you power up the light and shoot it at the slits , like more or less directed lumens? Would like to see these done and also the questions answered if known .Please

[@schmetterling4477]

Why are you telling us that you don't understand the experiment? ;-)

[@tylerslepicka156]

is the electrical current that the detecor uses to measure the photons putting out a magnetic field ? or something like that

[@CarolanneIAMTHEQUANTUM]

I love telling everyone know about this experiment. I have for years. Mindblowing. I love quantum mechanics.

[@SYNTAX_ERA]

Its like we create our own reality. The universe behaves normally when we are watching it. Glitch in the matrix there 😃

[@donaldkasper8346]

@@SYNTAX_ERA Yeah, other than the particles have electric fields, interacting with matter with a slit in it, with electric fields, observed by a detector that has an electric field. These are not particle experiments, they are field on field experiments.

[@randomme6954]

has there been an experiment set up for the double slit, where there a sensors at each level. And if each sensor (2 gaps, 1 wall) receives a ping over time, could we attribute the wave appearance to the gravitational influence on that photon at time of observation?

[@williamb7275]

I am wondering the same.

[@owninghappiness]

This was such a GOOD video. Understanding this experiment was very difficult, & you nailed it in one shot !

[@johnnyc.31]

You only think that he nailed it in one shot, because you were observing! If you didn’t watch this video, it definitely would’ve been two shots.

[@kanalbenenner7830]

So, how does one creat a particle pattern, if I want to do it at home, how would I do that?

[@jimbrewer5048]

Ur comment deserves more love. Very clever

[@heingrobler9382]

This might explain how you can "feel" when someone is looking/staring at you..

[@dyinginsidelol]

It’s a survival instinct

[@aliasanonym9778]

You can't. People start experiencing the "I am being watched"-feeling because - for example - the room becomes awkwardly quiet.

[@jesserodgers3759]

@@aliasanonym9778 not at all man I’ve on many many situations through out my life just for no given reason looked in a particular direction that happened to be exactly where someone was looking at me and I have had the exact same thing happen when looking at someone else. In multiple different loud and busy situations as well like a bus a coffee shop the mall.

[@zwan1886]

@@jesserodgers3759 and there were many more times where you didn't observe the person watching you; you only remember the times where you caught them

[@kilaa3417]

@@jesserodgers3759 Yeah, it's amazing that we sometines just have a "knowing" about being observed, as we do with intuition

[@ianbortolotti6520]

We might be careful of using the term "explained". Quantum Mechanics is a bit like having to guess at the right question after being given the correct answer to "something".

[@neilgibbons2532]

You mean like proving the proof 💁‍♂️

[@isatousarr7044]

The double-slit experiment beautifully illustrates the fundamental principles of quantum mechanics, demonstrating the wave-particle duality of light and matter. It's fascinating how particles can exhibit both wave-like interference patterns and particle-like behavior depending on whether they are observed or not. How does the observer effect in the double-slit experiment challenge our classical understanding of reality, and what implications does it have for the nature of consciousness in quantum mechanics?

[@lepidoptera9337]

Wave-particle duality is not a principle of quantum mechanics. It's just an old (and false) meme that doesn't want to disappear.

[@max20817]

can the detector when switched on be causing some sort of involuntary interference with the atoms

[@SurreptitiouSurprise]

I'm certainly not proficient with physics, so I'm probably about to sound really dumb. So a photon is a wave particle, but because it travels at constant velocity, it has a zero resting mass, yeah? But we know atoms do have resting mass. First question is: do researchers get the same effects if they send just one photon at a time through the two slits as they do when they send one atom? Second, can the difference then mass between the two contribute to the differences in the outcomes?

[@bme7491]

The detectors are actually photo-multipliers, they don't "shoot" light/photons onto the particle.The more sophisticated "delayed" two-slit experiment shows that if you know the path of the photon (by which detector it hits), it will act as a particle. If the path is not known (possible two paths), it behaves like a wave. Really weird.

[@bme7491]

They've sent everything from photons to Bucky Balls and the results are the same.

[@bradleyearl7257]

Interesting! Truly mind boggling stuff. How do the photo-multipliers work?

[@bme7491]

ConsciousConversation They are basically multi-stage amplifiers, converting the photon into an electrical signal large enough to be analyzed and processed.

[@Treefrogging]

My god, that is unbelievable. Stunning explanation

[@techdesigner9741]

I've watched many videos on this experiment and what I don't understand is how do the particles pass through the slits? Don't they travel in a straight line? Isn't the source centered and therefore the particles would simply hit the center of the barrier, i.e. material between the slits? Wouldn't the source/laser emitting the particles have to be angled for the particles to pass through one slit or the other? For example, if we replace the particles with tennis balls and the gun projecting the balls is centered relative to the barrier with the slits, no ball would go through, they would all bounce back. Your input would be much appreciated.

[@TwinbeeUK]

I assume the slit is very very close to the other slit, but this is also frustratingly not elaborated on.

[@Playboyy1985]

It’s because they “travel” like a wave.

[@AxelNorenburger]

I hate how they never mention that the detector is something that has to interact with the atoms, which changes the the state of the wave.

[@Malin0908]

Yes, like conciousness. Is conciousness creating our reality because it interacts with The atoms snd therefore creates reality? It change The state of the wave because it is able to observe it.

[@chriswilkins2643]

@@Malin0908 your the first person out of a number of comment I have read that is near the mark of what's going on. Most just cant come to terms with anything that's not physical

[@Malin0908]

@@chriswilkins2643 i take that as a compliment, yes?

[@chriswilkins2643]

@@Malin0908 yes , you can

[@Malin0908]

@@chriswilkins2643 Thank you

[@xGOKOPx]

Pity he didn't explain that observing is not passive. In order to detect a particle you have to hit it with another particle. So by observing the atoms you interfere with them

[@mojkanal9519]

they never do. They always pretend that atoms have some sort of telephatic powers.

[@nihatnihat8264]

Yeah, I was disappointed he did not explain that. I think it's because they think it looks cooler when they don't.

[@geekinasuit8333]

​@@nihatnihat8264 it's a lot more entertaining to leave the interaction detail out, makes it seem "spooky" as if the particle/waves can "see" if someone is looking at it.

[@geekinasuit8333]

@Donald Piniach I'm interested, maybe information has something to do with it, information is sort of like QM, it's very hard to understand. Your words require a definition. What is precisely meant by "delayed" and how is the information "sampled"?

[@geekinasuit8333]

@Donald Piniach Very interesting for sure. After looking at the erasure experiment several times over using various sources, it's kind of like a magic trick, where you distract the audience by having them all focus away from the obviousness that exposes how the trick is being performed. The obviousness in the erasure experiment, is that the screen itself is a detector that interacts with and therefore is able to influence the behavior of the entangled photons being detected on the other set of detectors, including the one that supposedly erases the "which way" information. It appears that all that was done, was to make the double slit experiment considerably more complicated without actually doing it any differently, i.e., we've simply relabeled one detector " the screen" for another "the detector". I do like what you suggested about the "observed" behaviour having something to do with "information", because to this point in time, I've not yet found a satisfactory definition of what information actually is, despite spending a lot of time studying the concept. Usually when it's hard to pin something down, it's because the word that is used is "loaded" where as it relates to multiple things all together ambiguously, the challenge therefore becomes how to identify and separate all of the different things out so that they each can be understood individually.. The reason why I'm looking at QM concepts, is while trying to sort out the concept of information. I actually find QM simpler to understand than the concept of information, that's not saying that I think that QM is not complicated, it instead appears to be better understood at this time than the concept of information.

[@justlikethatnowadays8454]

Finally a clear video on quantum physics that directory tackles the subject without rambling

[@severe28]

Great lecture. Probably the best explaining the Double Slit Experiment..

[@CarlWinter-oy8uf]

Have been avoiding this freak show for 40 odd years --but Mr Al Khalili has a brilliant method of getting this phenomena across to dodos like me --thankyou Jim !

[@rakeshshah5032]

My kitten behaves in the same way. He stops playing as soon as I start filming him !

[@harisnh1366]

Does your cat happen to be a member of Atom Cats?

[@philippizza1]

Show him what happens to schrodinger's cat, and let's see if he still acts that way

[@ShayNescu]

lol!!

[@jk1776yt]

Every time I hear about this experiment it blows my mind! Every time. This was a good simple explanation of the "mystery"!

[@adamreecepiano]

but see comment by Jako above with possible explanation

[@promoteamutube]

There is no mystery my friend. “the observer is a part of the experiment, and the results will conform to the expectations of the observer”. By viewing the double slit experiment as not just an experiment, but as a reflection of the observer’s own experience, we see how our own expectations and beliefs can influence our reality. The "particle" itself is just information and has nothing solid. If you can find an individual capable of focusing so much as to see the picture of mona lisa in his mind, the "particle" will draw mona lisa on the detecting screen.

[@Nothingness000]

@@promoteamutube Perfect! This is what enlightened sages have said too.

[@cecielisabet1690]

That sense we get when we feel like someone unseen is watching us is the atoms in our bodies doing what they do best.

[@bethbartlett5692]

... that feeling you'll get when you actually realize, "Lots of unseen, NonPhysical, are watching you/us, all the time" - just keep observing Quantum Physics and *"keep mind fully open, free of predetermined beliefs, theories, opinions" i.e. apply the "Standards of Science and Research" ...* ... *"the info will flow to you in relative time".* ... and, *Keep in mind, the "Universal Law of Attraction" is Absolute.* Nothing to fear, it is all very Positive.

[@Nothingness000]

Consciousness watching the body-mind

[@AskRaghulan]

Law of attraction is an example that our consciousness can interfere with the reality we live in. Same way people believe in prayers has some effect to cheat reality.

[@aga1nst]

I remember 20 years ago my elementary physics teacher mentioned this experiment and said "and this is where our physics ends". I didn't remember anything about the physics, just that phrase. Now as an older guy i decided to google it and see what that was and if they figured it out. I'm so glad i did, this has to be the coolest bug in the matrix that I've heard so far :D

[@schmetterling4477]

So you met an idiot with Dunning-Kruger. So what? There are thousands of them in this comment section alone.

[@aga1nst]

​@@schmetterling4477 whoa, what does Dunning-Kruger have to do with what I said? You're high or what?

[@schmetterling4477]

@@aga1nst A physics teacher who says that "this is where our physics ends" is displaying Dunning-Kruger. (S)he doesn't know what (s)he doesn't know.

[@aga1nst]

@@schmetterling4477 you mean she should have said "this is where *our understanding of* physics ends"? That's what she said actually, but it got lost in translation. Really big deal, if you get triggered by things like that, you have issues.

[@schmetterling4477]

@@aga1nst No, she should have said "This is where MY understanding of physics ends.". That she didn't is where her Dunning-Kruger starts. You are not very far away from displaying it, either.

[@Brandezi84]

This is so fascinating! I could learn this stuff all day!

[@steefv781]

What did you learn ?

[@benbarnett9086]

@@steefv781 quantum mechanics

[@inimene3796]

MIT must be a place for you my friend

[@lazurm]

Title misnomer here. It's not about the explanation of the slit experiment but, rather, the depiction of it.

[@Djanoko]

Maybe it's not the particle changing it's behaviour when it senses that it's being observed, but rather the sense of perception of the observer changes as they are observing it. I guess what it's scary a bit about it, is that it implies that reality is probably just an illusion of one kind or another, depending how you're looking at it, as through different looking glasses.

[@mirrorimage5423]

A particle is the finite state of a wave. Infinite possibilities forced to finity, by the finite state called life.

[@Heybuddy101]

mirror image are you kk bruh?

[@nemo17923]

My brain hurts in the best of ways

[@vxctxm211]

Holy shit dude this is bizarre!!! I can't think of a single reason this would happen. That is fucking insane!!!

[@clarin3318]

The detector added a factor. It was just unplugged. We need more detail Information. Im sure someone will figure this out. This is easier to understand than previous once’s I’ve seen. I hope to see another one with what they actually use to “‘detect”

[@FireStorm821]

this doesn't explain much to me at all. what isn't explained here is how the detector works, that seems incredibly important. how are you "gently" observing. how is the detector actually detecting? by shooting photons or some other particles that would collapse the wave? Then its not really an observation so much as an interaction.

[@FireStorm821]

thanks that's what i thought, the "detector" is actually more of a "photon shooter" correct? and its not that "observing something" collapses the wave but shooting light at something does. but if that the case do we know why particles interacting causes this different behaviour?

[@gillywibble]

Don't unplug the detector, leave it plugged in but let the detection results be unviewable. That way, you will know whether conscious observation affects the results.

[@supersonic174]

no you won't know because the results are not known duh

[@bartdog59]

Aweri Blakely you still know where the particles ended up though whether it Is the two points where it would act like a particle or the fringes where it acts like a wave Hes saying don't view the results of the detector across the top slit

[@alienzenx]

bartdog59 They said make the results be *unviewable*. The only way to do this is to unplug the detector. Information cannot be destroyed, only scrambled. Obviously it would violate causality if it were possible to later find out which slit the particle passed through after the interference pattern had already been observed. You could argue that theoretically someone could record the information, but keep it locked away untill the end of the universe so that no conscious observer ever observed it. But since when the universe ends there will be no one to confirm this one way or the other...QED. It could be possible that you leave the recorder on and observe an interference pattern, but you would never know if the recording instrument had worked or not without checking the results.

[@supersonic174]

alienzen if you unplug the detector it might as well not be there, no complicated scenario there

[@alienzenx]

Aweri Blakely yes, so what?

[@Eztoez]

Do not confuse the observer effect with the uncertainty principle. The presence of the detectors is an irrelevance (per Richard Feynman). The double slit experiment shows the wave-particle duality of matter. You can actually perform the experiment at home using dental floss and a laser pointer.

[@aaronodom8946]

Rico G The detectors are irrelevant? Im sure physicists have done this experiment in many different ways trying to find out what causes the wave interference pattern to go away. One thing is for sure: THERE HAS TO BE KNOWLEDGE OF WHAT SLIT EACH PARTICLE WENT THROUGH. It doesnt matter how you find this out, as long as you know. The only way possible is using a detector. After all these years, why would a detector still be an intrical part of the experiment, but not be needed?

[@aaronodom8946]

Michael L Read above? What am I suppose to read?

[@SorinVBogdan]

aaron don't bother, people want to believe it's magic or god or the multiverse doing it. Look at the experiment again. The only variable in the 2 experiments is the detector being on or off. How on earth do people then negate the influence of the detector?

[@DennisMathias]

Well, what if you could plug and unplug the detector (observer) really fast. Statistically what would be the result?

[@Latigo]

The way we explain things makes all the difference. This person gave the best talk on the subject that i've seen so far. Thanks a lot!

[@myeflatley1150]

The experiment will turn out differently if a single-photon light source is used. The current experiment uses a semicoherent light source. The semicoherent light source sends packets of light thru the apparatus, not individual photons. To do the experiment correctly, it must use a light source that truly, verifiable produces individual photons. The double slit experiment has never been done with a single-photon light source. Photons are particles with a vector characteristic. This enables them to be little waves that are spherical in shape. That photons have a vector nature is shown in their ability to polarized in one direction or another, or even circularly polarized so that they are spinning in their direction. Electrons are like that too. Think of the direction as a fourth dimension if you like. I like to think of the photon direction as a vector of electromagnetic intensity and direction assigned to each point in the photons tiny spherical wave.

[@David-bc4rh]

From what I understand, this experiment has been performed elsewhere using single photons.

[@Rynathee]

Photons are not particles.

[@raulepure9840]

It's about information and not consciousness at atomic and subatomic dimension particle are not physical but like probabilities (waves), when you measure them you will transform probabilities in certainty so it will manifest as particle under law of tangible physics It's a world of bits of probabilistic information so when you measure you get certain information Just information can change information

[@skub22do]

why would measuring transform probabilities?

[@oiseaubaladeur]

Thank you! I hate it that people present this as some magical shit, but totally ignore Heisenberg’s Uncertainty Principle...

[@oiseaubaladeur]

skub22do - When you measure the location of a quantum, you know the place/state and therefore prevent it from being in an other location.

[@fabioaraujo8379]

I must say spookiness has never been so elegantly put

[@LocalMotif]

I am 33, and just showed this to my 67-year-old university-educated, bible-following father. At the end of the video, he was speechless with raised eyebrows. My hope is that he will watch more of these with me in the future.

[@kylekitzman]

Dont you think showing your dad things that are beyond his capability to understand is going to make him believe in the Bible even more so

[@lawrence1318]

You'd better think a bit more about your own beliefs. That light is both a wave and a particle mimicks Christian theology: the Trinity is both 3 (which speaks to particles) and yet 1 (which speaks to waves). Commensurately, the bible says that "God is light". So the material world speaks to spiritual realities. God is light and God is 3 and 1 at the same time. This is an exact parallel of what has been shown here about light's behaviour. Couldn't be more exact.

[@IDSForecasting]

​@@lawrence1318 What did Pope Urban VIII do by trying Galileo for heresy? You should look at Proverbs 8:22-36 as the first mention of the Trinity (the LORD, me, and him) and its definition of creation.

[@MsRajfriend]

The electrons exist beyond "time"; firing one at a time has the same effect as firing a set of them--as if each electron is affected by others that are fired before and after itself (without "time" they met in space and created the interference). Adding the monitor, introduces a time event, i.e., each registered pass or unregistered pass, and electrons behaved accordingly.

[@davidgrigg3669]

Yes, maybe the electrons exist beyond time (whatever that is) things don't happen sequentially they just happen, sort of all at once. Could this theory be checked out by some kind of modification of the experiment? Maybe you could (for example) block off one slit, take the screen away so that nothing has been observed in any way, blast some electrons through. Then, close that slit, open the other slit and put the screen back. If you still get the interference pattern, then it would suggest that the electrons do exist beyond time because the electrons are interfering with the ones that were there 'before' (when the other slit was open), but because there's no such thing as time they are both there together. If you don't get the interference then it would suggest that the electrons exist 'within time', but it would be nice to know one way or the other wouldn't it. I think you'll probably find that they do exist within 'time' and the reason for the result is that electrons and the like exist as probabilities until you observe them, but of course everything is made of electrons. So that explains why that tree that fell over in a forest somewhere didn't make a sound when there was no one there. It was because it didn't exist because there was no one there to be aware of it. It's just the way the 'world' works, it's all an illusion. However it seems real enough to us in the 'real' world, so I'm going down the pub!

[@dontsub7150]

Double Slit Experiment NOT explained! by Jim Al-Khalili - should be the title

[@oiseaubaladeur]

Don't Sub - So true! He just told us what the experiment was. I find it so frustrating that they post this kind of video’s. It’s presented in a way you could compare with how sexual intercourse is explained to young kids; telling that it’s just something magical and not explaining it for real. It creates a misunderstanding of quantum mechanics and that’s a shame.

[@Bill-uo6cm]

@@oiseaubaladeur No one can figure out how it works.

[@blvxkgxldimperialllc1677]

EXACTLY

[@jakenguyen2584]

He explained the experiment perfectly fine. The answer to the question raised by the experiment, however, is a different matter. Hence, the title is appropriate. Stop commenting on KZbin, please, thanks, bai.

[@richardverney6702]

@@jakenguyen2584 No. I consider that most people would think that he is detailing the experiment, but he is not explaining the experiment. He is telling you how it is conducted, and what the result is at various stages, but there is no explanation save other than at times atoms behave as particles and at other times as waves, without explaining why that is the case.

[@Husky511]

Call me stupid but surely any equipment with the capacity to measure the position of something as small as a single atom, must have the capacity to interfere with the particles, thus changing their behaviour at some as yet unknown point. The "mere act of observation" is not relative to the experiment - this seems to suggest that somehow just looking at the particles makes them change I don't think this is the case. Build a machine that can detect them from a mile away, hiding behind a hedge - then come back and tell me its still affecting the experiment. Then I shall collect my "Knob" el prize.

[@v3le]

exactly!

[@googelplussucksys5889]

Well, of course the equipment is interfering with the particles and thus the behaviour of the particles change and that's exactly what we're seeing. "Observation" is the scientific word for interaction with.

[@191246mann]

***** seems to me there are a lot of questions to ask,what is the detector they are useing,and what is the patern on, photografic paper?,any way you get this patern if you do the experiment yourself with a light bulb with the patern effect and your looking at everything then.

[@googelplussucksys5889]

chris keeley You can quite basically do it yourself with a laser and polarising sheets towards any surface in your living room.

[@Krish-jm6ve]

The example give here is just for illustration. Check out the actual equipment and how the 'detection' happens. Its weird !. There should be no information in the universe available to know which slit the 'particle' passes through, else the wave function collapses

[@abdullahalmutairi-zr7sn]

Its not an observer , its a detector that's why the electrons change their behavior. The detector is influencing the electron so its wave form get collapsed . What I mean is that a detector has to interact with the electron to take measurements we just call it an “observation” for the ease of language. While the true meaning of observation that we all think of is pure measurements and analysis without interference with the target, which is not the case here with the double slit experiment.

[@Christopher-mx9hd]

So if you quietly turned the camera back on halfway through the experiment, would the atoms start behaving differently? And the same with the lightbulb, would the 6 lines just morph into 2 suddenly?

[@peterhoulihan9766]

The answer is no, they don't. This lecture is nonsense. It's true that you can't detect the particles without affecting them, because they're hitting the detector, but they don't care if there's a conscious observer or not.

[@D4narchy]

@@peterhoulihan9766 This lecture is perfectly correct. Jim Al-Khalili never said anything about a conscious observer. His last example is also a very oversimplified explanation (for the layman audience obviously) of the quantum eraser experiment.

[@peterhoulihan9766]

@@D4narchy It sounds a LOT like he's talking about human observation affecting the experiment. If that's due to the simplification then he simplified it too much.

[@larkian6919]

@@peterhoulihan9766 - You think they are hitting the detector? If that’s the case wouldn’t it produce a completely different result depending on where you place the detector? The particles/waves would be pushed in different directions based on the detector placement. How does the detector transform the resulting pattern from a wave pattern to a two line pattern just from placement in one spot? You would think you would still get a wave pattern with some interference for particles/waves interfered with by hitting the detector. This would change if the detector was to the left, to the right, etc. I don’t have a answer but I doubt it is something as simple as you are stating. This scientific mystery has been around for a while now and has been studied by some very smart scientists. If they have not been able to solve it, I doubt that there is a simple answer.

[@peterhoulihan9766]

@@larkian6919 "How does the detector transform the resulting pattern from a wave pattern to a two line pattern just from placement in one spot?" It doesn't. The result is the same whether a human is watching or not, or what kind of detector is used. The "observer effect" comes from the fact that you can't detect particles without affecting their trajectory. It doesn't alter how they pass through the slits.

[@tcharleston81]

I'm no QM expert, nor do I know the details of the experiment, but the conclusion that our consciousness affects the behavior seems like a bit of a stretch. I find it more plausible that the behavior changed when we added a variable but we don't yet understand why.

[@SorinVBogdan]

Exactly. But the only variable is the detector being on or off. So therefore logic would dictate that the detector, or the method of detecting, is interfering with the experiment.

[@Innovadsign]

ooh you sweet summer child

[@lance249]

what about the delayed choice quantum eraser experiment? In that experiment they entangled the particles after passing through the slit. They sent the particles on different paths with different lengths. The first particle hits the detector and THEN moments later second entangled particle is then used to determine which slit the particle went through. They found that even doing this measurement this way, it would collapse the waveform and you would be left with just the two stripes and not the interference pattern. If however you don't measure the 2nd entangled particle then the first one would continue to create an interference pattern.This not only shows its not the interaction with the particle physically that it causing the collapse, it also shows that by measuring the 2nd particle you are effectively rewriting time somehow and forcing the particle that has already hit the detector wall to be create a wave or a strip pattern.

[@Mr.Honest247]

Theresa Charleston Nope your responsible for everything that happened to you through the law of attraction. Science is finally catching up to explain the spirituals truth.

[@hansvonstetten3236]

this is the only conclusion that makes sense in a sane world...

[@terrysouth7201]

for the double slit experiment, the fluorescent screen is essentially a 1D measuring device, and that's why we only see the 'point' of the particle as it passes into/through the screen. What if you made that 'screen' a 3D box or trap...maybe like a cloud chamber, but something more permanent - that could literally show/record the path of the wave/particle as it passes through it? then you should see the full wave like behavior of the photon or whatever as it passes through.

[@AsterothPrime]

yeah, like ballistics gel they use to test the travel of bullets? would be able to see how the particles end up where there do.

[@Tsharkeye]

Watch the video by "looking glass universe" to see the waves even before they hit the screen (through a smoke machine)

[@WalterSamuels]

Exactly. It's hilarious that all of quantum mechanics is founded on this nonsense when they couldn't even think of a good experiment that would validate it. Instead they just ran with it and treat it as gospel. Physicists are really lacking common sense.

[@DR-mq1vn]

This blows my mind! And the man explaining it is no nonchalant about it too. The atoms are aware! This is so freaky!

[@karlkarlsson9126]

They aren't really aware, as we know of, sorry to say, it's just a figure of speak to try to explain.

[@91JLovesDisney]

​@@karlkarlsson9126Yeah. But they definitely have properties that make it feel like they know things. I am no qm expert, and I've been reading your comments and it seems like you are. So here's my theory I don't think this is an original theory, something I learned from vsauce probably, but I think that all quantum particles have pure randomness programmed in. Where they will land on that sheet is determined purely by chance, there's simply a higher mathematical chance they will land in specific areas, creating the interference pattern. The fact that the interference pattern looks like a light wave interference pattern could be relevant, or could be a coincidence. I truly don't know what I'm even talking about, just talking. This has been stressing me out all day

[@karlkarlsson9126]

@@91JLovesDisney I'm no expert either :), but I know enough about this experiment by now that I want to help people who struggle with it, because even if videos like this are great, they often ends without any Q&A. What you say is somewhat what the experiments and the current math says, no one knows what a quantum wave is physically, but the math and the experiments suggests that it governs the probability of the locations of the particles based on a wave like nature, which explains the interference, similar to when two water waves interfere, and you can use Schrödinger's equation to calculate the probability. Some physicists calls it "potential particles", meaning that they don't really exist prior to observation, but the potential locations for them exists until they are being observed, which then determines the one location govern by the "probability wave". This is the part that makes it seem that particles are aware, but as it suggests it's not that it's particles are being aware, as you say about particles having randomness programmed into them, it seems that before any observation is taking place there's already an existing wave of probability as to where a particle will show up (superposition), and we can't get a good look at that situation without changing it by trying to observe it. So it seems that it's rather the observers when becoming aware of the fact, or the receiving of information that changes the outcome, which leads to interpretations of consciousness being fundamental, mind creating reality, but this is another controversial interpretation among many.

[@91JLovesDisney]

@@karlkarlsson9126 Right. Okay, I gotcha. That is kind of what I've heard, but it's so hard to wrap my brain around (obviously) It feels like humans weren't meant to go this far

[@karlkarlsson9126]

@@91JLovesDisney I agree, it does feel like that sometimes, from the vast and big distances in space that we can not cross, to the very small that we can't see or grasp. Do someone wants to limit us?

[@zioo3117]

Perhaps the sensor (unless hidden effectively) somehow stimulates the condition of magnetism; electro-magnetism; or gravity, which creates the opposite of the Space/Time Duality. Or this sensing changes the wave particle duality via anti-gravity. Further, this may have something to do with dark energy at work or the magnetism of dark matter. Just some random thoughts on the double slit experiment.

[@shazanali692]

What you have said is impossible, all tested