Quantum Entanglement and the Great Bohr-Einstein Debate | Space Time | PBS Digital Studios

For those of you in New York City you can check out Matt live at PBS Nerd Night at the NYC KZbin Space on Thursday night September 22nd. Hope to see you there. to.pbs.org/nerdnight
Albert Einstein strongly disagreed with Niels Bohr when it came to Bohr’s interpretation of quantum mechanics. Quantum entanglement settled the argument once and for all.
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Previous Episode - Self-Replicating Robots and Galactic Domination
• Self-Replicating Robot...
Veritasium’s video Quantum Entanglement and Spooky Action at a Distance at 7:36
• Quantum Entanglement &...
How the Quantum Eraser Rewrites the Past at 8:41
• How the Quantum Eraser...
Einstein argued that elementary particles maintained their intrinsic values whether they were being observed or not. Bohr believed that in observing such particles we collapsed a wave function of probabilities. He asserted that it is only when these wave functions collapse that one of many probabilities is chosen and the particles take on distinct values. Quantum entanglement, John Stewart Bell and Alain Aspect eventually proved that Bohr was correct.
Written and hosted by Matt O’Dowd
Produced by Rusty Ward
Made by Kornhaber Brown (www.kornhaberbrown.com)
Comments:
Borne Stellar
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[@arkatub]

This comment doesn't exist until you read it...

[@teemusid]

Did I exist before I replied?

[@rynstrs]

Not to us you didn't. P.s. Please slow down with the wave collapsing, there's only so many to go around.

[@Tom-fh3zg]

I have to pee and its gonna be a wave........ I have to tell you it feels like reality

[@Rhekon]

You definitely exist in an undetermined location by my perspective.

[@jimbones1916]

Observing this comment has altered its original meaning.

[@YourBeingParanoid]

The universe was created at my birth, it will vanish at the moment of my death - be warned.

[@omegasrevenge]

All is relative. It may vanish from your perspective, but from mine it will stay perfectly fine.

[@YourBeingParanoid]

abschussrampe no it won't - but I'm willing to allow you to prove it to me somehow

[@akrybion]

The fact that I know for sure I exist know, without you interacting with me tells me The universe in truth is enturely dependent on me. Thus I conclude I should be able to temper with it's rules, know be still mortals while I reconfiger space and bring back Firefly

[@acio83]

It has already vanished a few times while you played peekaboo as a baby, so we are not afraid!

[@YourBeingParanoid]

akrybion don't tell fibs

[@roberthofmann8403]

I spoken with many people that interpret this as, "nothing is there until we observe it." I always counter with, "Everything, all possibilities, is there until we observe it."

[@wesjohnson6833]

From an informational point of view, they are both the same.

[@monkerud2108]

@@wesjohnson6833 no silly goose, unless you discount realism, you might as well invoke magic. its the same from an informational point of view for YOU, not for the universe.

[@fuckoffgoogle8199]

Sounds like a religious debate.

[@blvxkgxldimperialllc1677]

Possibly the Glass is half empty and/or half full..

[@cmdr.shepard]

You only interpret one interpretation. Copenhagen. Many Worlds Interpretation on the other hand, which can be argued to be the only true quantum mechanics interpretation, because it doesn't introduce additional elements such as a supposed "collapse", says everything is there before and after observation!

[@wishiwsthr]

This stuff is way over my head, but I can't stop watching.

[@DreamZzZz999]

Dude fucking 100% same

[@brokentombot]

Exactly. Half the time I'm confused or in denial but I still just keep watching and even re-watching some to the same effect.

[@thoughtsfromahead]

Haha, keep going! Maybe someday you will derive meaning from it.

[@miketuroczy695]

Keep watching these and other videos.... you will start to understand some of it. Until the math comes in.... if you're like me it all falls to WTF then.

[@P-G-77]

I think exactly the same...

[@slpk]

Man... credits to the graphics team behind these videos. They are always SO GOOD!

[@jaik3n]

thanks :)

[@nesobre]

yeah i agree tiz crazy

[@victortrying]

Don't forget about the soundtrack, which is awesome right now on my headphones

[@_N_O_X_O_N_]

What software are they using?

[@graysonblackmon4409]

After Effects and Cinema 4D, primarily.

[@fahadus]

"Peeka-boo Universe" "The Big Bang" "Spooky action at a distance" The thing with making fun of your fellow scientist's theory by giving them condescending names is, that if they're right, all these terms would be embedded in scientific literature forever.

[@reigh7]

I've been reading a lot of the comments on this because I got a notification. While it is fun to poke around at the possible mechanisms at work for entanglement as I often try in my mid to imagine the intricate worlds of I think with things like this and the location you may detect an electron at is that it's a filed of probabilities and probably moving so ie both states, or connected states however it is set we can observe and fine statistical patterns that can be used to test and repeat and see other patterns that points to the statistical idea of not knowing for instance one of two spin states before you measure but that and the cat is an example as these states are not alive and dead but equally opposite while being able to change from one to the other without us seeing but we know that with a certain degree of precision with things like this or more likely places to find an electron certain other relevant information we can test for like the other entangled particles spin orientation being opposite although with that one since reading it takes a system of gates that can sometimes throw error into the system but with a high degree of repeatability it does show correlation at a distance with no discovered wave communicating the information and if either's is disturbed (ie observed) then they stop being entangled. There is a method to this statistically useful information allowing us to build working and ever better quantum computers right now that do annealing for finding lowest states of energy in calculations of efficiency that fully function as expected based on some of these principles. Other things like extra energy from heat have to be removed so as to disturb fewer of these states in a system and so on. I'm no expert it's just fascinating how to tackle the concepts we have in our minds.

[@earthspeakers]

Peek a Boo 😂

[@FR-yr2lo]

“The observed quantum spin aligns itself with our chosen measurement.” Vertically or horizontally. If the axis we choose determines the orientation of the entangled particles’ spins, cannot quantum entanglement be used to send information instantaneously, at a distance?

[@michaelbishop5913]

this stuff simple family is it not kick back eat some pop corn this like 2+2

[@rishitgome2073]

@@FR-yr2lo but for example you take one particle in our galaxy and measure it so the other particles wave function collapses but in andromeda galaxy you have to measure the particle to know if it's wave function collapsed Or not which will automatically collapse the wave function even if no one really sent a signal from milky Way it can be misunderstood as a signal, and particle spins are very random if we force it to be one of the spins it will break the entanglement so you really can't send the signals

[@bormisha]

Man, the quality of your materials is vastly superior to most other scientific-popular videos I've ever seen on the net. Big thanks for making!

[@massiveeyebrows4482]

Ah so this is what Jada was talking about!

[@pluggak321]

Looking for this comment🤣

[@netteleverett4871]

Hilarious!!!🤣🤣🤣☄️☄️☄️

[@ChrisProuse]

Words can't fully describe how good this channel is - it's out of this world :)

[@yaminoroy]

and out of this time

[@ChrisProuse]

Roy Malamud Haha, so true 😊

[@jojojorisjhjosef]

ikr

[@luongmaihunggia]

+Roy Malamud lol

[@jaysoucy1309]

This channel revives me after a long drawn boring meeting about business.....

[@jimmytwotime3318]

"There is no spoon."

[@metruna]

@Binguh Bungah amem

[@ynntari2775]

There are all spoons

[@alkestos]

There you only find out if you open the box.

[@Bassotronics]

Quantum Entanglement in a nutshell. Particles see each other and fall in love. If you separate them, no matter how far the distance, their love for each other will always sustain. If you change the value of one, the other will change too due to quantum love chromodynamics.

[@Stanwich2781]

But if you cheat on your partner they don't find out instantaneously.

[@yezambiquerahma259]

How can you change the value?

[@Bassotronics]

@@yezambiquerahma259 With a kiss.

[@BJoinedBReality]

Lewis Carroll was deeper than most people thought: the Chestershire Cat lacks Object Permanence.

[@aaroncurtis8545]

Well, that's because the guy that wrote it also invented a lot of the math we use to do multi dimensional geometry. The Alice books are a treatise on hyper diemensional logic. Like... Really.

[@P-G-77]

poor cat... :)

[@japhetzayas7194]

True. It appears that Carroll used literary art to express intuitively what physicists express mathematically and scientifically. This convergence of science and myth is found in Far Eastern philosophies (the dance of Shiva), and the metaphysics of Schopenhauer. The book, "The Annotated Alice in Wonderland" is an interesting examination of the esoteric nature of science and metaphysics.

[@loturzelrestaurant]

@@japhetzayas7194 Japhet? Can i recommend you some science-channel on yt?

[@eunoia6184]

@@loturzelrestaurant yes please

[@amz2424]

Matt was my astronomy professor in Lehman College. Best professor ever!

[@ThomasJr]

wow, he sounds amazing. I wonder if he's as smart as he looks here, or if it's just him reciting pre-existing texts written for him.

[@VocalTK]

@@ThomasJr I've seen in at least some of the video descriptions that he's the one writing at least some of these.

[@rbettsx]

That is quite simply the most clearly written, compact, and precise English-language description of entanglement I have ever heard. Congratulations.

[@OnideusMadHatter]

Here, I'll give you an even simpler one that isn't absolutely retarded... Take two spinning tops from ONE starting location (you) and spin both tops away from one another with reflective angles, momentum, speed, etc, etc. Presuming the surface is completely flat/identical (effectively a vacuum) both tops will be spinning identically to one another (although inverted/reflective). When one top stops spinning the other top will also stop spinning and they will appear as if they are the SAME spinning top, reflected across the distance that that they were spun away from one another. It isn't that one top is in any way ~influencing~ the other top, it is simply that both tops were essentially programmed with the same function. You can take a copy of Microsoft Word and you can boot it up on any computer on the planet and get the exact same functionality... not because the software is in any way linked, but because the software is IDENTICAL. When two wave particles collide they spin around each other briefly until they reach a uniformed/reflective spin caused by their pole arrangements (positive and negative) directly crossing one another, so when the positive pole of one wave particle aligns directly with the positive pole of another wave particle they act like magnets, breaking away from one another and as their poles are directly aligned when they break away, assuming they're in a vacuum with nothing else to interfere, they will wind up with the exactly same spin (but inverted/reflective). So... no... sorry, it's nothing magical at all... code a program, copy it across as many computers as you like, as far away from each one as you like and each copy will work exactly the same. ...it's funny, because it's exactly like peek-a-boo... except for adults... like you actually think it's some magical thing but only because you don't understand the exceptional simplicity of it all. :D

[@jordanfaydherbe7394]

Mmm. Sorry but the analogy you are using doesn't exactly match up with the description of entanglement. I suggest watching the video again and doing more research, try not to rush too quickly to find an answer to things or think you know what is going on.

[@OnideusMadHatter]

I've watched a LOT of videos and read a LOT of stuff on the subject. When I first looked into it, it seemed to be a simple matter of not understanding the observer effect. Simplest explanation is checking the air pressure in your tires... you cannot check the air pressure without letting out some of the air in the tire. Cause... and effect. You cannot perform an experiment without having some impact on the outcome (for any number of potential reasons). Any action you take to try and "observe" something will have an effect. Electrons currently cannot be detected/measured until we hit them with photons, but in doing so we cause a change in the behavior of the electrons. In other words the means of measurement has a "cause/effect" relationship with what's being measured. Think of it like shooting a ping pong ball across the surface of a lake... the lake being like photons. In doing so the particle, the ping pong ball, can have BOTH the properties of a particle AND a wave simultaneously. But, like I said, that was just my first take. There's MORE to it, which has to deal with spin alignments caused by magnetic coupling and separation. Ideally I'd like to do some experiments in zero gravity, basically take some ping pong balls with magnets inside and then randomly toss them towards one another and see how they interact.

[@Cscottprice]

Personally, I think it would be better to quit talking of entangled particles and instead give up on the idea that there are 2 particles- at all -meaning that perhaps in certain cases, the 2 particles are not 2 particles at all and are instead a split wave function where the "entity" is not 2 particles at all but is actually ONE "thing" that has two pieces separated in space until a measurement when they are then split. Since the object is ONE thing ,not two (**ie there is NO pair) , it gets us away from the verbage about entangled as well as the language about communication between them --since there are not two things at all)

[@ricardomianelli]

I'm currently doing quantum mechanics at masters program of physics teaching and that is the best explanation found on youtube so far. Keep doing that great job, man! At first you had my attention, now you have my admiration.

[@keyton1928]

Ricardo M. Ianelli I’m always fascinated by new stuff, and I am about 20 minutes new to this topic. So does quantum entanglement form naturally, or only when we force it (if I was interpreting it right)?

[@billhannahkuhn6463]

As a retired engineer who worked decades with scientists, I find the topic utterly fascinating yet beyond my reach (too old to become a capable physicist). Thank you Matt and everyone who created this--it's the best explanation of entanglement I've heard. Clearly I need to spend more time with this channel. --Bill Kuhn

[@ericephemetherson3964]

It is never too old to become anything you want. I am also at the age of what you called '(un-capable). But I still study physics and am writing a book on my experiences with physics in school and outside of it. Don't give up. Here is my thought on the video. There is a misconception about quantum entanglement which I've been familiar with for decades. Quantum entanglemen involves two patricles (electron or photon) that have interacted briefly. The spooky action at a distance is produced only, and I stress here the word ONLY if these two particles interact. No other situation will allow for EPR experiment to ensue. But I say; what is the state of wave function of two particles that had never interacted? The Universe is made of particles. So, what about some two random particles just floating in the Universe and suddenly they wanted to communicate with each other? From the prepositions of entanglement there has to be a predicate for a reqirement of particles interact. Let's say that there is no such thing as entanglement so no information nor communication is avaliable between such two entities. The Universe would be in chaos. I believe in non-locatity and all parts of the Universe must be in constant communication with its own parts. Another thing I have never heard phycisists do: why don't they entangle three particles by briefly letting three electrons interact with each other? What would happen then? Also, the nothingness is a part of object permanence.

[@daverumpel]

I love the new sound it makes when you like a comment.

[@ZyNeEnZyNe]

Same with the dislike! :)

[@DMsubble]

WOW i wish this wasnt 2016 and i hadnt seen that comment 5 years ago

[@SG99_]

says the guy named roflcopter with a old meme as a profile pic

[@DMsubble]

sunjot grewal the fuck? wouldnt that just prove that i saw it that long ago? you inbred fuck

[@SG99_]

r0flc0pterl0l talking about annoying dated memes when ur made of dated memes is hypocritical

[@vp9041]

watching this makes me feels like, we are in a simulator and humans are trying to decode it

[@hazel6221]

@Binguh Bungah Woah crazy over here

[@nicknyk7174]

@@hazel6221 Not crazy, just ignorant and cheated.

[@devidodge]

@Binguh Bungah clearly you're delusional

[@tensevo]

How would you know whether or not you were in an advanced simulator? How could you prove either way?

[@Drew8]

@@tensevo That is a very unique question, a digital agent and existing scene are detectable by a device that already contains algorithm keys that can access an actual copy of the digital agent and pick up background scenes, where it can input a record of the time and event the digital agent exist to allow the digital agent to access a copy of themselves. The device that can input the digital agent detects their programmed energy as active, and it stores a new algorithm key through each copy in a memory software machine bank. The only device within humanity that can verify a digital agent through a digital screen is a camera. The technological design of a camera shows that the actual person who created the device knows they're a digital agent, and they know how there's a biosoftware machine that can simulate programmed energy very fluidly to build up existence.

[@XuryFromCanada]

it's my favorite video on the channel! But... I have to admit.. I play it when I can't sleep. I fall asleep 100% of the time before it's finished.

[@erickalvarenga]

Love you been searching for the past year where entangled particles come from. You have no idea how good this is

[@sebmata135]

I wonder if we will ever create an experiment that will definitively prove or disprove realism or locality. Also I'm really looking forward to the episode on the Many Worlds interpretations and an episode on the underlying nature of causal interactions!

[@pwkn86]

ditto!!

[@garethdean6382]

Well locality has been disproven definitively, it's just realism that's up for grabs now.

[@sebmata135]

No, Matt said at the very end that locality and realism can be preserved with the Many Worlds interpretation. Also I'm supposing that if entangled particles are connected by wormholes then locality would be preserved since no signal would travel at faster than the speed of light between the particles.

[@metatron5199]

Classical locality would not be preserved if they were connected by wormholes. This is exactly what bell was speculating when he said bohm has put on the right path.... Particle entanglement via wormhole is not considered to be local. Aspects experiments proved that bells inequality to be false showing that the universe is in fact non local, remember locality comes out of classical mechanics and more specifically our modern notions of locality is derived from General relativity. If your interested in this subject matter you should look into all the physicist doing work under the banner name of " a quantum theory without observers". As far as many worlds there is no evidence to support such a claim and why you now see many quantum computing physicists turning the corner and leaning towards bohms interpretations of quantum mechanics. The many worlds interpretations must invoke ontological principals (such as an infinity of universes) which we have no way of showing evidence for such a claim currently. By most philosophers/physicists standards/accounts the many worlds is not a realistic account of reality as per the major caveat I have mentioned above and is why many QC experts have abandoned the MWI, it just does not make any sense with current observations. As I said this can all change but there seems to be good reason to be sympathetic with Bell in that we should see that bohm in fact has shown us a way, obviously not the way, but certainly a start to a better interpretations.

[@javierdiaz-s3702]

I always wondered if the quantum world weird behavior could explained by having an additional time dimension at least at that scale 🤔

[@victoraguirre7486]

What's up with the late upload PBS??? STOP PLAYIN' WITH MA FEELINGS

[@enginear4973]

No, it's not late, it's just on time in my refernce frame.

[@victoraguirre7486]

But if this is youe current reference frame, then last week's was early for you?

[@akhilp3559]

lmao this guy^^^

[@thomasscott116]

As a teacher 👨‍🏫 I really appreciate this channel. It is good for me with a PhD and great 👍🏽 for students. Sometimes I have them watch your videos then have them write down something that they learned, interesting to them, or pertinent questions about the video. Keep up the great work!

[@slightlyannoyedotter]

7:55 this man just got this year's physics noble price for his contributions to the quantum sciences! What a wild coincidence.

[@tangytanger1ne]

Noble price lol

[@dhu192]

Reality Continues To Ruin My Life. I hope that babies can solve it for me.

[@Rhekon]

Something something childish actions something something child's play

[@UpcycleElectronics]

Babies have ruined my life. Somebody bring me back to reality!

[@ttrev007]

Babies don't solve problems they make them.

[@RtGFuSiOn]

Maybe this is the matrix's way of minimising resource use. When no one is observing an object or space, it no longer exists. I can only assume that it was not intended for us to discover this 'new' reality. We're all going to get reset if the physicists don't stop their research!!

[@oonmm]

+ttrev007 And adults makes babies...

[@guthoriantony]

this is probably the best video you've made!

[@johngrey5806]

No, I like the one with the wild eyebrows better.

[@garethdean6382]

Many people think this remains the best video he's ever made, even when you're not watching it. However experiments with comment sections have shown that we must abandon the idea of a universal best. Instead it may be that every viewer has a different favorite video based on 'hidden viewer preferences'.

[@Prince_Oli]

Lol

[@Sam_on_YouTube]

I disagree. I think this video tries to do too much. Putting entanglement, EPR, Bell, and interpretation of those implications all in one video makes it impossible to properly explain it to those who don't already know these topics and also leaves insufficient time to add to the level of understanding for those who do know this stuff already. I'm hoping this is just an introduction to those topics because it is not up to the level of explanation you usually get in this channel. I'm used to learning something new even in topics I know well. That wasn't the case here. He just tried to do too much in a single video in my opinion.

[@johngrey5806]

Sam, who says it has to be explained in one video? There could be a whole series of videos on these topics.

[@kunalbhagawati9136]

This is the first PBS space time video I fully understood. It may be because I've been watching a lot of other videos and reading about it, or it may be because this video is less mathy, but for the first time, I understand. Thanks guys, this was a good spend of time today! :)

[@JimGobetz]

I don't know why but I am happy that he refers to a "Prime Directive Obeying Civilisation" as if everyone will understand. Such a Legacy Mr Roddenberry has.

[@Cernunn0s90]

Quantum mechanics makes me feel like we live in a computer simulation. The way the universe seems to deny FTL communication, with almost strange/spooky "locks", almost makes it look like some sort of encryption.

[@garethdean6382]

But why encrypt a simulation? Why not just have everything nice and simple? Certainly we don't encrypt our simulations, only things like messages we send to each other.

[@robing4910]

Because we need to have the illusion of free will

[@TehDMBfan]

who's to say the simulation doesn't have bugs and therefore failsafes are needed?

[@jgrove1246]

You might be thinking with the wrong mindset. Looking at the universe around us as a human we find patterns. Is this good or bad? In some cases yes and in some no. But ultimately our knowledge is so nearsighted that we can not tell.

[@chadsmith2281]

That's what I was thinking this quantum entanglement and quantum mechanics leans towards us being in a simulation! CRAZY!

[@charoleawood]

It seems bizarre that Mr. "Time is relative" would have been such a stickler about location....

[@beri4138]

@Binguh Bungah What?

[@beri4138]

@Binguh Bungah Bruh wtf are you talking about. And did you call Bohr a... Greek? You're legit speaking gibberish at this point.

[@forkevbot]

Einstein's relativity still preserved locality and causality, but the copenhagen interpretation of quantum mechanics treads dangerously close to not preserving them given quantum entanglement. But it is as the video says, information is not transmitted faster than light in entanglement.

[@benjaminfeddersen7937]

I like the versions of explanation that just tweak the definition of "local". Entangled particles are adjacent in spacetime by definition. Any interaction with any other particles (such as a detector) severs that locality and creates new space "between" the two particles. Would explain where all this extra space is coming from, as well.

[@PwrTrumper]

really great video! things that can add to this: how can we entangle particles and what are all the particles that can or can not be entangled? how is the measurement of spin taken?

[@david21686]

You forgot to mention another way around Bell's Theorem: assuming that the human experimenter does not have the free will to choose a measurement axis independently from the quantum axis. Superdeterminism is the idea that there are local hidden variables, but the universe conspires to force mankind to perform measurements that won't find them. It has yet to be experimentally ruled out.

[@garethdean6382]

Can it ever be experimentally ruled out? Besides which we always implicitly assume the freedom of the experimenter. This fundamental assumption is essential to doing science. If this were not true, then, I suggest, it would make no sense at all to ask nature questions in an experiment, since then nature could determine what our questions are, and that could 'guide' our questions such that we arrive at a false picture of nature.

[@aaroncurtis8545]

Nice one... That's even funnier than pilot waves :p

[@galenseilis5971]

Testing Superdeterminism directly sounds substantially more difficult than testing models that feature Superdeterminism. I agree with you that the topic of Superdeterminism has not been adequately explored. The "Science would be impossible" complaint is a red herring.

[@n4thanfv]

thank you a lot for another one of these. the text was excellent, the knowledge was easy to understand and see the beauty behind such science.

[@johngrey5806]

You look more magenta than pink.

[@User-jr7vf]

more x ray than magenta

[@kendomyers]

more human than a human

[@User-jr7vf]

lol

[@hudeyfaabdi610]

lol

[@lucidscience925]

Cannot thank you enough for the valuable information on your channel. Awesome, awesome unparalleled stuff.

[@MoisesZTech]

After years of watching this and other quantum/multiverse videos, I finally understand my salvia trip and the quilt world within quilt world.

[@theashennamedjerry3203]

56 seconds in 300 views. This urge to learn gets my hopes up for humanity. Motherfuckers in my class get there 30 mins late and the their exuses is that science is useless because they want to be tv stars. Less compitition for us in the sience fields I guess...

[@mrmonos2631]

people are just retarded science is the way to go

[@MusiCaninesTheMusicalDogs]

Oh, well... Wanna lose your hope in humanity? Check out the size of the audience of religion and superstition videos.

[@joeface123123]

this comment makes me fell bad for being 30 min late to this video

[@fartzinwind]

You can counter that by looking at the subscribers to The bible Reloaded, Armored Skeptic, and others. Though I don't count Amazing Atheist, because he's kind of a dick.

[@fartzinwind]

what's more depressing than watching kids not pay attention in school is watching adults who didn't pay attention in school think there isn't anything more to learn in the world, or think that nothing they learned has been updated.

[@gewamser]

Best show on KZbin!

[@Scribe13013]

The great bohr-einstein debate Sums up this channel pretty well

[@Pkexim]

To explain the Mysteries of the unfathomable universe in a simple and graphic pictorial method for those who have a little aptitude is in itself challenging ,a positive initiative of PBS space time..

[@yodawg517]

man i have no fucking clue what this guy is talking about

[@revatronprime4120]

Try watching the other quantum videos from this channel. Itll help alot.

[@subh1]

Lament! 'Cause you are missing out a lot on the extraordinary experience of being a member of a technologically and scientifically advanced species.

[@Rhekon]

I know enough to keep up most of the time with the basis of stuff like quantum entanglement, but I have to focus a lot when he's mathing for various reasons. My brain generally awes at the math and avoids the Algebra.

[@revatronprime4120]

ZeanutJam Cool

[@pernaboys]

me too..... I get what he says but I feel stupid because I'm just an observer not someone who understand these stuff on his own and even though I have a hard time understanding it. quantum mechanics doesn't make sense and that's the problem with it and its beauty, the world is not obligated to make sense for us, it is what it is and probably only we humans see it this way...

[@NikesDarkslayer]

Maybe the universe stops processing stuff for optimization purpose like my video games don't render stuffs when I'm not looking at (Area Occlusion)

[@tensevo]

You are talking about the Universe as something that is independent from the observer.

[@deathbydeviceable]

That's dumb. If you stop looking at your device while watching a video the sound should theoretically stop. Everything is in existence cause of the wave form. Just cause you don't see the object (like Einstein's moon theory), doesn't mean you don't feel the effects the moon causes. See?

[@tensevo]

@@deathbydeviceable To "see" in quantum physics, is to "observe" which is to say, consciously observe meaning that cause-effect relationships are preserved. So regarding the double-slit experiment, we observe, or measure which slit the particle goes through and it resolves to a precise location, whereas when we do not observe, the particles acts like a wave of possibilities. Regarding the Universe, area occlusion hypothesis, it is not such a bad an idea, but I would remind the reader that this is all theoretical, so even if Quantum physics did ever prove that the Universe was a holographic projection or simulation, we should not confuse the map with the territory. If anything, it is our brains that simulate the Universe for us, it would make sense (from a survival and replication perspective) that our brains only process information that is causally of relevance to us (stuff that impacts our lives). It is not to say, the moon is not there when we are not looking, more that our brain stops processing the moon's existence, when it's effects cease to causally affect our lives.

[@deathbydeviceable]

@@tensevo the gravitational force is still there exerting it's force, just like the sun's and other planets. Sure the aspect of not looking at something the light isn't being processed to the eye, but it's still there making it's rounds to the brain, as you see the light bouncing off the object you're looking at (let's say wall) from the light source (moon, sun,) Sure you can fit that kind of mentality to your life to help you have a better life. If it's not in view it doesn't exist, but like all news, it eventually makes it's rounds. Since when did science become philosophical? Science is an understanding of all, not what you perceive reality to be. Science judges religion as easy answers, and what is science doing now? Easy answers cause no one has a clue outside philosophy. No one wants to look at all angles cause it "doesn't exist". Fuck that, that cat in in one state, and that tree fell hard when no one was around. Why? Cause common sense tells me. We can see the aftermath. How's that for philosophy.

[@tensevo]

@@deathbydeviceable The frontier of Science has always been philosophical with many interpretations of possible realities offered up, before one emerges as the dominant view. Right now there are many different interpretations of Quantum mechanics, it is not settled or understood by a long way. Sure gravity is still there as an assumed constant, but then at one point we used to say the same about time, we assumed time was constant, now time is interchangeable with space. At one point Science said the Sun was the centre of the Universe. What do we think we know for sure today that will be mocked 500 years from now? LoL if you think you can use common sense to understand the Universe and quantum physics then, well, good luck with that.

[@ALtheDoctorWho]

What I find interesting is how we can see parallels in physics. Energy having an effect with other energies

[@pointyfox]

Question: If measuring a particle aligns its axis to the measurement device, how do we know the other particle has a particular axis without measuring the first one and changing it?

[@aviroe1]

If you flip the axis of the paired particle the parent particle also flips the axis even though an initial observation indicated a different axis alignment. It was verified through multiple observations. You can also measure it at angles like 45 degrees that would preserve orientation I believe. Please correct me if I'm wrong.

[@tenaciouscoder138]

No you didn't miss something, they completely left that out. He did however mention another video, which is the best explanation I've seen, Here it is kzbin.info/www/bejne/kKbZfGClmZtnbcU And for a mind-boggling demonstration using polarizing filters (which you could presumably repeat yourself) see kzbin.info/www/bejne/kKbZfGClmZtnbcU

[@yashwanthd1998]

@@aviroe1 there is no inital observation i guess..he didn't the complete the explanation what happens to the other particle damn

[@johnroof5999]

I spent 10 years at Fermi National Accelerator Laboratory where we discovered discovered the "Top Quark" in 19996. I find this lecture informative and straight forward.

[@fahadus]

I'm glad we made it to 19996. Why did you have to come back? What are you hiding?

[@G-doubleU]

I'm not currently studying physics, my level of knowledge is only that of an enthusiast. I just want to say I thoroughly enjoy your videos. Thank you for posting them. Never subscribed faster in my life.

[@schrodingersdad6077]

Same here bro. But if you devote some time to studying up some basics with the vast amounts of videos available on KZbin, then the PBS Spacetime videos STARTS to make sense. That feeling is really cool tho, ngl. I highly recommend the DAILY EQUATION videos by Dr Brian Greene

[@G-doubleU]

@@schrodingersdad6077 Believe it or not, but 3 years on from that original comment and I am now a physics undergrad (first year completed). Thanks for the Dr. Briane Greene recommendation though. I will be sure to check it out.

[@schrodingersdad6077]

@@G-doubleU Wow that's awesome dude. I'm currently doing medicine, wish I found my love for Physics a few years earlier. But I was never really good at any Math lol.

[@Quantum_Arts_Notes]

這是我最喜愛的科普頻道，感謝頻道主製作了一系列優質的科普影片。

[@Quantum_Arts_Notes]

當然是真的，PBS Space Time是最棒的。

[@patrickhawthorneLS]

This is the only proper explanation on KZbin Thank you

[@raidrimouche7312]

so some particles choose properties when some other bunch of particles observes them? Good job Bohr you broke both physics and philosophy

[@gerooq]

@@Anon-uv9mj im no scientist but i doubt particles choose a state after only being observed

[@ynntari2775]

what I understood from Veritasium's video (not the one mentioned in this one, I believe) is that: the particles don't choose properties when they are observed, all scenarios keep existing, in each scenario the particle has a property. What happens during the observation is that the observer entangles himself with one of those scenarios, thus only seeing one of the properties. Actually, the observer splits in many different observers, one in each "timeline", each version of the observer gets entangled with a scenario and interacts with only that scenario.

[@oliverf.4235]

Yes but that is only one of the possible interpretations.

[@warrenbuckley3267]

Had to come back and re-watch this after the Chinese teleportation experiment using entanglement.

[@user-xy7tj8yx1u]

اني me

[@Anna_Fortunka]

If the actual teleportation using entanglement can take place, doesn't that violate causality?

[@mathematicalninja2756]

it does violate it

[@niks660097]

@@mathematicalninja2756 no it doesn't, you can't use entanglement dynamically, the teleported particles are pre-made its like your clones, ready to take your place when you're destroyed..

[@nigelgriffiths5747]

I'd say all your videos are very good please keep making them

[@Sodomantis]

13:49 This quote actually made me happy.

[@laszlogulyas6422]

What if: particles are 4 dimensional objects. We can interact (through measurement) with only their surface or 3 dimensional apexes. When we interact with them, the whole multidimensional object starts moving until only one 3 dimensional part of it remains in our 3 dimension. (i.e.: imagine a triangle crossed by a line through 2 different points. The line is our reality the triangle is the multidimensional particle. When the measurement starts the triangle starts moving until the crossing line reaches its closest apex). This explains the 2 slit experiment: normally our 3d reality can cross the multidimensional object (photon) at different points. Measurement forces the object to spin until its closest apex perfectly fit into our 3d world. Quantum entanglement is a different topic. Imagine the multidimensional object like a container which contains different spins. When 2 particles are "separated" and "quantum entangled" they are basically 2 different 3d part of the 4d object. When you observe one part then you interact with the 4d particle and you influence its spin. It works like electro magnetism: when you places a postive current to a closed object that contains mixed charged particles, then it will forms a negative polarity at the closes point to positive current outside of it, and also forms a positive polarity at the opposite side. This can work because the 4th dimension is a layer of information, where no matter is stored. Transferring information from this dimension to 3d reality can influence it just like how electricity works. The 4th dimension look like a fluid cloud of information, and the 3 dimension of matter works like a blockchain that stores the important definite states of the 4th layer objects following a cause-effect ruleset that can't be changed.

[@kunalbhardwaj9060]

Dude this is actually a plausible theory. You should post it somewhere. This is so underrated

[@cheekeebreekee]

Good read.

[@kennguyen5753]

Write a paper on it

[@xrsphere]

This theory actually makes the whole notion of an object existing in simultaneous states more plausible in my head. Thanks for sharing

[@RemyRut]

Great thought. I've wondered if the Calabi-Yau Manifold doesn't play some part in exactly what you're describing. There are just extra textures and dimensions in space we can't see. Particles are moving in and out of these spatial dimensions, so the appearance of a probability wave (and it's collapse) is actually just normal movement through extra dimensional space, and the act of observation entangles it with us, with our higher dimensions, forcing it to emerge and "pick a side" so to speak.

[@bockmaker]

If a tree falls on a mime does anybody care?

[@Tom-fh3zg]

yeah hate to lose a tree

[@Butmunch666]

Might have just been an old tree that lived a long happy life and it was just his time. :)

[@bockmaker]

That would violate the Clown exclusion principle. Rodeo clowns maintain a bull to clown ratio. No known upper bound of clowns in a car. But their can only be one mime per stage, other wise the masses become enraged.

[@menachemsachemrobotscowitz2794]

You really don't need the tree. Just the mime pretending there is a tree.

[@ddmagee57]

You're profound, bockmaker!

[@benalkan8559]

I love the casualness with which you're talking about the wave function. I'd love to see the reaction of anyone who feels that they are capable of handling the pure maths behind all of the claims

[@loturzelrestaurant]

Know Sci Man Dan, the Science-Man?

[@SharaTheEmpress]

So glad I found this channel

[@charlesmcmillion5118]

The Great Physicists' Road Trip by Ms. Rachel C. Millison Great physicists and a few of their friends from the past decide to return to Earth for one last road-trip vacation to the coast together. They all appear on Earth on the designated evening. Heisenberg pulls up behind the wheel of a gigantic 1930's car, a huge grin on his face. As they're getting in the car, Hubble looks up and says "What a wonderfully dark sky". "Shouldn't be" responds Olbers. "Always has been" says Hoyle. "No, it hasn't" says Lemaitre. "I knew that!" says an embarrassed Einstein. Once they're all in, Teller says "Hey guys, this trip is going to be The Bomb!". "Yeah, but why do I always have to organize?" asks Oppenheimer. "Where exactly will we end up?" asks Kepler. "That's impossible to predict" says Bohr. "I just can't believe that's true" says Einstein. Heisenberg punches the throttle and the old car roars off. "Say - this thing sure accelerates" says Newton. "I don't know, Isaac. It feels like gravity to me" smirks Einstein. Later that night, as they are speeding down a country road, a police car catches up to them and pulls them over.[1] "Do you know how fast you were going?" the cop asks. [1] "No, but I know exactly where I am" Heisenberg replies. [1] The cop says "You were doing 55 in a 35" [1] Heisenberg throws up his hands and shouts "Great! Now I'm lost!" [1] The cop thinks this is suspicious and orders him to pop open the trunk. He checks it out and says "Do you know you have a dead cat back here?" [1] "We do now, a**hole!" shouts Schrodinger. [1] "I think it's time to split" says Everett. "Scatter!!!" yells a panicked Compton. "Say, officer - how did you manage to spot us on such a dark night?" asks Hubble. "I saw the light from your head lamps" says the cop. "How fast was *it* going?" asks Michelson. "That's simple addition" giggles Galileo. "Not exactly" says Lorentz. "Look here" says Heisenberg, "how do you know I was going that fast?" "I clocked you over a measured distance" says the cop. "How frequently?" asks Hertz. "I disagree with your measurement, officer" interjects Einstein. "Don't start tonight, Albert" says Bohr, shaking his head. "What Herr Einstein is trying to say" continues Heisenberg, "is that time was running at a different rate for you than for us because we were moving relative to you". "WHAT??? I should have realized that!" exclaims Newton. "I discovered it first" interjects Hooke. "It's true" says Maxwell. "We're all famous scientists and, believe us, Herr Einstein proved it, though it came as no surprise to me". "Must have been a real eureka moment" nods Archimedes. "Extraordinary!" says Galileo. "Extraordinary evidence" asserts Sagan. "Well, it sounds awfully complicated" responds the cop. "Not really. I'll draw you a simple diagram" says Feynman. Totally flummoxed, the cop lets them go with a warning. As he drives away, Doppler cocks his head and listens to the sound of the receding police car. "Gotta love that" he says. "Amen" responds Hubble. Returning to their car, Lord Kelvin remarks "Sure is warm tonight" "Yep - lots of disorder" replies Boltzmann. "In places you'd never expect, Ludwig" adds Hawking. "I was lucky to get away with that" says Heisenberg. "Most cops think they're better than everyone else". "Yes - I hate inequality" adds Bell. "Though you *were* speeding" says Faraday to Heisenberg. "I carefully observed the needle creep from 35 to 55". "Actually, it went up in jumps, Michael" replies Planck. "I couldn't see it because of the condensation" says Bose. "Please keep it under 0.07, Werner" says Mach. "In which frame of reference?" asks Albert. "Hey, Max" says Heisenberg, "If you loan me a tiny bit of money, I'll pay it back so quickly you'll never notice it was gone". As they pile back into the car, Bohr says "See here - you must fill the seats in order - no empty spaces allowed. And stop interfering with each other!" "Only one of you can sit next to me!" yells an agitated Pauli. "I need my own space" grumbles Minkowski. "Say, Werner - it's stuffy in here. Be a good chap and crack the window a bit" says Hawking. "Sorry, Stephen. It can be all the way up or all the way down, but nowhere in between" replies Heisenberg. "Hey guys - Albert and I just figured out a great shortcut. Only one bridge" announces Rosen. "It will save us a lot of distance" says Einstein, "but it might get spooky". "We could just tunnel" says Hund. "I prefer left-hand turns" says Madame Wu. Arriving at the beach the next morning, they hurry from the car and stand looking out over the ocean. "Look at the wonderful waves" says Schrodinger. "They don't look like waves to me" says Bohr. "This is not my idea of a sea" opines Fermi. Looking down at the fine sand, Dirac exclaims "Look at all the particles!" "Now *those* look like waves" says De Broglie. "This is great!" exclaims Feynman, rubbing his hands together. "Now, lets go meet some girls!" "Sounds good to me!" exclaims Schrodinger. "I'll show them my screw!" boasts Archimedes. "Let's delay" says Wheeler. "We have to be discrete" warns Bohm. "We need to conserve our energy" says Mayer. "I'll go, but I can't interact" says Zwicky. "I need to shave first" says Occam. "What are girls?" asks Newton. 1 Based on, and including the original joke attributed to Rich Granger, Engineer, Battelle.

[@a-zsensation8633]

Awesome....... I mean all the modern and some of even the unknown scientists like Compton, Olber and many others..... It was fun reading this

[@madhavjha945]

It great ...you done a tough job to share ...

[@dallyh.2960]

👏👏👏

[@globalwarming08]

As a human, I don't want to go into quantum's world because I will feel totally dumb. I am good in my matrix style simulated universe.

[@MrHHVV]

Actually, i think this could be prove that we are in fact in a sim universe. Something not existing unless observed might be a way for "God's" computer to save up some ram by not having to render it to be real unless observed

[@gregedgerton3390]

Thank God you tied this-up with 'many worlds'; and it relaxes people's ideas about dimension and their dependence upon their notion on linear space-time. I wish that the guy would read the comments. There some great questions here. Including my own 🤯.

[@jessstuart7495]

The wavefunction description of particle behavior (position, momentum, polarization, etc) reminds me of complex conformal mapping. I wonder if in the development of Quantum Mechanics we latched onto a complex-probability view, when there could be a duel equivalent description (like in conformal mapping problems) that doesn't invoke our typical notions of space and time (locality), that would provide more insight into some of the quantum weirdness.

[@velorien9965]

me: wipes an entire person from existence and creates a whole new person out of nothing causing infinity density and a blackhole me:ha ha lol

[@NichoTBE]

I've always been interested in quantum entanglement since I heard about it years ago, yet even when I see the simplest of explanation i still do not know what it means or the implications/applications are to science.

[@Tom-fh3zg]

yeah I agree, how do they get entangled, how do you move them apart, I thought we can't even see a single electron let alone flip it measure it poke it and prod it

[@gamerN77]

Well, people do say that "if you think you understand quantum physics, then you don't understand it" :)

[@garethdean6382]

Basically they're two particles that behave like they were one, linked somehow.

[@garethdean6382]

Entanglement usually requires two particles to be created in the same event. Electron-positron pairs can be made from energy (photons) for example, the opposite of matter-antimatter annihilation. They'll move apart naturally by themselves. We can't 'see' electrons with light, but there are a lot of things (like magnetic fields) we can't see with light. We *can* measure single electrons in lots of ways, old TV 'cathode ray' tubes for example just fired them at a screen to make it light up.

[@dutchrjen]

The simplest way to explain it. 1) Quantum mechanics requires things to exist as spread out "waves" AKA to exist in all possible states they can exist at once. It's weird but summing up all possible states results in cool shapes verified by experiment (like the shapes of electron orbitals AKA the shapes of atoms). 2) Physics requires that things like angular momentum, linear momentum, lepton number, etc are exactly conserved. Now take two photons get them to interact to create a positron electron pair. The photons are ALWAYS integer spin and they MUST have a total of 1, 0, or -1 and electrons or positrons are always either 1/2 or -1/2. If you shoot photons that you know have a total spin of 0 and create the positron-electron pair we know that one will be spin 1/2 and the other -1/2. WHY? The angular momentum (spin) must be the same as we started -the initial and final momentums must be the same. HOWEVER, quantum mechanics says the states are blurred and BOTH particles are BOTH spin up and spin down until an interaction fixes them a certain way. Note: no entanglement occurs if the initial total spin was 1 (or -1). This is known as a "Triplet State" where no entanglement occurs (the entanglement state is the Singlet State). Having a single particle existing in all possible states is weird but doesn't tell us much experimentally. HOWEVER, when two particles must together conserve some quantity AND exist in a superposition entanglement occurs. If we have some situation where we know the initial angular momentum was exactly 0 and we know the daughter particles are an electron and a positron then we know these two particles are entangled. If we measure one particle we are certain of the spins of both particles. However, this certainty will quickly diminish because environmental noise can wash away the entanglement. What many think occurs is when particles further interact with the outside environment they further entangle with those particles obscuring/complicating the original controlled entanglement in unknown ways. This decoherence is a large limiting factor.

[@meandyours]

I think there's indeed a way to save locality but change it from spatial locality to objective locality. What I mean by this is that a wavefunction of no matter how many particles will count as a single object, and therefore, the whole thing will be affected when only a part is affected. This "should" work because the object I'm talking about is some fundamental particle in a wavefunction and not an object made from many particles that aren't in a wavefunction together.

[@wesjohnson6833]

Entangled particles DO share a single wave function. But that wave function is still space like separated. It's being instantaneously defined is non local.

[@Nortonius_]

Made me think about the sophons in Liu Cixin’s Three-Body series

[@aliciabaumgartner1406]

So the spins of an entangled electron-positron pair are always opposite if they're spontaneously created from a photon. What would be the result of measuring the spins simultaneously with two measurement devices with axes perpendicular to each other? If a measurement of the spin of a particle is always parallel to the axis of the device, then the spins of the entangled pair would be measured to be perpendicular to each other. How does that makes sense given the first statement?

[@terryfuldsgaming7995]

because the entire entanglement theory is based on flawed measurements made by flawed equipment. I don't think it's real. it's an artifact of the way we measure, not a real result.

[@96mtbrider]

Do you want the universe to explode?!

[@AhsimNreiziev]

To be exact: the Spins are always opposite *if they are measured along the same axis*. Usually, unless the axis chosen is fully horizontal _[and even then if you want to avoid confusion]_ one direction along the measurement axis is labelled "Up", while the other is labelled "Down". If you measure them at axes perpendicular to each other, there is a 50% chance both will be "Up" along their respective axis, while there is also a 50% chance they will be 'opposite', with one pointing "Up" along it's measured axis, and one pointing "Down" along the other axis. In fact, Bell's inequalities were derived from a scenario with 3 axes, which were at 120° angle with respect to one another, which, assuming the Spin can be influenced non-Locally by means of the first measurement, gives a 75% chance that the Spin result will have the "same direction" when they are measured along the first axis, compared to a 0% chance when measured along the same axis. Since across all experiments, 2/3 of them will feature measurement along different axes, the total ratio of "same Spin"' vs "different Spin" should be (3.4)*(2/3) = 0,5, so 50/50, in this scenario. On the other hand, it turns out that when Spin *can't* be influenced non-Locally, the percentage of "same Spin" across all pairs measured should lie between 0% and 4/9, so never reaching 50%, giving a neat little distinction between the two possibilities. The results of experiments show that the distribution is indeed 50/50, so if you want to keep Reality, you need to give up Locality. Of course, Einstein, Podolsky and Rosen's Thought Experiment _[aka the "EPR Paradox"]_ showed that if we should *abandon* Reality, we *also* need to give up Locality. This is where Bell's "opinion", which is actually fact, that the two together show that Entanglement is non-Local came from.

[@tuipale]

And i believe that Einstein was only scared to express any real opinions about quantum mechanics. Thats an easy way to lose your job and nobel price back then.

[@FutureChaosTV]

Sandy Crotch That is the point: we can't meassure instantly two points in spacetime to an "absolute" degree and if I understand this right, this is also denied by Relativity.

[@sirkowski]

The boring world of Niels Bohr. (Simpsons ref)

[@JimboJamble]

Really? I was pretty Bhored.

[@BIGTTSNORLAX]

I am very compatible with your way of teaching, and I really enjoy your content!

[@mrmellon5228]

When a bipolar string breaks, the event happens to both ends at the same time. We just see the ends as particles (multiple strings reverberating together) change states based off the resulting ends of the entangled (broken) strings affecting those particles in opposit ways. Just a thought

[@rvx5818]

I love this channel so much

[@rubiks6]

Are there pebbles and grains of sand on planets spinning around stars in galaxies far, far away, even though we could never, even in principle, ever observe them? ---------------------------- Conversation overheard with German accents: Niels Bohr - "If a tree falls in the woods and there is no one there to hear it, does it make a crashing sound?" Werner Heisenberg - "I know exactly how fast I am going. I just don't know where I am." Erwin Schrödinger - "Of course, I know the tree has fallen. You just told me!" Albert Einstein - "I have a relative back in Düsseldorf who thinks it was a different tree." Werner Heisenberg - "I _still_ don't know where I am." ---------------------------- Okay, seriously ... (12:55) "We're on the verge of creating synthetic life ourselves." Are you kidding?! We can't ever create a self-replicating Lego machine.

[@dancrane3807]

We have created self-replicating Lego machines. They are called kids, and cause us to buy more and more Legos.

[@ChickSage]

Probably, but those aren't subatomic particles. The thing is, if it's something we could never observe, how could we know whether it exists or not?

[@rubiks6]

@@ChickSage - Mmmm ... okay. What's your point?

[@ChickSage]

@@rubiks6 I was actually just responding to your question, as it related to the video. Your question got me thinking that, though, the principles of quantum mechanics can apply to everyday objects, everyday objects don't usually behave like subatomic particles. I also thought about your question philosophically. If something exists, but we can never observe or confirm its existence, then it has all the same characteristics as something that doesn't exist. Thus a strong argument can be made that perception is reality, for all intents and purposes.

[@shiddy.]

as far as videos on this channel that are 'must watch' this one is very high on the list

[@robotex82]

Thank you for all the content you have been publishing. I love it! Can someone tell what the background music is at 3:45?

[@alexb3617]

why everyone believes that wave function in quantum physics proves that reality doesn't exist without observer? that tree disappears when no one is looking at it? there is other explanation in macro world, many things are effecting each other, locking them in place and forcing their wave function to collapse. so its not our opening of eyes that collapses their wave function. something else does. why is that so hard to get? does it have any counter argument? it also explains non locality perfectly

[@fireballgamer4699]

Alex B the wave function doesn’t collapse until we observe it

[@DeathBringer769]

It's because people misunderstand what "observer" means in this context. Makes me laugh but makes me a bit sad too.

[@ethangray8527]

From my understanding it collapses not because we observe it, but because we interfere with it in an attempt to observe it.

[@rangahatimamungoyumtirumga1203]

It's not their fault, it's the fault of scientists constantly, casually patronizing young minds by just telling them that OBSERVING quantum phenomena collapses the wave function, but refusing to actually clarify what they mean by "observe." They are believing the science they are taught. It's the fault of the teachers for lazily using the word 'observer' nonchalantly without bothering to specify EXACTLY WHAT THEY MEAN by something 'observing'/collapsing the wave function, i.e. what are the exact, actual, specific criteria. I actually still don't even know and I've been watching physics videos since I was young. Because none of the big channels will explain it. None. They just wave it off like it's too complex to get into and we should just take it at face value.

[@ethangray8527]

+Lil Soybean Hold up right there. So they just believe whatever a teacher tells them to and you expect us not to judge them?

[@MichaelLloyd]

Why couldn't my high school Physics teacher have been this good?

[@johngrey5806]

Maybe because he had inferior eyebrows?

[@MichaelLloyd]

It was so long ago I don't remember if he even had eyebrows :o)

[@Karhald]

Same. But my high school Physics teacher couldn't grow a proper beard either. So that's a huge handicap he was dealing with from the start.

[@subh1]

This is a popular-level video without the math and details. That really is not what makes up physics. You won't be able to write a single academic paper, nor solve a single problem in quantum mechanics by watching videos like this. These videos, and their hosts, are meant to inform and entertain, not serve to be pedagogical.

[@cluckeryduckery261]

i was lucky, my high school physics teacher was awesome. one of those teachers that gets you engaged in learning, not just quoting from a text book. come to think of it my 7th grade science teacher was like that too... huh. guess i got lucky, definitely put fuel on the fire for my love of science today

[@jeevanforlife]

so well explained. very helpful to understand

[@user-sd3ni4fi9x]

Beautiful presentation!!

[@reginaldsantos1829]

It’s the like the universe’s power-saving mode.

[@alyasl.3350]

It is though; principle of least action.

[@AFastidiousCuber]

Isn't superdeterminism another solution to this problem? I'm not an expert, but, in a quote from Bell, he said: _"There is a way to escape the inference of superluminal speeds and spooky action at a distance. But it involves absolute determinism in the universe, the complete absence of free will. Suppose the world is super-deterministic, with not just inanimate nature running on behind-the-scenes clockwork, but with our behavior, including our belief that we are free to choose to do one experiment rather than another, absolutely predetermined, including the ‘decision’ by the experimenter to carry out one set of measurements rather than another, the difficulty disappears. There is no need for a faster-than-light signal to tell particle A what measurement has been carried out on particle B, because the universe, including particle A, already ‘knows’ what that measurement, and its outcome, will be."_

[@garethdean6382]

Yeah but that sort of destroys the basis for science, he also said '[W]e always implicitly assume the freedom of the experimentalist... This fundamental assumption is essential to doing science. If this were not true, then, I suggest, it would make no sense at all to ask nature questions in an experiment, since then nature could determine what our questions are, and that could guide our questions such that we arrive at a false picture of nature.'

[@neeneko]

superdeterminism does not really add or subtract anything from the problem. It only becomes a useful framework if super measurement is also a factor, but we do not have that. Physically there is a good chance that superdeterminism is indeed the underlying mechanic, but the parameters it depends on are beneath what can actually be measured, so it is a useless framework. QM works fine in such a model, all of the probabilities and wave functions come out exactly the same... and that is the problem, they come out exactly the same.

[@xnoreq]

A much simpler idea is that reality simply cannot be tricked. If you measured one and the other one did not have opposite spin it would be a violation of angular momentum. Reality simply forbids that. The easiest and cheapest way (maybe only possible way) to do that is to have the other entangled particle have opposite spin. That's why two entangled particles are mathematically one and the same.

[@braddavis4377]

I've been wondering, can quantum entanglement be used as FTL communication? Also, can QE be used to discover the physics inside a black hole? Thanks!

[@nutsackmania]

These are excellent videos.

[@Alchemistic88]

This channel makes me proud to be a human. To think we've gotten to this point of deciphering and understanding quantum physics, it's magical. I really hope I'm alive to see some real breakthroughs in this space. I am just in awe of the minds that were able to bring us to this point. Such a great explanation too 😊

[@jimmydavis2057]

Everyone says the "spin" of particle is not real and a electron has 1/2 "spin" so what do we actually mean by "spin" at a quantum level?

[@garethdean6382]

In general it's referred to as 'spin' since it relates to angular momentum. (How much it will make something that *can* spin spin when absorbed.) This leads to weird things like the 1/2 spin meaning an electron needs to be turned around twice before it gets back to its original state. *This* leads to claims that spin is not real. However you *can* view a spin as being a real property; as a polarization of energy in a wave (which all particles behave as.) This paper gives a more thorough description: www.physics.mcmaster.ca/phys3mm3/notes/whatisspin.pdf

[@thstroyur]

"Spin" is an abstract group theoretical concept: it refers to the way fields transform as reps of the universal cover of the Lorentz group (i.e., it's relativistic - though you may actually trace the core of the idea to the more mundane SO(3) -, which is why they're so akin to rotations. When you quantize the field, the spin accordingly becomes an observable with discrete (eigen)values, and follows the familiar algebra of angular momentum. Experimentally, we observe it as "excess" degrees of freedom: if all things equal a particle can have 2s+1 different states (you can see the this with e.g. a magnet), then you say you have a particle of spin s. What I've just said is actually more general than spins: it's the logic that people used to postulate the existence of colors (QCD).

[@vatsalyasharan4202]

Actually there is no classical analogue to that spin thing. There's no way to describe that "spin" in any classical sense

[@russellesteban]

5:09 if the arrow on the right (red/green) thing looks weird, thats because the part of the arrow w/ the arrow head is supposed to be partly hidden by the thing, while the other partly hidden backside of the arrow is supposed to show on top of the object.

[@thorstenwestheiderphotogra7722]

Fantastic channel!

[@theveremianshow2101]

Hey there buddy PEEKABOO

[@waltonsimons12]

AHHH! That's hilarious! How'd you just appear like that?

[@milanstevic8424]

psshh _the guy seems to be entangled_

[@redaabakhti768]

laughed for 5 minutes at this couldn t hold it

[@fancyghost7358]

He said it when I red it. 😂

[@ajezaseden]

Isn't using the word "measurement" or "observation" problematic in this context, as it kind of implies that WE as in humans are what's needed to make this "observation". But really, if I understand correctly (and I think you allude to it @ 7:45) any kind of interaction with any other particle is enough to break this entanglement. I know you know more about this stuff than I, but I do think its these kind of things why quantum is used as a "buzz" word in all the spiritualist bullcrap. I just saw an ad for "quantum yoga" at my local yoga place yesterday, what are they doing there just randomly appearing and disappearing all over the place in different yoga positions?

[@maruchannuudle657]

Yoga superpositions*

[@OnlyKaerius]

Any "measurement" or "observation" at quantum scale is performed by interfering with the measured/observed thing. Whether bouncing one particle against another, subjecting it to an magnetic field, or intercepting a wave with a reactive material. We cannot "see" anything at that scale, and indeed, to see involves intercepting photon wave particles with a material that reacts to very specific photon wave frequencies, we "see" by the brain interpreting a vast number of these interceptions, against molecular structures that are specifically sensitive to certain ranges of frequencies, what we call red, green and blue.

[@pigsbishop99]

I think that Matt is very conservative in his approach. Others are well comvinced about the importance of the observer, for example.

[@AquaTeenHungerForce_4_Life]

Oh sure, it may say "quantum yoga" on the doorsign. But until you go through the door, can you really prove what they are doing in there?

[@WilliamFord972]

THANK YOU for stating this

[@ozzyperez3190]

This channel.is life. Thanks for all.u do buddy.

[@1dir951]

@PBS Space Time this discussion introduced an incomplete part of Bell's proposal--Superdeterminism. Search KZbin and view: "Entanglement Theory may Reveal a Reality we can't Handle" by Arvin Ash

[@deeeeeeps]

I always pictured everything working this way. Then I found about quantum mechanics and I'm blown away that there is a lot of science behind it!! Now I can't stop watching these shows.

[@alexanderjonsson5749]

That the universe exist independent of the mind of the observer

[@TheNameOfJesus]

TL;DR, The explanation at 9:50 was my first reaction when I first learned about quantum entanglement about a decade or so ago.

[@torchgoat1707]

i love the video thank you i had to subscribe !

[@Yelkwood9]

What if you had a lab on pluto with one of the entagled particles and one on earth with the other and basically earth says 'right, at some time between 9:55 and 10:00 we're going to influence your particle.", then at the same time, they send a message saying they've done it, but the folks on Pluto already knew by the time that message arrived hours later. wouldn't the 'information' of exactly when it was in that time frame be communicated faster than light?

[@proshiv1]

Yea that's what's so spooky about it. It's faster than light, it has no speed because its instantaneous

[@PHooMAA]

Nah. The lab on Pluto would always see a particle in a collapsed state, regardless of whether the lab on Earth has measured their particle or not. This is because in order to check if the Earth particle was measured, the Pluto lab would have to measure their particle. Thus, no information is transferred.

[@Fr3nchNerd]

No, because you can't know the state of your particle unless you look at it. So you don't have any possibility to know that it has "changed". So the only information that you have is that the state of your particle is the "oposite" of the other one, and you only get this message with the message from earth. So, no, it's not faster than light communication.

[@xnoreq]

No, there is no faster-than-light communication of information. Knowing that the other side has the opposite spin that you just measured is not transferred information since the spin you measured was random in the first place.

[@AlexActually]

There's no 'information' being transmitted. If the Pluto lab observes their particle, they collapse the Earth particle as well, so there's no way for them to see if the Earth lab has made their measurement without waiting for the communication. Despite the particles interacting with each other, causality is preserved since no information oa transmitted.

[@ishel9210]

I travel all of time. In and out. I can say this because no one would believe it.. and that's a blessing.

[@HelloJosieLiz]

Ish El please explain. We want to know more

[@apocalypseplough8089]

Just watched the PBS NOVA show about it. Something only exists if we look at it or measure it. Blows my mind.

[@berkeleyedit7852]

I find this absurd. It makes humans the center of the universe, the creators of the universe. I'm no Einstein but if people by measuring something cause it to come into existence, what does it mean if we study ourselves?

[@avinashreji60]

I think people misunderstand the meaning of “observer” and “measurement”

[@medexamtoolsdotcom]

Whole new meaning to the words "pics or it didn't happen".

[@colindupee]

Have we verified that the bell inequalities are violated for particles that travel slower than light (such as electron/positron)? I ask because there is another possibility: To an object moving at the speed of light, the universe has no length, and it takes no time to travel from one side to the other (because there is no travel). In their own reference frames, entangled pairs of photons are still in the same place. In this case, you might expect tweaking one would instantly tweak the other. This obviously can't be the case for objects with mass, like electrons.

[@davidturner9827]

Colin DuPée Yes it has been verified for electrons, see e.g. Hensen et al (2015), Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometers, Nature 526 pp682-686

[@jvincent6548]

...but the speed of light is finite. the universe is not.

[@texashankpalmer876]

@@jvincent6548 If I understand correctly he means that light experiences no time, it can't in fact, since it is traveling at the speed of light (obviously). So the light, in relation to itself, takes no time to reach the end of the universe.

[@jvincent6548]

@@texashankpalmer876 It is breaking laws of physics then. Light's photons travel at 3 x 10**8 mps. Right? So light experiences time and that is why we say 'so many light years away', for example.

[@texashankpalmer876]

@@jvincent6548 No that's actually what the laws of physics tell us. The light from our prospective does take time to get from point A to point B. Light from it's own prospective doesn't experience time. Take a look at this, kzbin.info/www/bejne/d3S4pnmdbr5smrs He explains it much better than I can.

[@CstriderNNS]

i like E8 theory " All time is effecting all time, all the time "

[@lucianilie2397]

another amazing video, thanks

[@nigelgriffiths5747]

You keep punching out great videos , top marksman