You can mix 10 marbles until they sort themselves. Why not 100?

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  • Опубліковано 23 тра 2024
  • This is a sequel to my last "ink tube" video, but this time I explain the title of the project, "the entropy of mixing". Entropy is a super weird topic, so I hope this makes sense, and I hope you enjoy!
    Special thanks to my top Patreon supporters!
    birdiesnbritts
    John Sosa Trustham
    Vladimir Shklovsky
    Aloysius Sparglepartz
    Jason Whatley
    Lohann Paterno Coutinho Ferreira
    Jeffrey Mckishen
    nothings
    Eugene Pakhomov
    Glenn Willen
    R520
    Nick F
    Mirko Rener
    Chris Connett
    Tyler Filla
    Miles Freeman
    Benjamin Manns
    MPG
    Seth Reuter
    Danny Thomas
    Toby T
    Lucy Fur
    tiaz
    Bonus thanks to Patreon supporter PJC, who reminded me that "closed" and "isolated" systems are technically very different!
    Media Credits:
    I Dunno by grapes is licensed under a Creative Commons Attribution license (creativecommons.org/licenses/...) ccmixter.org/files/grapes/16626
    Pink Lemonade by Silent Partner is licensed under a Creative Commons license
    0:00 Intro / The arrow of time
    2:52 The second law of thermodynamics
    3:36 Flipping coins
    10:08 Marble tracking analysis
    13:58 Osmosis
    21:31 Microstates, multiplicity, and entropy
    23:49 REVERSE osmosis
  • Наука та технологія

КОМЕНТАРІ • 1,1 тис.

  • @AlphaPhoenixChannel
    @AlphaPhoenixChannel  19 днів тому +139

    Corrections and FAQ in this comment!
    0) If you want to see the ink machine ideo about turbulent and laminar flow in a tube: ua-cam.com/video/qm5AHAb0SmY/v-deo.html and if you just want to watch it go, I have a 45 minute single cut: ua-cam.com/video/DtYVYfOvgKE/v-deo.html
    1) I'm a little loose with the definitions when I get to the interchangeability of entropy and energy, but that's because it gets really complicated in a hurry - maybe a topic for a future video. What I'm referring to is "thermodynamic free energy", which is not conserved like "real" energy. If you have a bucket of water on a ladder and you let the water pour out of it into a bathtub, you could extract energy from that process with a paddlewheel or something - that's "free energy" being spent. Once the water lands in the bathtub, the kinetic energy of it falling goes into heating the water, so now the energy of the water is in heat, and there's nowhere to put the waterwheel, so the energy, although it's still there, is kinda useless. Entropy is exchangeable with "thermodynamic free energy", not "real energy".
    2) 5:05 "proobability"
    3) When talking about osmosis, I intentionally swept enthalpy of mixing under the rug. there are other (real, non-entropic) forces that can increase osmotic pressure in certain cases en.wikipedia.org/wiki/Enthalpy_of_mixing
    4) my “push the marbles to one side” demo may LOOK like the classic “maxwell’s demon” hypothetical, but it’s supposed to represent what’s actually happening near a REAL semi-permeable membrane. I think the ideal “demon” would not produce osmotic pressure, but even in this demo of 20 marbles, there was some measurable osmotic pressure
    5)

    • @i_am_lambda
      @i_am_lambda 19 днів тому +5

      The initial example of the marbles assumes a perfectly elastic collision. In real life some of the kinetic energy at the initial conditions is permanently lost to heat, sound, deformation etc

    • @kellymoses8566
      @kellymoses8566 19 днів тому +6

      @@i_am_lambda That isn't really relevant to the entropy

    • @i_am_lambda
      @i_am_lambda 19 днів тому

      It is insomuchas the reverse clock could theoretically cool and undeform the marbles and fully absorb the sound waves. It's highly unlikely to happen because this would reduce entropy

    • @renedekker9806
      @renedekker9806 19 днів тому +3

      But "real" energy is conserved in the process, right? Does that mean that, during the osmosis when the sugar water is being pushed up, the fluid cools down? If not, where does the energy come from?

    • @mph8759
      @mph8759 19 днів тому

      And with that, wouldn’t entropy be the “useless” part of the energy, i.e. the less “free energy” (as a proportion of total energy in a system) the higher the entropy of that system?

  • @dejaphoenix
    @dejaphoenix 19 днів тому +2040

    Matt Parker would have filmed coin flip attempts until he got 10 tails in a row, then just casually throw the footage in without further comment.

    • @pitri_hub
      @pitri_hub 19 днів тому +184

      He already did that, in his "10 coin flips in a row" video, with the small modification of letting the first two throws dictate the pattern he's going to go with (effectively reducing this to a problem of 8 coin flips). Whatever arrangement of HHHH..., TTTT..., HTHT... or THTH... he got, he just ran with.

    • @AarushA.S
      @AarushA.S 19 днів тому +2

      Ya

    • @AlucardNoir
      @AlucardNoir 19 днів тому +154

      Yeah, but he's a mathematician, they're not the most mentally sound of people.

    • @CR0SBO
      @CR0SBO 19 днів тому +92

      ​@@AlucardNoirHe's "Parker Sane"

    • @ferretlord3990
      @ferretlord3990 19 днів тому +22

      @@AlucardNoiras a math guy I 111% agree 😂

  • @absolutechaos13
    @absolutechaos13 17 днів тому +432

    The three laws of thermodynamics:
    1. You can't win.
    2. You can't break even.
    3. You can't even quit the game.

    • @iammeok
      @iammeok 14 днів тому +39

      Worst casino in history smh

    • @janoycresva9941
      @janoycresva9941 13 днів тому +71

      Get it twisted, you will win, you will break even, 99% of gamblers quit before their cup of cold coffee spontaneously becomes warm

    • @willmcclard206
      @willmcclard206 12 днів тому +5

      @janoycresva9941 i think it’s a little more than 99%😉

    • @eldersedai870
      @eldersedai870 12 днів тому +10

      I lost the game

    • @johnjameson6751
      @johnjameson6751 10 днів тому +24

      There is version of this that actually helps to remember the physics as well as being funny:
      1. You can never win, you can only break even.
      2. You can only break even at absolute zero.
      3. You can never reach absolute zero.

  • @chachopaul695
    @chachopaul695 19 днів тому +424

    I like to use this example when someone says “well it’s possible.” For an extremely extremely unlikely event.
    “Yes, it is possible, it is also possible for every molecule of oxygen in the room to shift up 6 feet, but I’m not about to spend my whole life standing on chairs to avoid suffocating.”

    • @NaridaX
      @NaridaX 18 днів тому +100

      They might shift down instead, after all.

    • @pierrotA
      @pierrotA 18 днів тому +41

      I like to say that it is possible to pass through walls.
      Particules do teleport with the tunnel effect, you just need to have all your particules teleporting at the same time, in the same direction, for the same distance.

    • @yschroder
      @yschroder 18 днів тому +26

      My dad always says: I won 6 bucks in the lottery. I did not play.

    • @400_billion_suns
      @400_billion_suns 18 днів тому +13

      @@NaridaXGet low, get lowww, to the window, to the wall, til en-tro-py makes us crawl

    • @vaderdudenator1
      @vaderdudenator1 16 днів тому

      Stealing that

  • @msachin4885
    @msachin4885 19 днів тому +883

    As a Physics TA this is absolutely GOD tier Physics education. You've perfectly communicated the basics of undergrad-level Statistical mechanics and Thermodynamics and given a solid foundation for the rest of the math and equations without using ANY Jargon. Like Einstein said, if you cant teach it to a 6 year old you don't understand it well enough.

    • @AlphaPhoenixChannel
      @AlphaPhoenixChannel  19 днів тому +141

      haha thanks! I did also take graduate thermodynamics for a few classes but I can’t claim to remember any of it… way too abstract. Base level statmech is just so wonderfull because it’s just probabilities.
      (I actually took thermo from the engineering dept. and the physics dept. in adjacent semesters in undergrad. the MSE side was like "hey here's an equation for the Gibbs, go use it, and the physics side was like "go count dots in boxes" and see what happens. I liked the physics one more. Thanks Dr. Daniels!

    • @idontwantahandlethough
      @idontwantahandlethough 18 днів тому +32

      Einstein obviously didn't have kids when he said that.. six year olds listening is highly contingent upon snacks, naps, and other more mysterious factors we can't possibly fathom. You can do EVERYTHING right and that kid may very well be like "vroom vroom, rocket go fast!"

    • @Horse-ic9ym
      @Horse-ic9ym 18 днів тому +5

      ​@@AlphaPhoenixChannel thanks for showing me a physical not reversed video showing of kinda like bogosort.

    • @NoName-zn1sb
      @NoName-zn1sb 17 днів тому +2

      you can't

    • @LifeInJambles
      @LifeInJambles 13 днів тому +6

      @@idontwantahandlethough "if you can't teach it to a 6-year-old who is currently curious about specifically this"
      That's one of the things my mom taught me about parenting that's proven pretty useful already and my kids are only two: you might be able to get them interested in what you wanna teach them or what you want them to do... but you'll never make them pay attention or learn things they're not interested in. That's just how the human brain works, and small children are even less capable than most of us of self-regulating their focus.
      Okay, to be fair that's me extrapolating what my mom taught me to make it fit what we're talking about in a little more useful way. What my mom taught me is "When they ask the question is when they'll learn it. You can't set it aside for later and expect them to care." and that's apparently why she ended up explaining sex to my brother in the middle of a crowded public bus.... cause that's when he asked about it, and she figured it was important he understand it. Absolute legend of a woman; lifelong inspiration to be sure.

  • @vesae2676
    @vesae2676 19 днів тому +224

    So you're telling me there *is* a chance?

    • @AarushA.S
      @AarushA.S 19 днів тому +6

      Yes

    • @backwashjoe7864
      @backwashjoe7864 18 днів тому +9

      "I get that reference!" :)

    • @Nixderg
      @Nixderg 18 днів тому

      No. Statistics is a scam created by the shadow government.

    • @LuisSierra42
      @LuisSierra42 16 днів тому +7

      Smart & Smarter

    • @mikeymike437
      @mikeymike437 15 днів тому +6

      Ms. "Samsonite" 😉

  • @cornoc
    @cornoc 18 днів тому +54

    There is a consequence of entropy we deal with in our day-to-day lives at the macroscopic level: tangled wires. There are so many configurations where wires are tangled compared to the few configurations where they're neatly separated that they have a tendency to become tangled with the energy input from random jostling.

    • @jamesgebhardt6175
      @jamesgebhardt6175 18 днів тому +12

      You can do a kind of reverse osmosis on them too, usually. Grab two tangled bits, apply tension (analogous to pressurizing the filter) and jiggle them around (analogous to increasing the temperature). Make entropy work for you, instead of the other way around.

    • @periodictable118
      @periodictable118 18 днів тому

      @@jamesgebhardt6175 but making entropy work for you requires energy, meaning at the end of the day, you are still working for entropy. Entropy is like a loan shark that gives you work but at an exorbitant interest rate

  • @ecophreak1
    @ecophreak1 19 днів тому +189

    As a biologist I'd never really looked in to why osmosis happens just knew that if different concentrations of fluids are separated by semi permeable membranes it occurs, thanks for showing me why

    • @alveolate
      @alveolate 18 днів тому +2

      when life (aka cells) look like they're "cheating" entropy, isn't it just using osmosis + some energy? that seems true at least at the cellular level right?

    • @mandrakejake
      @mandrakejake 18 днів тому +3

      Are you aware of Maxwell's Demon? It's a thought experiment based on this sort of scenario

    • @SojournerDidimus
      @SojournerDidimus 18 днів тому +8

      ​@@alveolateYes and no. Yes, cells use osmosis to a great extent. No, cells use "pumps" to actively work against entropy and osmotic balance. The most well known in high school text books is one that pumps sodium and potassium to different sides of the synapse membrane so they can be reused as neurotransmitter.

    • @Eagle3302PL
      @Eagle3302PL 18 днів тому

      @@SojournerDidimus I thought electromagnetism is involved too, no? Like salty water is charged differently than non salty water so that can create some work too.

    • @lasagnahog7695
      @lasagnahog7695 18 днів тому

      I get very excited when biology and physics explicitly overlap.

  • @matthieupique209
    @matthieupique209 18 днів тому +101

    Dude is actually Maxwell's demon with balls.

  • @BloodyMobile
    @BloodyMobile 19 днів тому +99

    12:30 this is a great visualization why it's /theoretically/ possible to throw a tennisball at a brickwall and have it quantum tunnel through.
    But the /chance/ that every single particle of the ball dodges every single particle of the wall in it's path is less likely than the ink reversing out of it's "spike".
    14:30 I was already wondering why osmosis filtering requires pressure to work. Now I know. Because without the pressure, the water would "prefer" to become dirtier instead of cleaner.

    • @Henrix1998
      @Henrix1998 19 днів тому +2

      I ran into this topic couple days ago and apparently that theory is abandoned and more "advanced" quantum theories are used

    • @annoloki
      @annoloki 19 днів тому +1

      Nah. There are forces holding the ball together, so the ball would never pass through the wall... you could argue maybe that it would integrate into the wall, but not pass through. Like a fishing net passing through another fishing net.

    • @mina86
      @mina86 19 днів тому +4

      They way I think about it is that the dirty water wants to become cleaner (i.e. wants the concentration of impurities to be lower) by pulling in the clean water.

    • @DanKaschel
      @DanKaschel 18 днів тому +1

      @@mina86 The molecules are moving around more or less randomly. So if there is a greater concentration of something on one side of some arbitrary boundary and one particle from each side swaps places, the "dirty" side had a higher likelihood of sending a "dirty" particle than the clean side just by virtue of there being more. This probability imbalance means that every interaction works to reduce the gradient.
      Imagine a 10x10 grid where the 10 cells on the right edge are black and the rest are white. Every second, for every pair of adjacent columns, a random cell on the right will swap places with a random cell on the left.
      On the first swap for the last two columns, the last column MUST send a black cell because it only has black cells. More swaps between those columns will equalize the number of black/white cells until the probability of sending a black cell is equal on both sides. Since all column pairs are swapping, this will result in a gradual migration of the 10 black cells until they are roughly equally distributed.
      So if you had to assign "desire", you'd have to say that the "dirt" in the water wants to go where there is less dirt, while the pure water wants to go where there is less pure water.

    • @mina86
      @mina86 18 днів тому

      ​@@DanKaschel, there is a membrane which doesn’t allow ‘dirt’ to pass through.

  • @brandy1011
    @brandy1011 19 днів тому +109

    I LOVE the overall explanation, but I have a little nitpick about the sugar/water example: At sufficiently high sugar concentrations, statistics is not the only force driving the dilution, but energy (mixing enthalpy) will be released by changing the intermolecular interactions between sugar and water (there will be "free" water instead of only "hydration shell" water touching other "hydration shell" water).
    By chance we actually produced a physically-chemically better, albeit less tangible, example, when decommissioning an NMR magnet a few months ago: We closed the helium pressure sensing line at the magnet cryostat, but left the pressure sensor at the other end connected. Because the line (plastic hose) was more permeable to helium than to air (as most things tend to be), the pressure inside the hose actually decreased by some 200 mbar below ambient pressure over a few weeks. Helium diffusion from the inside to the outside was more likely than the other way round due to the concentration gradient, and air diffusion in the other direction was hindered by the material of the hose. However, there are no relevant interactions between the different gases that would contribute to this, at least not at the pressures and temperatures we are talking here.

    • @bosstowndynamics5488
      @bosstowndynamics5488 18 днів тому +23

      There's a similar example to this on Cody'sLab, Cody filled a set of balloons with different gases and the balloons with heavy gases that diffuse poorly through latex actually self inflated a bit by absorbing air

  • @Shatdoox
    @Shatdoox 19 днів тому +83

    This made me think of another way of explaining why a systems entropy increases with the coinflips :
    If you have a random system of coins, lets say 6 head and 4 tails, and you have to randomly pick one coin to flip, you are more likely to pick a coin showing head since there are more of them, then when you flip that coin, you can either land on head and nothing changes, or land on tails and entropy increases. This makes it clear why any system tends to entropy.
    In your example at 9:16 you flip all the coins at once instead of picking one at random to flip which made it less clear to me why it would tend to increased entropy.
    Thanks for another great video :)

    • @AlphaPhoenixChannel
      @AlphaPhoenixChannel  19 днів тому +21

      Of the coins that weren’t “excess” heads or tails, the expectation value is still 50:50

  • @jhacklack
    @jhacklack 19 днів тому +180

    I guess a non circular way of phrasing the second law is "physical distributions of things will resemble statistical distributions, and those distributions get narrow if you have enough things"

    • @bosstowndynamics5488
      @bosstowndynamics5488 18 днів тому +8

      That still winds up circular though, because the human bias is also the reason those statistical distributions occur, our tendency to consider 9 heads plus one tail to be the same thing as 4 heads, one tail then 5 heads.

    • @idontwantahandlethough
      @idontwantahandlethough 18 днів тому +12

      @@bosstowndynamics5488 oh god, it's circles all the way down. I'M SPIRALING!
      *SPIRALING!*

    • @lvlinty
      @lvlinty 18 днів тому

      ​@@bosstowndynamics5488that's just combinatorial probability.

    • @bosstowndynamics5488
      @bosstowndynamics5488 18 днів тому +3

      @@lvlinty Yes, but the choice to combine some outcomes and consider them the same is still a choice humans made when developing these concepts

    • @KingofJ95
      @KingofJ95 18 днів тому

      ​@bosstowndynamics5488 Except we made those choices because they match what we see in reality and because considering every single coin flip that has ever happened is ridiculous.

  • @LiborTinka
    @LiborTinka 19 днів тому +31

    This is why production of industrial chemicals often runs at high temperatures and pressures, often in a gas phase. It's basically to beat unfavorable chemical equilibria... Sometimes heat is used just to speed things up if the product formation is thermodynamically favourable but kinetically unfavourable. The product is often continually separated from the reaction mixture to keep its concentration low which favors more production as the system continually approaches chemical equilibrium.
    One of the oldest of such processes is the production of quicklime in a lime kiln. Here calcium carbonate is roasted at high temperatures give off carbon dioxide, leaving behind highly reactive calcium oxide melt used for making cements. The quicklime "wants" to turn back into calcium hydroxide or carbonate once it cools down, because different conditions favor different products. This is why it's so hard to make pure chemicals, especially organics - sometimes it's super tricky to separate a single compound and this explains why 98% purity costs $10, 99.9% purity costs $100 and 99.99% purity costs $10,000+

    • @zanicar4087
      @zanicar4087 18 днів тому

      Biogenesis, evolution... !?

    • @RossReedstrom
      @RossReedstrom 18 днів тому +2

      Much of practical bench biochemistry is learning ways to separate mixtures of biomolecules without destroying the molecules you want to study.

    • @nasonguy
      @nasonguy 13 днів тому +1

      @@zanicar4087 Is that a question?

    • @Liliphant_
      @Liliphant_ 9 днів тому +1

      so this is what made walter white's meth so special

  • @AnarchoAmericium
    @AnarchoAmericium 19 днів тому +30

    Here's an interesting fact: a microstate is mathematically identical to a function, and the collection of all possible microstates is the same thing as a function set.
    So the configuration of a system with n-many particles where each particles can be in one of m-many states is mathematically equivalent to a function f:n→m. There are exactly m^n possible functions/microstates.

  • @smor729
    @smor729 18 днів тому +49

    This is so cool, I have never really considered that "entropy always increases" is not as much a physical law as just a restatement of the law of large numbers in an unbounded universe.

    • @denelson83
      @denelson83 15 днів тому

      Except the universe does not have an infinite amount of energy.

    • @rr.studios
      @rr.studios 15 днів тому

      ​@@denelson83How do you know that?

    • @denelson83
      @denelson83 15 днів тому

      @@rr.studios Because if it did, the Universe would not have started with a Big Bang, but would have only existed for less than a picosecond before becoming a black hole.

    • @rr.studios
      @rr.studios 15 днів тому

      @@denelson83 Is that an assumption you've made based on studying other celestial bodies or are you a physicist? That kind of sounds like the process of how black holes are thought to come into existence.

    • @denelson83
      @denelson83 15 днів тому +3

      @@rr.studios Well... It seems there is no scientific consensus on whether or not the universe has infinite energy.

  • @pyglik2296
    @pyglik2296 19 днів тому +65

    12:10 Nice to see "10 billion human second century" as a unit :)

  • @Splarkszter
    @Splarkszter 19 днів тому +69

    Oh cool. So "Do you know why is it hard for things to be 'in order'? It's not because it's hard, it's actually because it's very improbable!"

    • @Splarkszter
      @Splarkszter 19 днів тому +5

      There are way more instances of disorder than of order. The fact that we exist, we are so improbable that we must be unique!

    • @ChrispyNut
      @ChrispyNut 19 днів тому +1

      UA-cam says no.
      UA-cam's saying your reply to yourself came before the post you replied to (59 minutes ago for the OP, 1 hour ago for the reply).
      Sure, it's different, but if YT allows effect to occur before its cause, it can do all sorts of things.

    • @Jehty21
      @Jehty21 19 днів тому +6

      @@Splarkszter but what makes you say that the way we are is "order"?
      Wouldn't it be much more likely that the way we are is disorder? (we are not 10 heads, but instead 5 heads and 5 tails?)

    • @Eic17H
      @Eic17H 19 днів тому +4

      @@Jehty21 I'm pretty sure we're 1 head and 4 limbs

    • @nzuckman
      @nzuckman 19 днів тому +4

      @@Splarkszter vortices in turbulence are structured, but they stir up the fluid surrounding them a lot so they can happen spontaneously. Life is also a structure that increases the entropy of its surroundings. The fact that life exists is not improbable, it's inevitable! :)

  • @NolieRavioli
    @NolieRavioli 18 днів тому +110

    i feel like alpha phoenix has gone from "applied science" channel to a more "steve mould" type explainer. im here for it

    • @TheMetalButcher
      @TheMetalButcher 13 днів тому +2

      Applied Science > Steve Mould

    • @NolieRavioli
      @NolieRavioli 13 днів тому

      @@TheMetalButcher hmmmmm you make an excellent point sir

    • @NolieRavioli
      @NolieRavioli 13 днів тому +2

      @@TheMetalButcher applied science dont do kiwico crates

  • @VAXHeadroom
    @VAXHeadroom 19 днів тому +23

    5:30 I love that you KNOW there are thermodynamicists watching...

    • @Trenz0
      @Trenz0 17 днів тому +3

      Huh, that's a word?

    • @minerharry
      @minerharry 8 днів тому

      It’s me :)

  • @dawsonhampton5949
    @dawsonhampton5949 19 днів тому +17

    Thank you for explaining this! Everyone has always explained entropy to me as a definite thing not a statistical thing. They always said "Your laundry will never be perfectly folded after a trip through the dryer" when it is *possible*, but just insanely unlikely. Your explanation actually makes sense!

    • @mitchjohnson4714
      @mitchjohnson4714 11 днів тому +1

      Yeah, it's frustrating that I had a couple degrees in engineering and still didn't understand this. I had to think about it on my own for a while before I understood. I believe it was always explained to me very poorly.

  • @stephenjmatthews
    @stephenjmatthews 16 днів тому +7

    As a high school physics teacher I am often frustrated by poor explanations or loose definitions of entropy. This is outstanding! You have explained it in a way that non-physics students can understand. This is extremely helpful for understanding biological systems, heat transfer and the universe in general.

  • @JWC249
    @JWC249 19 днів тому +91

    This guy is like a less evil version of Veritasium.
    To be clear, I'm not implying Veritasium is evil, I'm just taking a 50/50% chance this guy's less evil, and when it comes to making defamatory statements, I like those odds.

    • @Tibyon
      @Tibyon 19 днів тому

      Veritasium is extremely evil

    • @stickyfox
      @stickyfox 19 днів тому +14

      All these YTers giving everyone free science educations online are doing good work.. but they all generally fail to disclose that they're sharing knowledge right out of the textbook and not actually *discovering* anything. I wish they'd share some citations at the end of the videos like the professors do.

    • @Paul_Bedford
      @Paul_Bedford 19 днів тому +21

      With Veritasium, I say it is a higher than 50/50 chance because Veritasium uses science to flex his smarts and learning happening is a side effect

    • @EliasKaydanius
      @EliasKaydanius 19 днів тому +26

      ​@@Paul_Bedfordyeah, I kind of soured on Veritasium with the whole "switch, light bulb a meter away, and light-second long wire" thing. Incidentally, that is also how I discovered THIS channel. Which I like much more.

    • @thecarwasherofshangri-la
      @thecarwasherofshangri-la 19 днів тому

      The Man Who Accidentally Killed The Most People In History. Yeah, "Accidentally"

  • @IdiocracyIsAProphecy
    @IdiocracyIsAProphecy 16 днів тому +53

    wait. you're not styropyro

    • @calabrais
      @calabrais 15 днів тому +10

      Pretty cool, right?

  • @zekanner
    @zekanner 18 днів тому +7

    Perfect timing! Our undergraduate thermodynamics final exam is tomorrow, and I just shared this to channel on our student discord. Already helped a couple people remember how entropy works.

    • @AlphaPhoenixChannel
      @AlphaPhoenixChannel  18 днів тому +7

      That’s great! Apparently I just missed someone else’s exam last week…
      I did sit down like a month or two ago while writing this script and try to rederive the entropy of mixing from n choose k and stirlings approximation, but nothing lined up and I never actually found my mistakes… turns out I did remember the correct starting point but I’ve lost the ability to do the math - good luck tomorrow!

    • @zekanner
      @zekanner 18 днів тому +3

      @@AlphaPhoenixChannel I'm fairly certain we actually did that derivation during an early homework or lecture, but honestly probably couldn't do it off the top of my head rn, and I'm still in the course! So don't worry about it. And thanks! I'm pretty confident, thankfully, it's my quantum 2 and E&M2 exams I'm worried about. 😅

  • @alfredodlp7131
    @alfredodlp7131 19 днів тому +4

    By far the best video for understanding entropy from scratch that I've ever seen. I had a lot of these thought experiments bouncing around in my mind for years. Awesome to see them manifest in a video that's so well made and intuitive.

  • @mikefochtman7164
    @mikefochtman7164 19 днів тому +7

    Love the discussion with the osmotic membrane. This helps explain 'reverse osmosis' desalination plants. It takes high pressure pumps to 'push' seawater against the membranes to get freshwater on the other side. Without the external source of pressure, we wouldn't get nearly as much freshwater because it 'wants' to go dissolve back into the seawater side.
    (edit: wrote this before the end of the video where you explain just this. I guess I jumped to this conclusion from the first part of the video)

    • @Appletank8
      @Appletank8 18 днів тому

      I believe this is also the same forces that cause excess salt in our diet to be fatal, salt water pulls the water out of our cells and destroys them.

  • @askemervigbahnson333
    @askemervigbahnson333 5 днів тому +2

    Veritasium level explaining + >steve mould level demonstrating. Very well done, immediately saved to my physics playlist!

  • @allank8497
    @allank8497 19 днів тому +3

    This is legitimately like one of the best educational UA-cam videos I’ve seen in my entire life (and I’ve seen a lot). Hats off to you for explaining so so well and so thoroughly.

  • @AwestrikeFearofGods
    @AwestrikeFearofGods 19 днів тому +6

    DNA is an entropy reducing device, but it requires energy to do so. Animals eat living things, so they first increase entropy before decreasing it. Plants get energy from the sun as its entropy increases via nuclear fusion.

    • @ExylonBotOfficial
      @ExylonBotOfficial 19 днів тому +6

      Life doesn't actually reduce entropy, it increases the overall entropy in order to decrease entropy in a smaller environment

    • @AwestrikeFearofGods
      @AwestrikeFearofGods 19 днів тому +5

      @@ExylonBotOfficial True. To be precise it's a "local-entropy reducing device".

    • @Orandu
      @Orandu 18 днів тому +1

      That’s why you get more calories per acre farming vegetables than raising animals for meat.

    • @AwestrikeFearofGods
      @AwestrikeFearofGods 18 днів тому

      @@litigioussociety4249 Clearly, I was describing the sun's entropy increasing by nuclear fusion, not the plant. However indirectly, nuclear fusion powers photosynthesis.

  • @illicitsolitude7727
    @illicitsolitude7727 14 днів тому +1

    While i learned about entropy at university, I really appretiate the effort you put into these low-level, tangable examples and models! The time you put into making sure that this concept of entropy is well explained for nearly everybody to understand is astonishing!
    Love your work, keep on doing great stuff!

  • @waffling0
    @waffling0 18 днів тому +2

    In my opinion this is the best science channel on youtube. Consistent quality, with great demonstrations and approachable explanations!

  • @mcpr5971
    @mcpr5971 19 днів тому +4

    It may be useful to compare extreme improbably to other things that we're familiar with: getting struck by lightning 3 times the same day, earth being hit by a devastating meteor, etc. At some point, it becomes much more likely that earth will end than a fluid and ink arranging to spell your name.

  • @bignerd3783
    @bignerd3783 17 днів тому +4

    maxwell's demon casually boiling me using a door

  • @FranzBiscuit
    @FranzBiscuit 18 днів тому +2

    Another aspect of entropy WRT to the current state of the universe which is often glossed over: Take a pebble being dropped into a body of water, for example. The reason why you never see a stone being randomly spit out of a lake is not merely due to the fact that such a thing would be "unlikely", but quite simply because gravity cannot be reversed! And it is worth mentioning, because a lot of people seem to think time reversal to be a "fairly trivial" affair. Which is of course rather irritating, considering that it is in fact not.
    Great video, by the way! I love these kinds of deep-dives into the world of physics.

  • @kiksu1
    @kiksu1 18 днів тому +1

    This is absolutely the best explanation and demonstration of entropy I've ever seen! Thank you! ❤

  • @Splarkszter
    @Splarkszter 19 днів тому +4

    Thank you for making such high quality awesome entertaining educational content.

  • @PushyPawn
    @PushyPawn 18 днів тому +4

    For a split second ALL the air molecules in my room gathered in one corner and my head 🤯..

    • @nasonguy
      @nasonguy 13 днів тому +1

      Boltzman has left the chat.

  • @AJ5
    @AJ5 17 днів тому

    Watching you is the best thing that I have going for me in my life right now.
    Thanks for sharing your work!

  • @bluwaffle966
    @bluwaffle966 19 днів тому +1

    Absolute banger, your intelligence and passion is on full display, again. Award worthy content.

  • @Marco-xz7rf
    @Marco-xz7rf 19 днів тому +7

    shuffle sort, once quantum computers work, we can basically sort anything in one iteration, by having "unlimited" shuffles at the same time and one of them will be sorted after :D

  • @scottpageusmc
    @scottpageusmc 18 днів тому +3

    I'm a former Turbofan Test Engineer for Lockheed and Rolls-Royce at Stennis Space Center from 2007-2012.
    I've also been programming since 1986 and put that to good use for Rolls-Royce by developing a "test cell simulator", which simulated the testing of a Trent 900, 1000, and XWB jet engine from our control room perspective.
    In order to accomplish that, I had to simulate the jet using dozens of polynomials to replicate the brayton cycle. That includes entropy and entropy of each blade in the compressor and turbine stages, while being based on rotation velocity.
    Anyway, your videos remind me of those days and thanks for doing this!

  • @alvinmoore308
    @alvinmoore308 13 днів тому

    Well done, great video! One of the best I have seen on entropy, and really shows the statistical nature of it - that as the number of particles increases, the likelihood of them all separating out on their own quickly gets very close to zero. Not zero, it COULD happen, but it just never will. This just reminded me of the infinite improbability drive in Hitchhiker’s guide to the galaxy. In that book, you had the room full of monkeys at typewriters who came up with the complete works of Shakespeare. Again, great job!

  • @keenheat3335
    @keenheat3335 18 днів тому +2

    the reverse implication is also true though, the smaller the system, the more likely you going to get "ordered" outcome. theoretically if a hypothetical spatial divider were to subdivide the state space into many sub space, you get more reversal.

  • @Trainwreck1123
    @Trainwreck1123 19 днів тому +4

    PBS Spacetime has a great episode (I think? I don't remember exactly where I heard this actually) where they posit that life is purely a consequence of the Universe's march towards higher entropy. Life's "purpose" is basically just to increase entropy if you look far enough down; all we really are is walking chemical reactions, and in the case of intelligent life it's even more true because we consume at a greater rate than life would otherwise.
    By this line of thinking it is essentially guaranteed that more intelligent life exists, isn't it?

    • @averteddisasterbarely2339
      @averteddisasterbarely2339 18 днів тому

      Imagine what technology exists out there given that space and time are both never ending ! It's hard to except or conceive that there is life trillions of light years away from us

  • @IzimDev
    @IzimDev 19 днів тому +3

    first 🎉🎉 btw, I love your videos ❤

  • @johnreiland9180
    @johnreiland9180 18 днів тому

    Every time I see a new video on this channel I'm more and more convinced that I'm watching a future star in the realm of popular science. Keep giving your videos the same amount of care you're giving them here, and success will be beating down your door.

  • @theultimatereductionist7592
    @theultimatereductionist7592 18 днів тому +1

    Ignore Boltzmann's Constant. Fact: the sum of p(k)*ln(1/p(k)) over N microstates indexed by k is maximized when all p(k) are the same, and thus equal 1/N. Then the entropy (modulo B's constant) is ln(N). Made a quick program in Mathematica to calculate entropy for a biased coin with probabilities p and q.
    Entropy is maximized at p=q=1/2. But it is unbounded with n= number of coin flips.
    n = 33;
    p = 0.75;
    q = 1 - p;
    Sum[Binomial[n, k]*(p^k)*(q^(n - k)), {k, 0, n}];
    s1 = Sum[k*Binomial[n, k]*(p^k)*(q^(n - k))*Log[p], {k, 0, n}];
    s2 = Sum[(n - k)*Binomial[n, k]*(p^k)*(q^(n - k))*Log[q], {k, 0, n}];
    s3 = -(s1 + s2)
    // returns 18.5571
    n=49, p=0.75 returns 27.5544
    As n increases without bound, so does the entropy. But for any n, the return is 0 when either p=0 or 1.

  • @flyviawall4053
    @flyviawall4053 7 днів тому +3

    I don’t think this explains why and what direction time flowing. I once said a white hole(time reversed black hole) is not white, because light is coming out from eyes back to the white hole. It doesn’t even have colour. Same can apply to your idea, still nothing restricting time to go backwards.

  • @andynz7
    @andynz7 18 днів тому +1

    I thought I had a pretty solid grasp on basic thermodynamics and entropy from university-level chemistry, but your explanation and demonstrations take it to a whole new level!

  • @Merkw
    @Merkw 14 днів тому

    The only video I've seen in the whole UA-cam that talks correctly and without unnecessary bells and whistles about entropy. Congratulations

  • @Masonova1
    @Masonova1 18 днів тому

    THE single best concrete explanation of entropy I've ever seen, hands down. Thanks!

  • @amiralozse1781
    @amiralozse1781 17 днів тому +1

    your explanations and examples are extremely well done and thought through - AWESOME!!

  • @5eurosenelsuelo
    @5eurosenelsuelo 2 дні тому

    I appreciated it the final connection between entropy and energy. I didn't see that crucial step in other similar videos. I'll have to watch this one again a few times until I really understand everything that's going on.

  • @davestorm6718
    @davestorm6718 12 днів тому

    This is the best demonstration and explanation of entropy I've ever seen. Thanks!

  • @Noone-lw6ge
    @Noone-lw6ge 17 днів тому

    Congratualitions for the great video, it's one of the best explanations on entropy I've ever seen.

  • @larswillems9886
    @larswillems9886 16 днів тому

    This is the best video on entropy that I have ever seen! It was a joy to watch

  • @valeriooddone
    @valeriooddone 11 днів тому

    The best explanation of entropy I have ever seen. Thank you!!

  • @haaspaas2
    @haaspaas2 19 днів тому

    Very intuitive and thought provoking explanation. Thanks for the video!

  • @levoniust
    @levoniust 18 днів тому

    This is the most unique way I've ever seen entropy explained. And I love it!

  • @Mr_Wiley
    @Mr_Wiley 7 днів тому +2

    Imagine the ink in the water system shot out and the ink cloud spelled out *“Entropy, pfft”* and then dissipated- but the camera broke.

  • @gabe2237
    @gabe2237 18 днів тому

    Your channel is awesome. Every video is really intuitive. If only this video had come out before my thermodynamics final last week 😂

  • @GBart
    @GBart 18 днів тому

    Goddamn I love your channel!! This is the best demonstration of entropy I've ever seen

  • @joeisuzu2519
    @joeisuzu2519 11 днів тому

    Awesome work. Thank you for the lesson. It has taken me many years to understand entropy. Excellent methodology to expose nature of entropy. Well done

  • @friparvus
    @friparvus 12 днів тому

    As always, such a great video!

  • @rkond
    @rkond 18 днів тому +2

    I like the video. You managed to find a sweet spot with not too much oversimplification. Maybe you can do a follow up on how temperature can actually be defined from the entropy and how system with a negative absolute temperature like a laser is effectively hotter than any positive temperature system.
    Also the entropy being a logarithm makes it additive when two systems are joined but the multiplicity of the combined system is a product of multiplicities of its parts. That makes it very clear as to why the logarithm.

  • @davidabner8885
    @davidabner8885 18 днів тому +2

    This is the best video I've ever seen on entropy

  • @sipsun8
    @sipsun8 19 днів тому

    Very interesting! Thank you so much, Brian! A big hug. Luca 😊

  • @Lampe2020
    @Lampe2020 17 днів тому +1

    How fitting that this video came out exactly while I have entropy and all things around it in school XD

  • @JakeSeeber
    @JakeSeeber 18 днів тому

    Wow, this video is amazing. Thank you so much!

  • @nicolosicca7571
    @nicolosicca7571 19 днів тому

    I want u as a professor, i absolutely love this kind of videos and the way u can go Deep with thinghs explaining the Essence of all

  • @newtonbomb
    @newtonbomb 15 днів тому +1

    Great explanation, like usual. This ties into the feasibility and promise of high entropy alloys of 5 or more equi-molar elemental constituents (affectionately called chaos alloys).
    With enough heat and time in the right closed environment during smelting/forging and subsequent cooling, quenching, and tempering procedures, you are almost guaranteed to be able to predict with high probability the possibility of some sort of stable metallic crystal or amorphic structure at room temperature from basic information of the target constituents off the periodic table and some surprisingly simple formulas and macroscopic intuitions. And although you'll never be able to even remotely predict the exact properties of the resulting alloy without an expensive amount of compute because of the computational irreducibility of the massive entropy, with some careful consideration you can nudge the phase space of possibilities to at least narrow a bit in on some pretty exciting exotic properties which could revolutionize entire industries practically overnight. Room temperature superconductivity and the like are obviously enticing possibilities, but I've already seen demonstrated in a paper last year a high entropy alloy that demonstrated the unique and potentially quite useful property of actually getting harder and tougher as it was heated. The possibilities for meta materials approached by the method of multiplicative equi-molar elemental formulation is quite possibly the most exciting and likely branch of science to give us a concrete technological leap in the near term future (imho).

  • @hihihirenx1513
    @hihihirenx1513 15 днів тому

    Really high-quality video. Still trying to wrap my head around parts and really understand them, but it's getting there. Thanks!

  • @MeepMu
    @MeepMu 17 днів тому +1

    This is probably the most clear explanation of entropy I have ever heard

  • @theunseen010
    @theunseen010 17 днів тому

    Well now I need to look up how 3-angstrom pores for RO filters are manufactured..
    Amazing video as always AP. You share the pinnacle of science education on UA-cam with a very, VERY small crowd. Your effort is much appreciated!

  • @skylerbowerbank5847
    @skylerbowerbank5847 18 днів тому +2

    This video reminded me of an interesting quote
    "If you have an apple in a sealed system and watch it decay, if you wait long enough the molecules in the system will randomly reassemble themselves into an apple again, and a banana, and an orange, and a human hand" this was late explained that it would take longer that the heat death of the universe, but it's still amazing to think about

    • @devluz
      @devluz 17 днів тому +1

      This is always what confuses me with entropy. It is almost like time plays an active role in this. Not just as a dimension but almost like time can do work.

    • @skylerbowerbank5847
      @skylerbowerbank5847 17 днів тому

      @@devluz I've always thought the confusion was because infinity was involved myself, but the idea of time doing work, I never thought of that, that's quite the interesting idea

    • @marksizer3486
      @marksizer3486 14 днів тому

      See also Boltzman Brain.

  • @niictar
    @niictar 18 днів тому +2

    My goodness what a career ahead of you

  • @Not_Even_Wrong
    @Not_Even_Wrong 18 днів тому +1

    The reason is so easy to tell when your colliding spheres footage is played backwards it's because the collisions are inelastic, the spheres are BOTH slightly slower after, which is a small but noticeable effect. If we had perfectly elastic collisions or would be impossible to tell.

  • @alxk3995
    @alxk3995 19 днів тому

    Love your work 💜
    The joke with the lottery is right down my alley. 😂

  • @PensContinuingEducation
    @PensContinuingEducation 17 днів тому

    Thank you so much for this demonstration! As ever, you really got me thinking about something I already "understood."
    This time just thinkin about how it's funny that we describe a perfect equillibrium as "more disordered" than an "unstable/unlikely" arrangement

  • @katherinek6166
    @katherinek6166 17 днів тому +1

    Having three of one outcome and 1 of the other IS the most likely outcome for 4 coins. There are 6 permutations of HHTT vs 4 of HHHT and 4 of HTTT for an 8 total. And this holds for larger sets. If you have an even number of coins, being 1 flip away from perfect 50/50 split is the most likely outcome, and it is nearly twice as likely as an even split for large number of coins. The reason is that having N+2 heads and N-2 tails is almost exactly as likely as having N heads and N tails, but now we also have N-2 heads and N+2 tails as the second option, giving you nearly double the odds of not being perfectly even.

    • @AlphaPhoenixChannel
      @AlphaPhoenixChannel  17 днів тому

      95% ink and 5% water isn’t the same as 5% ink and 95% water, but they both have the same entropy of mixing

  • @starman5028
    @starman5028 17 днів тому

    This channel Is a gem

  • @johnnybodybags3994
    @johnnybodybags3994 7 днів тому

    I started watching this video, expecting explanations on probability alone, but was pleasantly surprised by your relations and applications to both physics and chemistry! I hand a like and sub to u sir! 😂 thanx for the quality content 👌👍

  • @Bojangus-
    @Bojangus- 17 днів тому

    The last time I felt so enthralled by a subject but also needed to rewatch the video again and again was Vsauce’s “What is down?” video. This is amazing, thank you

  • @don_lock
    @don_lock 18 днів тому

    Damn I love this channel!
    At the end when you said you might shake the system for a very long time and cause the ink and water to separate, but that it's just not gonna happen in reality, we could say instead that it is not gonna happen 'in the lifetime of the system' since the wood, glass, etc. will deteriorate before the ink and water separate.
    You could also say 'in your lifetime' but humans live such a short time I'll go with the system's lifetime.
    (Yeah, with infinite time and a never deteriorating system it will, 100 percent, separate.)
    I know you know ALL OF THIS but I wanted to state it for the record!

  • @theDebel1
    @theDebel1 5 днів тому

    You just gave me an 'aha!' moment when you're separating the ink from the water. That's exactly what is also being done in a desalination plant, as seen in Practical Engineering's video.

  • @RipRoaringGarage
    @RipRoaringGarage 13 днів тому

    Cute visuals. I love using excel too for things like this. But you gave me some inspiration on some number theory. Funny how things can tie together.

  • @0xTJ
    @0xTJ 19 днів тому

    Great video with some clever demos!

  • @andonel
    @andonel 18 днів тому

    what a beautiful demonstration

  • @TechMage299
    @TechMage299 16 днів тому +1

    I got invited to a superbowl gambling squares games at work. The goal is to try and match the lazt digits of each teams scores at the end of every quarter. And looking at final scores specifically, the most common digits were 4, 7, and i think 0. I tallied about 30 different games. So i got lucky and got 4' and 7's for my squares. Entropy, a never ending cycle

    • @mal2ksc
      @mal2ksc 15 днів тому

      This is why the numbers that go along the sides aren't assigned until all the squares are sold. The way I've usually seen to assign numbers is to pull ace through ten of any suit of playing cards to randomly assign the order. Dice are no good here, they have no "memory".

  • @sudokucoach
    @sudokucoach 19 днів тому

    Absolutely awesome video!

  • @fendgl9871
    @fendgl9871 19 днів тому

    I would love a video explaining energy, I've never really y understood it before. Great video again!

  • @4m0d
    @4m0d 19 днів тому

    what a beautiful video and demonstration

  • @TimpBizkit
    @TimpBizkit 13 днів тому

    For the first clip, the energy loss in partially elastic collisions tends to more evenly distribute velocity or momentum. Also due to the square law for energy and speed, two balls at even speed contain less energy than one very fast and one slow.
    In a perfectly elastic collision, firing a ball dead on into a stationary ball makes the first ball stop and the second ball carry the initial velocity. This is because the rebound (in the frame of reference that both balls are at half velocity coming towards each other) reverses the momentum of each one. That means in the original frame, one stops and the other starts. In a perfectly inelastic collision, both balls stick at half velocity in the direction of the moving ball. The remaining mv^2/2 energy is absorbed. Although on a smaller scale it's just bouncing atoms around inside each ball, that eventually bounce air atoms and the heat energy escapes.

  • @Velodreamer
    @Velodreamer 18 днів тому

    Thank you! Finally, I understood exactly how trees pump water to a height! They have membranes in each cell, and the juice contains sugar.

  • @pizzacrusher4632
    @pizzacrusher4632 18 днів тому

    what a super explanation. thank you very much!!

  • @xslayer88
    @xslayer88 9 днів тому

    I love the explanation that entropy isn't some law governed by some convoluted physical process... It's just the fact that the math in such huge systems of particles demands it.
    I've always seen where someone will say that in an infinite universe every possible combination will occur an infinite number of times and that thought kinda hurts my brain lol. I like the idea here more that if we're just limiting ourselves to a finite system, like the observable universe, those extremely unlikely combinations will never happen.
    Great vid as always!

  • @jherbranson
    @jherbranson 18 днів тому +1

    It actually makes perfect sense that low entropy states are notable to the human eye. Distinction and uniformity must be much of what we find in beauty.

  • @gregiep
    @gregiep 18 днів тому

    LOVE the mixed units on the water column math! Math king, right here.

    • @AlphaPhoenixChannel
      @AlphaPhoenixChannel  18 днів тому

      It’s really just to watch the all metric all the time people twitch in the comments. Any time I can refer to a sheet of plywood as 4x8 feet, 5mm thick, I do 😁. Nah in actuality I end up thinking in mixed units all the time. I regularly pump long mixed strings like that into wolfram cause it requires no thought

  • @DillonChichester
    @DillonChichester 13 днів тому

    This video finally made me understand entropy. When you said it was more of a statistical law than a physical one, I understood it a lot better, “technically” you can have certain things happen, but it isn’t practical to base your rules and laws around that