Is 'Perpetual Motion' Possible with Superfluids?

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The weird rules of quantum mechanics lead to all sorts of bizarre phenomena on tiny scales- particles teleporting through walls or being in multiple places at once or simultaneously existing and not. Shame all this magical behavior doesn’t happen on scales large enough for us to see. Except that there is a way for us to see large-scale quantum weirdness, and that’s Bose-Einstein Condensates & Superfluids.
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Good luck with the algorithm, PBS Space Time.

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always

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What.... there is a new sub category? WTF is this trash? I thought I was subbed totally, but I was just on 'personalized.' I switched to 'All.' Or am I super dumb and this has always been the categorical subscription statuses??//////

Haha, it was always ALL for you guys

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Thank you for your continued product 🙏😌

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when do we get an episode on how tf dust accumulates on a fan?

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Probably sticking from grease?

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@@maniacpwnagekinghuman grease.

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MAGIC. This is a science channel, you'll get no answer to that mystery here.

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My first guess was electrostatic.

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Air oils and imperfections

[@waltwimer2551]

I'm a 56 year old electrical/computer engineer and long time "physics enthusiast". As such, I've been aware of the existence of superfluidity for a long time, but this is the first time I've encountered an explanation of the underlying cause of the phenomenon. Excellent! Thank you, Dr. O'Dowd and PBS Space Time!

[@JB-pu3oj]

Can't agree more! This was so understandable for a layman like me.

[@subliminalvibes]

The black and white Alfred Leitner videos on KZbin also explain the phenomenon in quantum detail. 👍😎

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It never occurred to you to look at the Wikipedia article? Might want to try it.

[@jimsmith3715]

Thank you for an informed response :)

[@dylangreen6075]

Dude... This was a serious lightbulb moment for me. Fermions taking on the qualities of bosons at larger scales. This has given me a much deeper understanding of those phenomena. Thank you!

[@PandemoniumMeltDown]

This dude as well. Now I know I wasn't crazy when I said this beer glass was deffective, yet I now think beer might be a superfluid, sometimes.

[@fensoxx]

This was a big episode for me as well. I may watch ten in a row and not have a personal breakthrough but when they happen it’s great.

[@jeremy4ags]

@@PandemoniumMeltDown if you drink enough beer, your head will be perpetually spinning

[@PandemoniumMeltDown]

@@jeremy4ags I drink far from enough.

[@pwinsider007]

If you try to push fermions to same state then it will apply for e that can resist dead star collapsing into black hole then which fundamental force do fermions apply ,is it electromagnetism?then how does star collaps into black hole if fermions apply force that stops the collapsing

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When the ultra-non-provocative _PBS Space Time_ is having problems with the algorithm, you know YT is going the wrong way. ⬇

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I often wonder if channels like this were as popular as the idiotic Mr beast videos... Jame Charles. Kim kardashian... how much better the world would be.

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I would trade all of them for all the PBS channels... spacetime, eons, etc. Numberphile, scishow, sci show space, crash course, moth light media, atheist experience, thinking atheist. "Smarter every day" isn't that good imo even tho the guy is nice enough... "Be Smart" is sorta the same but better than smarter every day.

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why? A video about something everyone with a 4th grade education knows about is "great" how?

[@zaddyjacquescormery6613]

@@protonneutron9046 I am VERY curious about which part of my comment pertains to something “everyone with a 4th grade education knows?”

[@protonneutron9046]

@@zaddyjacquescormery6613 I wrote the sentence at a grade school reading level. It is self explanatory.

[@BezBog]

I’m still paying off my bachelor physics degree where I took an entire course on surface physics and superfluidity/superconductivity. This video did better at explaining the phenomena in 15 mins than a full semester of my German big-brain professors

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Watching KZbin > Going to College

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i have always said that current educational systems are on the line of obsolete and intentionally complicated to make money.

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problem is: Which information that you see is legit, and what is WAY OUT there BS...This guy is NOT shy about new trends, but,...tends to avoid reasonably suspicious BS - which is useful for students... Alex Sophia Aguilar has a point that some try to ...well you know, I suggest you watch Edward Teller's video, “Edward Teller - Going to see Einstein give a lecture (31/147)” ... and enjoy it - since he obviously agrees with you!🙂@@AlexSophiaAguilar

[@actually5004]

I bought a pneumatic air file to fix body work on cars, it was expensive and I only need it a few times a year but I still don't envy your expensive and also completely unproductive tool.

[@mgold7503]

I really like how you showed clips of a superfluid. It really helps me to get the visual and understand.

[@DanHarkless_Halloween_YTPs_etc]

Yeah, and getting to watch superfluid freely leaking through the bottom of a solid glass container was pretty amazing!

[@EthanTheWerewolf]

That super fluid broke my brain

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This channel is such a gem, I'm glad it exists.

[@hikingpete]

I've really appreciated the recent explanations of fermions and bosons, and statistical mechanics.

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Great to see you guys taking on condensed matter physics subjects

[@GeoffryGifari]

for reportedly having the largest number of physicists working on it, condensed matter seems strangely underrated and underrepresented in popsci

[@yeetyboi5481]

​@@GeoffryGifari because it's super goddamn boring compared to literally any other aspect of physics

[@GeoffryGifari]

@@yeetyboi5481 no.

[@quentinfenoy8412]

​@@yeetyboi5481hell no! This is because you don't know the field, but did you know that electrons, that are elementary particles, so that they cannot be divided into other particles, actually can in condensed matter systems? This is known as fractionalization and it is juste one of all the impressive aspects of condensed matter physics! If you like quantum physics, you'll love condensed matter physics.

[@quentinfenoy8412]

The field is underrepresented in popsci because it is really difficult to explain people that have not a solid background in physics!

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I love PBS spacetime

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I love watching these video's even though I don't understand 99 percent of it.

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I'm with you brother

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@@7Alberto7even less in my case.

[@renegibbetnich7883]

Each time, you understand a little more.

[@pink_plasticbag]

this is the best explanation of Bose-Einstein Condensate, blows my mind the whole way through. and it feels unreal like a glitch IRL that we're not supposed to see. simply amazing!

[@FleshWizard69420]

"it's not a bug, it's a feature"

[@brenorocha6687]

I heard many times about the weird behavior of supercold helium. But no one ever tried to explain to me in lay terms, neither did I believe that I would be able to understand the explanation. Until this video. Clear and accessible explanation as usual. Probably also because I've previously watched all the videos you mentioned. Thank you!

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Gotta love the random YT algorithm punishments!

[@martinstent5339]

12:12 It seems to me that you couldn’t “stir up” a cup of superfluid helium, because it would effortlessly flow around the spoon. I think you have to warm it up above 2.1K, stir it and then cool it down again while it is still rotating to get the “never-ending” vortex.

[@fascistpedant758]

If it still has mass, it still has momentum and would still require a force to accelerate it away from it's position in front of the spoon.

[@ExternusArmy]

@@fascistpedant758 yes but that has nothing to do with what he said. Of course a force is required but the energy dissipation in viscosity is 0 meaning it could rotate endlessly once it is accelerated. The only problem is it would flow around the spoon without viscosity to generate the motion in the first place like OP said.

[@mb1287t]

​@@ExternusArmy perhaps it can be spun with gravity.

[@nsacockroach4099]

You still have the pressure in front of and the under-pressure behind the spoon. So I'd imagine it would still start spinning since this pressure differencial transfers momentum despite the frictionless flow around the spoon.

[@EebstertheGreat]

You can still stir a superfluid. Superfluids still interact with other things. Consider that if you carry a cup of superfluid helium around, the helium will move with the cup, so clearly the walls are pushing on the liquid. You can push on the liquid with a spoon instead, and that will cause it to move forward. And then there won't be anything to stop it, so it will just keep going.

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Best science channel IMO. doesn't hurt that Matt explains things so well, also doesn't hurt that hes easy on the eyes :P

[@thulium_3169]

fr

[@leftysheppey]

I wouldn't mind him spending time in my space :)

[@erdngtn9942]

The picture of the atom shadow behind the "bose-einstein condensate" was a nice touch to the graphical editor

[@AlienScientist]

Superfluids are awesome... I remember learning about them 20 years ago as a physics undergrad and becoming fascinated with the concept.

[@GeoffryGifari]

that resistance two fermions give when forced to be in one state seems eerily similar to a "force", even though it arises purely from statistics and not from an interaction (like the standard model)

[@MrOvipare]

Exact, it's a quantum effect that is observed statistically. It's called "exchange interaction" and is responsible for phenomena like ferromagnetism, for example.

[@aaronm6675]

Great video, as usual. Love the emphasis of superfluidity as a macroscopically available quantum effect that's weird and direct

[@Mohammad__M__]

15:47 "Oh I'm so tired of this joke" 😂 We appreciate your ever increasing effort to keep making these jokes!

[@eric_james_music]

thank you so much i've seen a couple other vids about this and didn't understand. the quantum physics backstory with visuals helps a ton. been subbed for this channel for almost 2 years, love it. keep it up!

[@mb1287t]

Favorite episode in a while. I wish there was more of it

[@samwisegamgee4659]

PBS-NOVA did an excellent 1 hr episode on this subject a few years back. However, they were aimed at a less scientific audience and it was nice to see you visit it on a more technical (Quantum) level and provide a more in-depth explanation of the phenomenon. Good job!

[@eltodesukane]

Probably this one: NOVA, Absolute Zero 2-The Race for Absolute Zero (2008-01)

[@formlessone8246]

NOVA used to be great... when I was a kid. But I swear, not only did they slowly dumb things down, but the show started padding it's runtime with repetitive repetition of things they had said twelve times already, as if they were afraid you didn't understand the first two, or that you were necessarily tuning in just now. I think the first time I noticed was back when they had Brian Greene trying to explain string theory, and they never did explain what the string was made of (though that is partially because there is no good answer). Spacetime has always managed to get to the point, if only because they know they can always direct you to an old video or you can replay the one you are on. Which means he can get more technical at least some of the time.

[@apollion888]

Using the show title at the end, instead of a "Space Time" reference to the totality of existence, is tricky, but this episode pulled it off Good work

[@novakonstant]

as always, absolute masterclass. Beautiful insights on the fermion/boson interactions through spin. I feel this episodes gave me the insight to correlate all the information from your last 2 spin/spinors video.

[@chipgruver2911]

So, you want us to cool this episode down to 2 Kelvin, reducing the friction created by the KZbin algorithm to zero. We should avoid heated comments and allow the flow to swirl forever in this Space Time!

[@brothermine2292]

Well, at the very beginning of the episode, Matt suggested an alternative: the corpse of a dead star. I think Boris Karloff would be an appropriate choice.

[@chipgruver2911]

@@brothermine2292 I think Carl Sagan deserves that honor. Should his ghost decline, then Richard Feynman?

[@brothermine2292]

​@@chipgruver2911 : If you want to honor a star scientist, Bose and Einstein come to mind.

[@JohnOverstreet]

Thank you for helping me understand how superfluids and superconductors are connected.

[@scottslotterbeck3796]

Yeah, surprising to me, I'd never make the connection.

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I have set every channel I'm subscribed to to not notify me when videos are updated specifically because I preferred the email notification system KZbin used to use. How I use KZbin now-a-days is when I am ready to watch videos, I sit down and load my subscription page, NOT the home page.

[@TestECull]

17:24 that's what subscribing does. I don't need my notifications blowing up because every channel puts up a video. And in fact, seeing this video in my sub panel is how I got here in the first place.

[@realityChemist]

Mainly commenting to help out with the algorithm stuff, but if anyone at Spacetime does happen to read this: at lease one regular viewer (who happens to be a materials scientist) would love more episodes on solid state physics! Personally I find the physics behind wave-crystal interaction (e.g. x-ray / electron diffraction) to be fascinating. It's not too hard to understand at a basic level (e.g. Bragg's law), but the physics there are surprisingly deep when you go digging (e.g. crystal momentum, the Laue relations and the Ewald sphere construction, the connection of this whole topic to Fourier transforms, etc...)

[@Juxtaposed1Nmotion]

What is spin glass?

[@alohatraveler]

Excellent content thank you

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This may be the best channel on KZbin. I like how you get someone who clearly is an expert, with content that is kept purposefully at a level more complicated than most people would understand, including myself. Finally a place where the audience are assumed to be smarter and more resourceful rather than the opposite. Not a fan of ads though, e.g. the Brilliant ad in this one. I already pay for KZbin premium.

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Keep the episode references coming Please! It helps to connect this information into trees and fights the neblous nature that this information/discipline can have, helping it to have reference points to attach to for the purposes of remembering and integrating what was learned into a somewhat usable framework where curosity is more easily leveraged. Awesome eqisode and I followed the video references I needed. This is one of my favorite series on the net.

[@kdeuler]

I could swear PVC pipe primer is a superfluid. I've seen that purple stuff flow against gravity and out of the can!

[@RealCrafter645]

That can be caused by surface tension

[@JAYMOAP]

Would be interesting to see an episode on the SYK model and its profound implications to black holes

[@aashilr]

Liking this so PBS can see, even though I have no idea what SYK model is but has something to do with black holes which I find very fascinating :D

[@zilvoxidgod]

Fantastic episode. You're so good at weaving elements together to create a whole picture of a concept.

[@wallacyf]

Fantastic episode! It's amazing how you manage to explain such complex things so well!

[@arnekristian5704]

FOR THE ALGORITHM!

[@slidebleed183]

Sometimes science gives me existential dread

[@PeterGaunt]

Thanks for this! This was a favourite topic amongst the physics pupils in my school when I was 17-18 in the late 1960s. A number of lunch times were spent trying to work out why it wouldn't go on forever. When came to no conclusion as I recall.

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I've been watching since the very beginning and it warms my soul how many episodes there to reference.

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been watching for 2 years

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Been watching for 6

[@rellethias]

Started in 2016 I think?

[@smartball495]

Me also and this channel has easily become one of my favorites

[@nicemandan]

I was lucky enough to see "Marilyn" in action at Manchester university, my friend was using it for his PhD. Got to see how they get things down to near absolute zero with a vortex of helium 4. Was fascinating, someone should do a video on it 😊.

[@sirtrancealot]

Excellent video Matt! This helped me understand the Boson and Fermion relationships as well as the nature of superfluid. Double topics here!

[@Becidgreat]

15:17 man the scale is mind BLOWING! I get this stuff way more than I used to. I think your stuff was over my head before and I wasn’t ready for it. I needed a bigger knowledge base to compare and comprehend. I’m very interested in dark energy and noise disturbances in quantum computing but I know nothing about either.

[@iainmackley]

And now I get why the pauli exclusion principle is a thing! I don't know why the symmetric/antisymmetric difference never clicked before, especially having watched the spin episodes. Thanks Spacetime! Also, question; is Helium-4's boson-like behavior why it is emitted in alpha decay? or is that an unrelated coincidence?

[@falnica]

Excellent question. Yes, alpha decay needs to emit a boson, and it just so happens that two protons or two neutrons would be very unstable, so Helium-4 is the lightest stable boson it can produce, now, if you ask why it has to be a boson... that's a story for another time

[@iainmackley]

@@falnica Thank you! Good old weak force being weird, I'd guess.

[@IamGrimalkin]

​@@falnica Does it have to be a boson? Beta decay, p-drip and n-drip all emit fermions so I can't imagine why that would be the case. I was under the impression helium was emitted because helium-4 is doubly magic (basically, protons and neutrons have 'shells' in a similar way electrons do in an atom, and magic numbers of them are when the shells are full). Other magic-numbered isotopes can also appear in Nuclear fission. I think the reason helium is more common is that fission requires a larger increase in the nucleus' surface area, which requires a lot of energy because the protons/neutrons are attracted to each other.

[@donlevoneshabanov4437]

First comment, I can't believe KZbin gave me such an early notification for my favorite channel. P.s. I accidentally do what you ask in the end 🙂

[@birbdad1842]

And nobody cares if you're first.

[@francaisdeuxbaguetteiii7316]

@@birbdad1842damn bro, “nobody cares” yet you reply to everyone!😂

[@quantumcat7673]

This "perpetual motion" in a superfluid is akin to the rotation of a space object. Both phenomena start with some energy kick and the energy is not dissipating (at least not quickly) in the environment.

[@jimc1327]

Great clarity

[@maddsua]

This is a science lesson I hope people had in schools/universities. Yeah, uni, it's cool that I know how to calculate that, but I'd very much appreciate a bit of visuals and the context

[@martiddy]

People in high school can barely understand basic physics, now imagine how confused they would be if you teach them about quantum physics.

[@maddsua]

@@martiddy well, I sad nothing about the high school. English is weird and I can barely speak it

[@thenovicenovelist]

@@maddsua I think it's because you said "schools/universities" in your original post. In the U.S., we usually think of schools as Elementary, Middle or Junior High, and High Schools. Especially when someone mentions universities separate. There are other types of schools, but they are not as well-known. I'm not sure where you are from or where the other person is from, but I can understand why someone might assume you meant high school.

[@thenovicenovelist]

@@maddsua Also, your English is much better than my ability to speak some of the languages I'm practicing.

[@arga400]

I want an episode on if "Absolute Zero" is theoretically possible. Absolute Zero means no particle has any energy thus they are not moving at all, that would mean we know both the speed and location of an electron, since the speed is 0 and the location is obvious as is not moving.

[@MrWayneDX]

It’s not. We would need an infinite amount of energy to do so which would introduce heat back into the system. I’m almost 100% sure we had him talk about it at some point.

[@Mp57navy]

It's not. At least not in this universe. And you answered your question yourself as to why.

[@siddharthverma1249]

Doesn't that relate to the atomic/molecular motion a.k.a heat and ignores the energy inside individual atoms/molecules perhaps except for spin? Genuinely asking

[@oscaracuellar04]

Short answer, No, for a more awesome and detailed explanation Matt went over it in a previous episode kzbin.info/www/bejne/hafKi6R9ratmm9E

[@d4slaimless]

From thermodynamic point of view reaching zero is impossible because to remove heat you need to transfer it from hotter body to colder one, but you can't get a body with temperature lower then 0. And if cooling agent has a temperature of zero (but you just want to reach it, so where would you get one), then the body being cooled would approach the temperature of the cooling agent asymptotically - means would never reach zero. Also particles in a crystal lattice at 0 K would still have minimum vibrational motion, so I'm not sure you will be able to know both speed and location.

[@SashaRomeroMusic]

Yeah i didn’t see this until today, while I normally see episodes at the top of my feed the day they come out

[@philochristos]

That was really interesting and well-explained. I felt like my understanding grew. I hope I don't forget this.

[@memofromessex]

Man, I got most of that. I'm either a genius or Matt is a genius for explaining it so well!

[@LuisSierra42]

We are definitely not geniuses

[@shamimhussain396]

So, the particles don't interact because that would require exchange of energy and one of them would need to move to a lower energy state. But at this point, there IS no lower energy state! 😅 It all makes perfect sense now. Physics books are like - they occupy same energy state, cannot interact bla bla, but none of them bothered to explain why they cannot interact. 🙃

[@falnica]

The joy of finally understanding

[@ThePowerLover]

@@falnica Almost.

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Props for self-referencing Space Time (the show) where you always reference Space Time (the, well, everything) in your last sentence.

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Another brilliantly explained episode sowing so many concepts. Now friction seems so obvious! Thanks PBS spacetime ❤

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Too bad that teachers in Florida cant show this in schools with the video talking so openly about drag.

[@edmontontech2008]

I love how Anti-symmetric wave functions is phasing and noise cancelation in audio frequencies.

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Its been a hot minute since I’ve watched space time, I Just wanna thank you for reminding me of that feeling of hope and possibility, the one you get in science class when you know you could learn any number of cool new things… when there weren’t big looming awful problems in your life and you could easily immerse yourself in learning and expansion. My fathers very sick and is going on hospice. He’s been battling a rare cancer for 2.5 years now. I’d completely forgotten this feeling. Thank you again for reminding me of what life and living feels like at a time in my life when I’d completely forgotten

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Always love how you end on "...of space time." This one was great! (The science was fascinating as well, as always!)

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the only thing extra i can do besides donating rn to support this channel is posting this commect right. I love supporting PBS and i love supporting this channel.

[@CHUCKLZLORD]

This is a fantastic explanation. Thank you!

[@oliverh.9814]

This is just a phantastic channel. First time I see such a good explanation of superfluidity. Well done Dr. O'Dowd and PBS Space Time

[@pendagar449]

This was a really really good eppisode! I felt that everything was explained perfectly for me to understand and that the goal of this video was to educate me, not get clicks

[@n0e0]

Awesome explanation of spin! Finally.

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Thanks for always enlightening us on the fascinating nature... of space time!

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I'm not a subscriber but YT recommended your video 23 min from publishing (I'm in Portugal, Hello across the pond). You got my view and a like for good measure. The algorithm knows I don't loose 1 episode

[@hoosierdaddy1469]

Thank you for this explanation regarding superfluids! It didn't make sense to me previously.

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This channel is so good. Please never stop making good physics content!

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The new graphics look really good! Love the PBS Spacetime team ❤

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Great discussion!

[@earthrocker4247]

I'm in way over my head, but still watching & learning something I guess. That was a useful visualisation of Bose-Einstein condensate and I'm adding to my knowledge of the attributes of Fermions and Bosons. Cheers. \m/ \m/

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I’m hooked and I always watch the whole thing all the way through first time I see it

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From what I've heard, mixing live streams with recorded content on a channel kills the youtube algorithm. One solution I've heard of is to just hide livestreams or move the livestreams to another channel.

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Hope your channel continues to grow!

[@zacharywong483]

Fantastic video, as always!

[@joansparky4439]

interesting as always, nicely done

[@okman9684]

I watched Spectral 2016 That movie really did a good job in demonstrating the properties of BEC

[@insu_na]

definitely valid, I didn't see the video in my sub box until just now. now that doesn't mean it wasn't there, but I had also refreshed the homepage hundreds of times and not a single time was this video recommended to me, despite being subscribed here (and on patreon)

[@slug..]

These are some of my favorite videos on KZbin

[@SlurpieDoo]

man i love this show. thanks guys ♡

[@silversonic1]

Part of your algorithm issue is actually that you'd been posting on Thursdays and are back to posting on Wednesdays, which can throw a person's expectations if they aren't looking at the subscriptions window to see what's new.

[@Stealth86651]

Thank you so much for the videos, effort and series in general, really appreciate them. I've been having subscriptions not showing up at all with other channels too. It's just youtube doing what they can to promote certain channels over others for whatever reasoning I'd imagine, otherwise they'd be doing something about it.

[@CosmicAliveness]

Absolutely amazing have you been saving this ?

[@starrywizdom]

First found out about some of the weird properties of supercooled Helium when reading an Isaac Asimov article in the 1980's. Very fun to learn about the quantum underpinnings of those properties.

[@WillYouVid]

PBS spacetime team / Matt O'Dowd do such a great job that one can focus, follow through and take up new concepts even when relaxing on the couch after a long day of work

[@MrHandsy]

Wasn't subscribed, but now subscribed. Probably not intelligent enough to understand this, but glad others who are can get this information freely. A beautiful thing.

[@g137hampton]

I really liked the long road you took to end it with "Space Time".

[@paul454]

This is, by far, the best explanation of superfluidity I've seen. Thank you!

[@jo_crespo11235]

Excellent video, keep the hard work,.

[@Psychx_]

I'd love to see a video about Causal Dynamical Triangulation (CDT), Quantum Einstein Theory and other novel approaches to quantum gravity. Thanks for always producing such awesome, informative and entertaining content. Cheers!

[@debrainwasher]

Cooper pairs are really fascinating stuff. On the surface of superconductors as film of a couple of Nanometer thickness, they are able to conduct electricity without resistance and and exert diamagnetic forces (Meissner-Ochsenfeld-effect), with a tremendous specific force carrying capacity. Even more fascinating are Cooper pairs within topological insulators at room temperature (e.g. nano-bismuth with a grain-size below ca. 9nm has a transition temperature of 336.7K) - vulgo «super-insulators». Like semiconductors, they have a band-gap between the valence- and conduction band, but they don't follow the Shockley diode equation. Like an ideal bidirectional Zener-Diode, they are perfect insulators - or conductors within the conduction band.

[@seangeoghegan]

Wow! I hadn't seen the draining of a superfluid through the bottom of an apparently solid container. Thanks! BTW - I have always thought that the liquid to gas transition temperature of helium was 4.2 K. Learning that helium-4 has a phase transition temperature of 5.2 K was news to me - not in my solid state physics memory. Taking the helium cryostat as being at 4.2 K was a log standing shorthand for me.

[@volkhen0]

Great episode! Love the superfluid tea.

[@haydentravis3348]

Please keep up the good work. Thank you.