Entropy Confusion - Sixty Symbols

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  • čas přidán 2. 11. 2014
  • Professor Phil Moriarty talks about Entropy (again).
    Reddit discussion: redd.it/2l6ekd
    A little extra bit from this interview: • Entropy (extra intervi...
    An article Phil wrote after this video: physicsfocus.org/moriarty-conf...
    LINKS TO MENTIONED VIDEOS & RESEARCH
    The first entropy videos --- • Entropy - Sixty Symbols and • Entropy - Professor's ...
    Daan Frenkel: www.ch.cam.ac.uk/person/df246
    Sharon Glotzer’s group: sitemaker.umich.edu/glotzergro...
    TEDx talk from Glotzer: • Transforming Nanoscien...
    Disorder: A Cracked Crutch (not free to read): pubs.acs.org/doi/abs/10.1021/e...
    Visit our website at www.sixtysymbols.com/
    We're on Facebook at / sixtysymbols
    And Twitter at #!/periodicvideos
    This project features scientists from The University of Nottingham
    bit.ly/NottsPhysics
    Sixty Symbols videos by Brady Haran
    A run-down of Brady's channels: bit.ly/bradychannels
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Komentáře • 1K

  • @tmjcbs
    @tmjcbs Před 9 lety +2110

    Confusion about entropy always increases

    • @raykent3211
      @raykent3211 Před 9 lety +24

      As the chef said when asked to hurry up with the food for a particular table: "dis-order or dat-order?".

    • @SoberBro
      @SoberBro Před 9 lety +7

      tmjcbs I love your comment.

    • @ramonsantiago4573
      @ramonsantiago4573 Před 8 lety +5

      +tmjcbs or it doesn't change (isentropic process)

    • @ronanmcintyre
      @ronanmcintyre Před 8 lety +5

      I wish CZcams mobile would let me upvote this

    • @tanveerhasan2382
      @tanveerhasan2382 Před 8 lety +3

      I concur

  • @disgorgeengorge
    @disgorgeengorge Před 9 lety +231

    I like the way Baierlein (Thermal Physics p.44) describes it in my textbook:
    "You may, however, sometimes hear entropy characterized as 'a measure of disorder.'
    [...] The words 'order' and 'disorder' are colloquial and qualitative; nonetheless they describe a distinction that we are likely to recognize in concrete situations, such as the state of someone's room.
    [...] Imagine a bedroom with the usual complement of shoes, socks, and T-shirts. Suppose, further, that the room is one that we intuitively characterize as 'orderly.' Then, if we see one black dress shoe of a pair, we know -- without looking -- that the other shoe is right next to it. If we see one clean T-shirt, then the others are in a stack just below it. There are strong correlations between the shoes in a pair or the T-shirts on the dresser. Those correlations limit severely the ways in which shoes and T-shirts can be distributed in the room, and so the objects exhibit a small multiplicity and a low entropy.
    Now take the other extreme, a bedroom that we immediately recognize as 'disorderly.' If we see one jogger, we have no idea where the other jogger is. Under the dresser? Behind the bed? Lost in the pile of dirty T-shirts? And, for that matter, what about the T-shirts? If we see one on the dresser, the next clean one may be on the desk or in the easy chair. Correlations are absent, and the objects enjoy a large multiplicity of ways in which they may find themselves distributed around the room. It is indeed a situation of high entropy.
    There is usually nothing wrong with referring to entropy as 'a measure of disorder.' The phrase, however, doesn't take one very far. To gain precision and something quantitative, one needs to connect 'disorder' with 'absence or correlations' and then with multiplicity. It is multiplicity that has sufficient precision to be calculated and to serve as the basis for a physical theory."
    TL;DR.
    Order Strong correlation Small multiplicity
    Disorder Absence of correlation Large multiplicity

    • @luciuspertis5672
      @luciuspertis5672 Před 5 lety +5

      this really helped ...... thanks :)

    • @ceruchi2084
      @ceruchi2084 Před 5 lety +2

      How does order come out of entropy in this analogy? The messy guy tosses his shoes around and sometimes the two black shoes wind up next to each other by chance?

    • @xCorvus7x
      @xCorvus7x Před 4 lety +11

      @@ceruchi2084 Imagine that the shoes have some sort of adhesive between them so that they stay together once they end up next to each other once.
      This is, I think, how the forming of crystal structures (i. e. chemical bonding) works: the electrons in the free moving atoms have more energy than those in the bond, so if two atoms interact (i. e. happen to be next to each other), the chemical bond is created while the electrons give off that energy as heat.
      That's also what happens when some thing burns.

    • @TextiX887
      @TextiX887 Před 4 lety +3

      @@xCorvus7x The guy has OCD and allways place the items in the same way.

    • @xCorvus7x
      @xCorvus7x Před 4 lety +1

      @@TextiX887 Basically, yes.

  • @chrisofnottingham
    @chrisofnottingham Před 9 lety +255

    The only way this is helpful is that it makes clear I have no idea what entropy is.

    • @chrisofnottingham
      @chrisofnottingham Před 9 lety +1

      I will!

    • @markymark863
      @markymark863 Před 4 lety +4

      The number of ways you can rearrange the particles of something and still end up with the same structure. For example, a sand castle has lower entropy than a sand pile.

    • @MrJonsonville5
      @MrJonsonville5 Před 3 lety

      It's disorder, pay attention!

    • @praagyadhungel1357
      @praagyadhungel1357 Před 3 lety +4

      @@markymark863 So what you're trying to say is that the no. of ways sand particles can be arranged so it forms castle structure is less than no. of ways in which sand particles can be arranged so that it forms a pile?

  • @sixtysymbols
    @sixtysymbols  Před 9 lety +77

    And there's a little extra bit: czcams.com/video/maWvwuYR4VA/video.html

    • @govindschavan
      @govindschavan Před 9 lety +11

      Thank you brady for uploading the extra bit so quickly. I felt that the discussion would not have ended at that with you being there and all.

    • @ThePeaceableKingdom
      @ThePeaceableKingdom Před 9 lety +17

      Bravo for revisiting an earlier video!
      The very essence of science is revision, so Bravo!

    • @88Cardey
      @88Cardey Před 9 lety +5

      Your best videos come from Phil Moriarty, even when you don't fully understand what he's talking about he's still really interesting to listen to. You can tell he's very passionate about his work. 
      Amusing extra footage as well.

    • @sachighmedia
      @sachighmedia Před 9 lety +1

      That extra bit is totally worth it! Awesome.

    • @PhilHibbs
      @PhilHibbs Před 9 lety +10

      88Cardey
      Also, he's called Professor Moriarty, how cool is that?

  • @chris11sholtz
    @chris11sholtz Před 8 lety +40

    I think Brady has one of the best jobs in the world.

  • @Banana39489
    @Banana39489 Před 9 lety +95

    Anyone worse off after watching this video? Or is it just me?

    • @salottin
      @salottin Před 4 lety

      Remember Socrates

    • @turgidbanana
      @turgidbanana Před 4 lety

      "worse off"? Nah I feel fine. 🤷‍♂️

    • @TheSkullConfernece
      @TheSkullConfernece Před 4 lety +1

      This video clarified a lot for me.

    • @joboring8397
      @joboring8397 Před 3 lety

      It takes a lot to begin wrapping your head around it. Studying statistical mechanics and learning to implement Molecular Dynamics starting from statistical mechanics principles will do the trick.
      I realize this comment is six years old... so, were you able to eventually gain a better understanding?

  • @hobowithashotgun48
    @hobowithashotgun48 Před 9 lety +102

    Entropy is the observable tendency of matter to assume the most stable state based on statistical energy distribution. Usually, this manifests itself as "disorder" especially when we talk about gases or liquids. The key thing is to get people to stop thinking of entropy as a force that "does something" (as too many professors teach in undergraduate thermodynamics), but instead as an observation or measurement that can inform us about other aspects of whatever we are examining.

    • @francoislacombe9071
      @francoislacombe9071 Před 9 lety +5

      In other words, entropy is a process, not a substance, the way heat is a process and not a substance. Could people be making the mistake of thinking about entropy as something similar to phlogiston? That could explain a lot.

    • @TheVino3
      @TheVino3 Před 9 lety +10

      EXACTLY.
      I am sooo tired of people talking about entropy as if it is a force that is exerted on the universe by something. Entropy is just the way we describe the natural tendencies of matter to distribute itself - as you say.
      Entropy isn't a "real" thing.

    • @mountainhobo
      @mountainhobo Před 9 lety +10

      hobowithashotgun48 "Entropy is the observable tendency of matter to assume the most stable state based on statistical energy distribution."
      Hobo (funny coincidence), is that yours? I've googled for that exact quote but could not find it. This is the most succinct and clearest explanation I have heard. Is physics your profession?

    • @RyanGatts
      @RyanGatts Před 9 lety +3

      Best comment. I think this is my favorite comment at least of this week, if not of this year. Very well done explanation.

    • @hobowithashotgun48
      @hobowithashotgun48 Před 9 lety +11

      mountainhobo Yes, it's my own explanation. I formulated it while teaching chemistry prior to starting grad-school. There is nothing better for improving your own understanding of a concept than trying to explain it to someone else.
      My background is in biochemistry, which I actually think is better for understanding entropy than physics: In physics you focus on the more abstract mathematical definition, which may not fully convey the nature of the concept. In biochemistry on the other hand you cover very practical applications of entropy such as predicting protein folding based on molecular interactions. Who knew that hobos are so into science?

  • @MishunHSugworth
    @MishunHSugworth Před 9 lety +4

    Great video, charismatic, engaging and concise delivery. Nice back story with the frustration over previous work and explaining flaws with entropy descriptions. Nice touch with the citations too. More of this please.

  • @ilkeryoldas
    @ilkeryoldas Před 9 lety +241

    Entropy isn't what it used to be :(

    • @RQLexi
      @RQLexi Před 9 lety +31

      Entropy isnt' waht it usde et:b (o

    • @KemaTheAtheist
      @KemaTheAtheist Před 9 lety +14

      I see what you did there.

    • @MarshmallowRadiation
      @MarshmallowRadiation Před 9 lety +9

      That's right... because it's always increasing! (ha HA!)

    • @Naijiri.
      @Naijiri. Před 9 lety

      ***** You dont see what he did there, its already gone.

    • @imranhq13
      @imranhq13 Před 7 lety +1

      i can't see what he did there

  • @elchippe
    @elchippe Před 8 lety +135

    Entropy is a measurement of dispersion of energy in a system, an increase of entropy means that becomes more difficult to extract energy in a system, the appearance of order or disorder is irrelevant to entropy by example if you order all the atoms, particles and matter in the universe equidistant to each order, gravity cannot work, so entropy will be at its maximum but the universe will look very orderly.

    • @vealck
      @vealck Před 8 lety +2

      +elchippe This is a very elegant example.

    • @patrickleahey4574
      @patrickleahey4574 Před 8 lety +1

      So, a diamond appears very orderly but difficult to get energy from it.

    • @iamBrian4444
      @iamBrian4444 Před 8 lety +3

      diamonds are actually flamable

    • @stevo728822
      @stevo728822 Před 7 lety

      So increasing entropy is increasing predictability?

    • @EebstertheGreat
      @EebstertheGreat Před 7 lety +8

      stevo728822 No, it's almost exactly the opposite. A highly predictable system, like a crystal, generally has very low entropy. The OP is basically just wrong.

  • @sypen1
    @sypen1 Před 7 lety +47

    i think im more confused then ever

    • @vinitchauhan973
      @vinitchauhan973 Před 6 lety +6

      That means you understand it better than you did before

  • @ErlendBarkbu
    @ErlendBarkbu Před 2 lety +1

    I’m seldom able to personally attach very much feeling or muster very much enthusiasm to any subject. I really like the way Professor Moriarty is able to convey his enthusiasm and sincerity about these subjects. It gives me so much value when I watch these videos

  • @arthur78
    @arthur78 Před 9 lety +5

    Entropy is one of my favorite topics in Physics, and I haven't watched the previous videos on it. But very much enjoyed this one.

    • @petevenuti7355
      @petevenuti7355 Před rokem +1

      How many different ways have you found it defined? Yes the standard book definitions are pretty consistent, but when you try to derive an *operational definition* from the ways it's often explained or used, the definitions seem wildly contradictory.

  • @charh675
    @charh675 Před 8 lety +6

    I'm a computer science major, but damn does your content make me interested to learn more than the required physics and chemistry. I really enjoy the quick education type of content on youtube, I can't get enough of it.
    I would love if you put an interesting math problem in the info section related to each video.

  • @BrianBlock
    @BrianBlock Před 9 lety +2

    I am so happy to see another video on entropy. This is one of the most difficult concepts for most people, due to all the reasons he went over (the oversimplification of entropy as order versus disorder is probably the biggest culprit). Thank you Phil and Brady!

  • @brianpso
    @brianpso Před 9 lety

    This video clarified the subject a lot to me. Thanks a lot Prof. for being so interested in finding the best way to explain these concepts to us, I really appreciate it.

  • @theoneallinblack
    @theoneallinblack Před 4 lety +3

    Love this guy! Great respect for his passion for science and explanation.

  • @fakjbf
    @fakjbf Před 9 lety +12

    One way I think of it is like dropping a ball. Yes, there are thousands of directions the ball could go in, but it's always going to go straight down because gravity is acting on it. You always have to take into effect inputs of energy, because that wildly distorts the probabilities of one outcome over another.

    • @blitzucan
      @blitzucan Před 9 lety +1

      What does your profile picture mean?

    • @Banana39489
      @Banana39489 Před 9 lety +5

      Declan Siewert Minas tirith/White tree of Gondor

    • @RQLexi
      @RQLexi Před 9 lety +2

      Declan Siewert Elaborating on Banana's answer, it is the flag of Gondor in Tolkien's Middle Earth, showing the white tree of Gondor combined with the seven stars of the House of Elendil and, though not seen in fakjbf's profile picture, crowned with the crown of the King. It is the symbol both of Gondor's line of great kings and of the kingdom as a whole.

    • @unvergebeneid
      @unvergebeneid Před 9 lety +3

      The Ainur could decrease entropy. True story.

  • @jriccioj
    @jriccioj Před 8 lety +1

    This video made me cry. I have finally understood entropy. Thank you, professor

  • @darkseid9098
    @darkseid9098 Před 8 lety

    You're like the first person on the internet to clear up this confusion, thank you.

  • @EGarrett01
    @EGarrett01 Před 7 lety +12

    So...entropy is basically the tendency of closed systems to form into more likely arrangements and not the tendency of closed systems to become more disordered?

  • @sidewaysfcs0718
    @sidewaysfcs0718 Před 9 lety +6

    now, here's a small problem, the entropy IS going up, but NOT in the crystal, it goes up in the entire system , which in our case is the universe
    if you would consider a smaller system, like an isolated room, with some ions inside, eventually the ions will clump together and form the low-entropy crystal, but that will ALWAYS release heat, and the heat will drive the entropy of the room higher, even if there's a vacuum in the room, the total entropy will still be higher because now the disorder of the energy inside the room is higher than any possible disorder the initial ions might of had

  • @eltyo340
    @eltyo340 Před 9 lety +2

    I love how Phil just gets up and struts around in his excitement xD Brady's camera is just all over the room

  • @ToothTalks
    @ToothTalks Před 9 lety +1

    Phil, thanks for persuading Brady to pursue this. As an Armchair Physics fan, I've been researching terms like "Does Life = Negative Entropy" precisely because of the Entropy Confusion that you explain here. I've looked into Shannon's Entropy with regard to the number of bits of information and followed it through to Lenny Suskind's lectures on Black Hole Entropy and it all seems at odds with the laws of thermodynamics and Brian Cox's sandcastle analogy. Sure, there's a grey area for for popular science and there's a definite area for career scientists, but there is a middle ground for folk who want more than BBC science, hence why we turn to you guys - please keep pushing it the direction you're going as it is great to have people who really know their stuff impart their knowledge at a level beyond "6 cans of stella and a chicken tikka" level - there is a thirst out there for grown up science and I love the fact you are willing to give us that - well done you!

  • @satanas1729
    @satanas1729 Před 9 lety +10

    how about a series of videos? Entropy is a pretty interesting topic and, as shown in this video, seems to be pretty complex too. A few more videos into that might clear things up a bit for all of us

  • @unvergebeneid
    @unvergebeneid Před 9 lety +57

    So what is entropy _really_? Apparently, the answer is "it's complicated."

    • @istvankleijn3643
      @istvankleijn3643 Před 9 lety +18

      Simplicity is a lie.

    • @SillyPutty125
      @SillyPutty125 Před 9 lety +29

      Entropy is a measure of the number of ways a system can be in a state.
      For example, suppose I have 5 coins. Here's the number of ways for me to have X heads.
      X | ways
      0 | 1
      1 | 5
      2 | 10
      3 | 10
      4 | 5
      5 | 1
      What this means is that if you were to continuously flip the coins, you would very often see 2 or 3 heads (disordered), and very rarely 0 or 5 (ordered). Therefore, the disordered states have higher entropy.

    • @Dasmaster1
      @Dasmaster1 Před 9 lety +1

      Simplicity is harder to understand then complexity.

    • @SillyPutty125
      @SillyPutty125 Před 9 lety +1

      *****
      I think you mean truth is stranger than fiction.

    • @Dasmaster1
      @Dasmaster1 Před 9 lety

      SillyPutty125
      I am not trying use fancy quotes here. I am just saying Simplicity is harder to understand then complexity. I can much easier understand any number of instructions on how to for example close a door but having the "simplest" explanation which you could argue for example be Math makes absolutely no sense to me and would require me to learn allot to even have a basic understanding.

  • @bruinflight1
    @bruinflight1 Před 9 lety

    Thank you Professor Moriarty for following up on this theme and unpacking the complicated feature called entropy. Thanks Brady, you ask a lot of good questions as well for the layman like me. Another thoroughly enjoyed Haran video!

  • @twicebittenthasme5545
    @twicebittenthasme5545 Před 9 lety

    I just want to say the coverage of the various topics, though brief, is informative and intriguing. These video shorts have piqued my interest and have been the impetus for a number of follow-up searches (by me, of course) into the myriad of subjects covered.
    Thank you, to all contributors, for sharing and I certainly am looking forward to the many left to watch. Keep up the fantastic work!

  • @jamesneace5559
    @jamesneace5559 Před 8 lety +8

    'This is from a kid's crystal growing kit'. Unless it's in my hands, and then it becomes an adult's crystal growing kit. :)

  • @xenomann442
    @xenomann442 Před 9 lety +5

    Brady you made a video for PeriodicVideos a few years ago called "Becoming a Chemist - Viewer Questions". It would be interesting to see a similar video for SixtySymbols.

  • @dit-zy
    @dit-zy Před 9 lety +1

    THANK YOU! The order-disorder description of entropy has made me uncomfortable for so many years, but I keep hearing people defend it. I understand how it's a useful tool to casually explain to someone unfamiliar with physics what entropy is -- especially because entropy is so complex -- but while it's a handy intro to the concept, people are often given only that explanation, and in that situation I've seen it leave too many people with really bad notions of entropy that they use to convince themselves of very wrong ideas. I'm really glad you made this video. You have a chance to get a lot of vision on this issue with people who wouldn't otherwise find out about it.

  • @Tracy_AC
    @Tracy_AC Před 9 lety

    This video really captures the essence of what science is all about: modeling the real world, trying to understand how things are related, and continually revising your understanding to better fit with the evidence. Things may be complicated and difficult to explain, but that just makes them all the more interesting.

  • @dante224real1
    @dante224real1 Před 8 lety +3

    continue to fight entropy every day gentlemen! i'm 100% behind you!

  • @TestMeatDollSteak
    @TestMeatDollSteak Před 9 lety +135

    I must bookmark this video for the next time I encounter a creationist who cites the second law of thermodynamics as a "refutation" of biological evolution.

    • @Plusimurfriend
      @Plusimurfriend Před 9 lety +20

      i still dont understand what thermodynamics has to do with biology. they assume that earth is a closed system so life cannot exist here without some special intervention, but precisely because its not a closed system i.e. the sun, life could evolve here.

    • @epiclegodude123
      @epiclegodude123 Před 9 lety +17

      Please do. I love it when creationists think they know science, then you correct them and their smile goes away from there face and they get defensive with all their answers

    • @Axartsme
      @Axartsme Před 9 lety +9

      Or just show them SMBC number 3340

    • @MarshmallowRadiation
      @MarshmallowRadiation Před 9 lety +3

      Don't forget to also cite Veritasium's video "What is NOT Random" whenever they bring up "information," too.

    • @HamPuddle
      @HamPuddle Před 9 lety +3

      Plusy Thermodynamics has everything to do with biology...

  • @TheSkullConfernece
    @TheSkullConfernece Před 4 lety

    This video helped understand entropy so much better. Thank you professor!

  • @EL-mg9st
    @EL-mg9st Před 9 lety

    Thank you so much for providing the videos and website. 60 Symbols really makes a difference for those of us on the outside looking in. Very accessible.

  • @jfuite
    @jfuite Před 9 lety +4

    Start again from scratch! Make a THIRD video. Do not apologize for, or refer to, the first pair of videos. Take a deep breath, figure out what the hell entropy is, and then explain it to us well.

  • @aeroscience9834
    @aeroscience9834 Před 9 lety +5

    Yes! Finally a video saying entropy is not disorder

  • @heheheheheeho
    @heheheheheeho Před 9 lety

    I've missed videos with Phil! Like him the most

  • @tekinay004
    @tekinay004 Před 7 lety

    I love Professor Moriarty's energy when he does the videos!!

  • @TheNuncFluens
    @TheNuncFluens Před 8 lety +46

    Isn't the concept of order an intrinsically human thing? I mean an arrangement of particles that can look disordered to us might have an underlying order that isn't obvious to a human observer.

    • @KWGTech
      @KWGTech Před 8 lety +31

      Actually, there is a concrete definition of order, but some systems that are technically ordered may not seem ordered to humans.
      This is not a scientific definition of order, but it is a definition consistent with the common explanations of entropy and the common intuition of what order is.
      Order describes a set of conditions for which there are relatively few ways to satisfy.
      For example, if were comparing sandcastles and sand dunes, there only a few ways to arrange grains of sand in a fashion that would seem to me like a sand castle in comparison to the many, many ways to arrange sand so that it fits my definition of a dune. Therefore, sandcastles are more ordered than dunes.
      Similarly, there are only a few ways to arrange a deck of cards (in fact, only 24) such that all cards of the same suit are together, and the value of the cards are ascending (within each suit), but there are many ways to arrange the cards in no particular order i.e. a random shuffle (about 8 x 10^67 ways). Therefore a shuffled deck is _less_ ordered.

    • @MrGoatflakes
      @MrGoatflakes Před 7 lety +7

      You are touching on the philosophy of maths and science here. My view is that all these things we talk about in science are properties we have observed in physical systems, so they more or less exist independently of human thought, in so much as they correctly describe physical reality.
      You could argue that mathematics and logic have this property, Maths because it is derived from measuring and counting and other ways of observing physical reality, thinking about it and seeing if an idea we have come up with is somehow useful.
      In science useful means it both explains something about reality and also predicts something new in reality, but in mathematics we are looser in our definition of utility, and say anything that is interesting and somehow logically consistent as useful.
      Even logic can be seen in this way, seen as the codification of those approaches to reasoning which has proved successful in the past. I.E. those which have reached conclusions which have eventually been proven correct.
      People, even scientists and mathematicians, are often very surprised when some seemingly unrelated obscure branch of mathematics finds sudden application to some field of scientific inquiry. Often it almost seems like the mathematics was purpose built for that branch of science, even though it was invented independently.
      But should it really be a surprise, given that mathematics started off as measuring and counting of the real world and that it developed by applying reasoning and imagination to these foundations, and then checking that what results makes some sort of logical sense? Why should we be surprised then when we invent something that later on seems perfect to describe some aspect of physical reality?

    • @saeedbaig4249
      @saeedbaig4249 Před 7 lety

      Watts the concrete definition?

    • @KWGTech
      @KWGTech Před 7 lety +2

      Sideeq Mohammad "Entropy is a measure of the number of microscopic configurations Ω that correspond to a thermodynamic system in a state specified by certain macroscopic variables." en.wikipedia.org/wiki/Entropy

    • @williambrandondavis6897
      @williambrandondavis6897 Před 5 lety

      @@KWGTech How does that work if we have an infinite number cards? With an infinite amount of cards every combo could be ordered but it would be beyond our scope of perception would it not?

  • @ricochet188
    @ricochet188 Před 9 lety +12

    "AAAAAAAAAAH" - Me after trying to understand this video

  • @timeslowingdown
    @timeslowingdown Před 9 lety

    Thanks for making this video, I've been aware for a while that describing entropy as a measure of order is very misleading. Describing it as the number of ways you can create a specific state is a much better way. Glad this video was made.

  • @BBriscoe
    @BBriscoe Před 9 lety

    I've been introduced to chemistry in high school and in college. So, I have a general understanding of entropy and enthalpy. I was interested in the scenario where entropy resulted in a more ordered system. I would be happy to sit and listen to a full lecture, and / or future videos on this topic.

  • @christianmarin6267
    @christianmarin6267 Před 9 lety +10

    this guy loves what he does. always energetic

    • @BRAgi-zs3mf
      @BRAgi-zs3mf Před 3 lety

      It would help if he knew what he is taking about!!!

  • @combatjm89
    @combatjm89 Před 9 lety +3

    I think the vid's title is appropriate - my brain system is closed and in a high state of confusion... time to do some reading on this.

    • @mikew1990hello
      @mikew1990hello Před 9 lety

      forgot to add I also absolutely love the sixty symbols videos (all of Brady's channels are awesome but I'd totally have sex with physics if I could so of course sixty symbols is my favourite!)

  • @Cythil
    @Cythil Před 9 lety

    I am so glad that this video was made! I have been arguing for not using disorder to describe entropy for a very long time! Thank!
    (I might even have made a post in the past one of these videos about it)

  • @nathanroberson
    @nathanroberson Před 4 lety

    Thank you. Thank you for all you videos. They are empowering. I ponder entropy all the time. And starve for higher detail.

  • @Ancor3
    @Ancor3 Před 9 lety +184

    I'm betting that someone is going to turn this into a religious discussion.

    • @ericlin4971
      @ericlin4971 Před 9 lety +29

      Yeah it's annoying. You just know someone's gonna go: "this is proof God exists, only God could do something like that"

    • @MomentousGaming
      @MomentousGaming Před 9 lety +22

      I give it 6.67 seconds give or take.

    • @OrangeFiero
      @OrangeFiero Před 9 lety +42

      You just did haha.

    • @tedchirvasiu
      @tedchirvasiu Před 9 lety +24

      this is proof God exists, only God could do something like that

    • @yearswriter
      @yearswriter Před 9 lety +11

      yes, you just did. Otherwise this channel usually better in that regard

  • @BerkSarikaya
    @BerkSarikaya Před 9 lety +11

    I love this man!

  • @illustriouschin
    @illustriouschin Před 9 lety

    Thanks for setting the record straight doc!

  • @bpresgrove
    @bpresgrove Před 9 lety

    I worked in the nuclear industry as a radiation control technician and learned alot about the nuclear world as it relates to radiation and atoms. But listening to yall I realize just how much I love science. Even though im not a scientist, my degree is in operations and project management, I have learned so much from your videos. Please keep up the awsome work you are doing it is wonderful.

  • @BookofAeons
    @BookofAeons Před 9 lety +13

    Why do your headphones always come out of your pocket tangled? Entropy!
    Shoving them in there and walking around in effect randomizes their position. Since there are far more ways to tangle a string than there are to keep it perfectly coiled, the odds are your headphones will come out tangled.

    • @AltainiaInfinity
      @AltainiaInfinity Před 9 lety +4

      What's more: once it becomes slightly tangled, the movements that would untangle it are less likely to occur than the movements that either keep it in the same tangled state or make it worse. Thus, over time, statistically speaking, the headphones will reach ever increasing tangled-ness (assuming you have an infinite long headphone cord; in real life there would be a limit).

    • @severedize
      @severedize Před 9 lety +1

      My headphones go in my pocket neat and come out neat, evolution;)

    • @hauslerful
      @hauslerful Před 9 lety

      AltainiaInfinity That's how rubber bands work ;-) The polymer chains get tangled and thus shrink in size. Entropy is pulling rubber bands together.

  • @tchevrier
    @tchevrier Před 7 lety +12

    I'm not sure that was a better explanation.

  • @mariantheone
    @mariantheone Před 9 lety

    I have to say I'm finally very happy about that explanation, professor Moriarty. That's what I'm always saying: one cannot understand entropy without the Gibbs ensemble, because it's all about the number of microscopic representations of a given macro-state. I would add to that, that if ergodic hypothesis is satisfied, so the system is exploring every micro-state with equal probability making the time averages equal to the ensemble averages, the second law of thermodynamics becomes a trivial statement. It simply means that the system will evolve to a more likely state, i.e. having more microscopic representations.
    I think you explained very well what the entropy is exactly, formula and all. Thanks.

  • @jrandall15ec
    @jrandall15ec Před 9 lety

    As someone who just spent something like 6 or 7 weeks of P-Chem this whole video, and Brady's questions in the video just make me smile because of how complicated and interrelated all of the thermodynamic values are.

  • @fransmulder9326
    @fransmulder9326 Před 8 lety +5

    Hmm I can see the guy is passionate about th topic. The message however is a little difuse, maybe making a video with a little more preparation and focus on the message could be considered.

  • @DamianReloaded
    @DamianReloaded Před 9 lety +8

    This is what I find hard to grasp. If heat promotes entropy, how is it that our current universe, which is colder, has a higher entropy than, say, the universe when it was a few microseconds old (which was hotter)? There should be more ice crystals in the universe now than a few seconds after the big bang. If the universe is in fact a closed system, that's expanding thus making heat be less "potent" how is it that entropy increases within it?

    • @istvankleijn3643
      @istvankleijn3643 Před 9 lety +7

      What do you mean by "heat promotes entropy"? Remember that heat is a type of energy. You can add an amount of heat dQ to a system that has a temperature T. The second law of thermodynamics then says that the entropy of that system increases by an amount dS that is greater than or equal to dQ/T.
      Also, the entropy of a closed system never decreases. It can stay constant though, if the processes in the system are reversible.
      Doing thermodynamics in an expanding universe complicates things a bit... I recall from a cosmology course that the entropy scales at the same rate as the volume of the universe, but I do not remember and/or understand it well enough to explain it. Maybe someone else can :)

    • @seigeengine
      @seigeengine Před 9 lety

      Damian Reloaded Yeah, I'm pretty sure what you just said didn't make sense.

    • @DamianReloaded
      @DamianReloaded Před 9 lety +4

      seigeengine Probably, that's why I said I find it hard to grasp in the original post. Because I'm confused. Are you able to elaborate an enlightening answer, otherwise you don't look smarter than I. ^_^

    • @DamianReloaded
      @DamianReloaded Před 9 lety

      seigeengine Just because in the video Prof. Moriarty mentioned thermodynamics and heat as playing a key role in the whole concept of entropy?

    • @DamianReloaded
      @DamianReloaded Před 9 lety

      Istvan Kleijn Ok, but how does that answer the original question of a cooler expanded universe having an increased entropy in relation to a super heated smaller universe? I mean, if as you said, and I quote: "The importance of entropy depends on the temperature, when the temperature is twice as high, the entropy term is twice as important".

  • @andrewc874
    @andrewc874 Před 9 lety +1

    Thanks for making these videos! Fascinating stuff; keep it up!

  • @phelanii4444
    @phelanii4444 Před 7 lety

    we had a lecture about entropy today, and so many minds were blown.

  • @bookdream
    @bookdream Před 9 lety +12

    I hate how he keeps having to shorten what he's saying, I wish he could just have all the time he wanted to explain this concept as much as the average person could understand.

  • @Goodwithwood69
    @Goodwithwood69 Před 8 lety +21

    So entropy is..............

    • @katiebennie9245
      @katiebennie9245 Před 8 lety +8

      +Matthew Smith The amount of energy in a system unavailable to do work

    • @bxyify
      @bxyify Před 8 lety +13

      +Katie Bennie This or just the *amount of possibilities the particles of a system can be arranged*. The best example I heard was with a glass of beer:
      When beer is fresh from the tap, it has it's whitecap. Now a whitecap seems more disordered than the beer fluid because the fluid is nice, clear and smooth while the cap is a mess of bubbles. But if entropy always increases, why do I need to put energy into the system of beer (blowing into it for instance) to create new bubbles but when I just leave it alone, the cap vanishes. Because actually in the fluid the entropy is higher than in the cap, because the molecules in the cap are limited to the walls of small bubbles which gives the fluid particles less ways to be arranged than in the open fluid. When the cap vanishes over time, the entropy of the beer increases as the beer molecules sink into the open fluid and are free to float and arrange with the other molecules in the glass.

    • @ufotofu9
      @ufotofu9 Před 8 lety

      +bxyify This.

    • @supernaturalswampaids8083
      @supernaturalswampaids8083 Před 8 lety +2

      +bxyify
      I'm saving this! Perfect example. I know beer.

    • @matthewbrennan3127
      @matthewbrennan3127 Před 5 lety

      The number of ways that particles can be positioned

  • @MrDposter
    @MrDposter Před 9 lety

    I love how intense Moriarty gets about things in these videos........it let's you know he really cares about what he is explaining

  • @Shade_K
    @Shade_K Před 9 lety

    I still find entropy a very hard concept to grasp for a simple mind like mine, fuzzy analogies definitely don't help.
    But in the bright side, as I keep trying to wrap my head around it, I get a good excuse to revisit Professor Moriarty's videos, which is always lovely!

  • @TempestTossedWaters
    @TempestTossedWaters Před 9 lety +5

    I'd love to say I now understand more about entropy than I did before watching the video but the explanation here appears insufficient to me.

    • @TempestTossedWaters
      @TempestTossedWaters Před 9 lety

      ***** Not insufficient for a detailed and comprehensive understanding, insufficient to learn anything new at all. Which was kind of disappointing.

  • @ElDaumo
    @ElDaumo Před 9 lety +9

    mr moriarty really got old in the last 6 years. (but he aged well, so no offense)

    • @jayakumarrangaraj9993
      @jayakumarrangaraj9993 Před 8 lety +3

      +karottenkoenig That's Professor Moriarty for you.

    • @mal2ksc
      @mal2ksc Před 8 lety +2

      +karottenkoenig
      Either he was dyeing his hair before and no longer does, or being Sherlock Holmes's main adversary is really tiring. Maybe both.

    • @NGC6144
      @NGC6144 Před 8 lety

      +Scott Sakurai Or, it could be Heavy Metal poisoning.

  • @AudaciousAmber
    @AudaciousAmber Před 9 lety

    me and many others use the term rejuvenation with the body to stop entropy...giving the system as a whole what it needs to function correctly, while removing "obstruction" so you dont have continued entropy in weaker areas of the body
    ....very neat to watch this discussion and see all the ways we can figure out what happens on this rock floating thru space....

  • @imwithstupid086
    @imwithstupid086 Před 9 lety

    Brian Cox did a wonderful job explaining entropy in his series Wonders of the Universe. He explained by making a sand castle in the Namib desert. There is always going to be a lower number of possible configurations where the sand retains the shape of the castle, rather than the sand just being scattered in dunes.

  • @MariusMuntean
    @MariusMuntean Před 9 lety +6

    Explanation isn't very satisfying.

    • @vinitchauhan973
      @vinitchauhan973 Před 6 lety +1

      Explanations in quantum mechanics and thermodynamics aren't always satisfying

  • @mr.meeseeks5765
    @mr.meeseeks5765 Před 7 lety

    I've just watched your entropy videos and I was wondering, you said in your first video as time goes by the entropy of a system increases and it's incredibly difficult to reduce it but in the video simulation from the group at Michigan they showed the system getting more ordered and I'm a little confused what happens to entropy over time?

  • @nathanneiman
    @nathanneiman Před 8 lety

    Thank you for the excellent video. It's enough just looking to the universe to see how order is dominant, as the things are growing in complexity.

  • @story46
    @story46 Před 9 lety

    Moriarty is back!! Love it!!

  • @MeLlamoChopa
    @MeLlamoChopa Před 9 lety

    Love this guy! He's just incredibly passionate !!

  • @CastelDawn
    @CastelDawn Před 9 lety

    very clear and understable video, good work.

  • @atomcraft
    @atomcraft Před 9 lety

    About bloody time Brady! Sixty Symbols all the way. Love hearing Prof. Moriaty rant.

  • @DarkParadeHF
    @DarkParadeHF Před 9 lety +2

    I find the videos on entropy to be very interesting but to complex for the format of video that you guys keep releasing. Would it be possible to do a series of videos that explain the base models all the way up to the full complexity of entropy and disorder?

  • @Raddland
    @Raddland Před 9 lety

    Ways... that is a great way to visualize it. I think I will keep this in mind next time I get that blank look when I use the word "entropy" in the real world. Seems like a much better way to illustrate it to people who haven't heard of it before. Good vid :)

  • @JakeDavidHarrison
    @JakeDavidHarrison Před 9 lety

    The description of Entropy being described as the number of ways a system can be arranged is really what made this click for me, what used to throw me is that it's said the universe is constantly moving towards entropy (which is regularly used as a synonym for disorder) but in the heat death of the universe, all energy will be uniform, those 2 statements used to seem highly contradictory to me but I think I see what's meant now.
    Hopefully I have a correct understanding of entropy now, even if it is a minor one, thanks for the re-do of the video.

  • @insu_na
    @insu_na Před 9 lety

    Blue Snowball in the background :)
    I think you should do a feature length episode on entropy. There's so much that Prof. Moriarty seemed to want to say about entropy that didn't make the cut in this video (or the last one for that matter). I think entropy is one of the most interesting topics in physics.

  • @davidherrera8432
    @davidherrera8432 Před 9 lety

    Dr Moriarty, I have a question, where can I get some information (book or paper) in wich I can se the relation between a hard sphere model and the entropic part of the system?, I'm a physicist myself and a derivation of this relation will be extremly helpfull to me, so a pretty technical source will be perfect to me, and very informative.
    In advance, thanks for all.and sorry for the bad orthography.

  • @ismaeleye
    @ismaeleye Před 7 lety +1

    Would you please POST the TEDx video link.............
    Thanks

  • @hermanodecaer2840
    @hermanodecaer2840 Před 7 lety

    So is entropy related to the number of different spatial positions a molecule can occupy? In the paper from Lambert it is mentioned only that the energetic micro-states are important, I think (so molecule velocities, vibration frequencies etc.?). So which one is it?

  • @j9312
    @j9312 Před 9 lety

    This video actually made me forget what entropy is. Thanks allot Moriarty.

  • @karlkalkyl5557
    @karlkalkyl5557 Před 6 lety

    Hello!
    I know this is video was published some time ago but is there some way to reach the article Phil wrote after the video was made? The link in the description doesn't seem to work...

  • @Metalkatt
    @Metalkatt Před 8 lety

    I did wonder why there wasn't much mention of the energy part in the last video. I remember reading an excellent description that made perfect sense to me--you can tidy your house and put everything where it belongs, thus putting the objects in a low-entropy state, but the energy you took to do it, the biological energy and heat energy and mechanical energy and so on of you moving and putting those things in place, that still creates an increase in the overall entropy. You're burning energy in your muscles, exhaling CO2, radiating heat, and so on--that creates more entropy than what you took away by putting everything away.

  • @veronikavasickova4918
    @veronikavasickova4918 Před 9 lety

    Thanks!
    Is there a link between the entropy and chaos?
    Could you please do a video about non-linear dynamics?

  • @ericsbuds
    @ericsbuds Před 9 lety

    great video and explanation! Thanks guys

  • @dpapad202
    @dpapad202 Před 9 lety

    Why can't more of my university professors be like the guys on Sixty Symbols...
    Amazing once more

  • @nilayjain6043
    @nilayjain6043 Před 9 lety

    Brady, may i suggest prof. Moriarty make 2 or 3 videos on entropy one for beginners, one for people who took physic after high school and one for experts like his colleges in non physics areas like professional researchers and scientists. i can see that he wants to talk about more advanced topics but doesn't want to confuse everyone. Love the Video!

  • @TCreel
    @TCreel Před 8 lety

    So what I got from this is this. If, for example, if I remove the attracting force between the atoms or the temperature in the system of forming the silicon crystals the entropy increases, due to it being less likely of forming a organized strutcure? please reply

  • @stamps9k
    @stamps9k Před 9 lety

    How does entropy always increasing tie in with the Poincare recurrence time discussed in one of the Numberphile videos?

  • @MorganEarlJones
    @MorganEarlJones Před 9 lety

    Thanks for clarifying the "parameters of the parentheses" of science ;)

  • @adamh6094
    @adamh6094 Před 5 lety

    I’m a first year engineering student, and entropy is just one of those things I feel like I totally get one day, and it’s gone the next!

  • @mattmers
    @mattmers Před 9 lety

    You two should do a podcast because I could listen to you both all day

  • @Galileosays
    @Galileosays Před 9 měsíci

    I enjoyed the S=k log W where W stands for (number of) ways. In short one could say Entropy is a macrosopic property that quantifies at thermal equilibrium the number of ways energy can be distributed over the entities in a homogeneous system.

  • @doubleRprodutions
    @doubleRprodutions Před 8 lety

    I've never had a problem getting my head round entropy and I love some of these explanations. I heard one over on Veritasium where he likened a low entropic system to a single continuous low information and low entropy and then as you add 1s and 0s you add information and increase entropy, until finally the system has to much information to make sense of (white noise) and thus you have the entropic limit.
    I personally like the script analogy, but taken a step further, you have a billion page script in order and then you blow it up, but each letter of each page zips of in all different directions, if you slow the explosion down so it takes a few billion years, then the letters will fly apart and form new words, sentences and stories, until finally they all float to the floor and are at rest and at the highest entropic state.
    Probably completely misleading analogies, but they work for me :)

  • @Thetarget1
    @Thetarget1 Před 9 lety

    That was fascinating! Luckily at my university we were never taught entropy as being synonymous with disorder, but instead as a measure of the multiplicity of the system (which could sometimes be seen as disorder). I think we were saved a lot of confusion from that.

  • @ValsGym
    @ValsGym Před 9 lety +2

    I think the best way to explain entropy, is by first explaining the concept of the Gibbs Free Energy, and what it means about a system then introduce dG = dH + TdS. Because then dS can be related to its dependence on the temperature. The throw in how with the temperature and the energy flow in the system things either adopt a ordered or disordered state.
    I don't know but I will look at those papers for sure.. great topic this one

    • @stinooke
      @stinooke Před 9 lety +1

      The equation for Gibbs free energy is actually a simple derivation of the second law.The total entropy change of the universe is given by dG/T. dS in this case merely refers to the internal entropy change of the system, You really need to understand the second law and have a basic understanding of entropy before you can understand the meaning of the Gibbs function.

    • @jamez6398
      @jamez6398 Před 9 lety

      That's how it's done in chemistry at any rate...

  • @optimusimperat
    @optimusimperat Před 8 lety

    ok. can you please make a video explaining how they came up with the thermodynamic tables of substances? exactly how do they come up with the entropy values?

  • @JmanNo42
    @JmanNo42 Před 9 lety

    Interesting that the data equivalent entropy now seems to be the same as the physics "the number of ways" possible permutations?
    Was that always the case?