3:46 "S" is short for "S does not appear in the word entropy", just as "p" is short for "p does not appear in the word momentum". It's a very convenient naming scheme.
Ludwig Boltzmann, who spent much of his life studying statistical mechanics, died in 1906, by his own hand. Paul Ehrenfest, carrying on the work, died similarly in 1933. Now it is our turn to study statistical mechanics. ―David L. Goodstein, introduction to States of Matter 1975
@@CredibilityofNoOne how about after you graduate and you realize real engineers hardly ever use anything above sophomore level and are usually just changing one thing at a time until it works?
One of the first things I learned in Chem 162, after the prof told us that the ideal gas equation was about good enough for most applications, was just how loosely he meant that. Right there in the classroom, the variation from the "ideal" was causing more disruption to my values than my own ineptitude at using the tools provided.
Idk I'm not a scientist and we're not in class so I gently allowed myself to giggle when she drew a "box of gas" on the board, It was just the human thing to do. But I admire how you people just had a 5-subcomment long exchange about gas without any pun, you must have been through a lot, I respect it
@@CredibilityofNoOne Fwiw, us chemists have very different foci than chem engineers. Industrial equipment may elude us, but instead we are examined rigorously on quantum mechanics and numerical methods like "Hartree-Fock", "Correlation Interaction", "Density Field Theory." At least at my university (ELTE), knowledge of QM is a mandatory undegraduate requirement. If you go to MSc, you must have a working knowledge of Electronic Structure Theory and Molecule Dynamics to pass your final exam in Physical Chemistry.
@@CredibilityofNoOne i think education is generally trying to adapt to a population that is globally coping with lots of different inputs and to which the "common" part in "common sense" appears to get slimmer
Just reminded me of the three laws of thermodynamics from undergrad days: 1) you can't win, 2) you can't break even, and 3) you can't get out of the game.
According to Wikipedia, this statement of the laws of thermodynamics might have it's roots in an R&B song from the 70s. It's possible that this was inspired by an earlier scientific statement, but I prefer to believe in the coincidence :)
13:43 it may also be helpful to know that “eulers theorem” refers to at least a dozen different theorems in vastly different areas and that google seems to lack any regard for this
Crank theory; Leonard Euler was a fake name like Alan Smithee, that people put on their papers as an in-joke. You expect me to believe there was a whole generation where every mathematical discovery was by the same guy?
Yep the first euler theorem I knew of was the order of multiplicative elements in Z_n (as used in nt/crypto particularly RSA), then the e^(it)=cos(t)+isin(t), but will be learning the one from the video in diffeq p soon
Physics student here. The only time I have ever encountered the term "vis visa" is in the book More Heat than Light by Philip Mirowski. Among other things, it talks about the history of the concept of energy in physics. Vis visa is an old fashioned term for kinetic energy (but defined as mv^2) which Leibniz came up with. He also uses the term vis mortua (literally dead force) for potential energy. Weirdly there were all kinds of inconsistent definitions of "force" in early mechanics and the term energy didn't get introduced until way later by Thomas Young.
Joule and the 1st law of thermo is a really amazing story. The 1st law actually came after the 2nd law (which Carnot basically had in 1824). And it took a long time for the community to accept Joule's experiments showing that thermal energy and mechanical (and later electrical) work were equivalent. Part of this was because the chemists were really insistent on conservation of heat (q_in = q_out), whereas Joule implies q_in + w = q_out.
Mathematicians typically use H to represent entropy, and there's actually an explanation. In the beginning of statistical mechanics, Boltzmann used E, but Gibbs and others used η. Eventually other people started referring to Boltzmann's "E-theorem" as the "H-theorem," where the "H" is probably supposed to be a capital eta. After a while, Boltzmann gave in and started calling it his "H-theorem" too. Then, 50 years later, Claude Shannon named his concept of information-theoretic entropy after Boltzmann's H-theorem, but he didn't know it was supposed to be the Eta-theorem, because of some combination of the distance in time, the fact that Shannon was a mathematician and not a physicist, and the general trend away from Greek and Latin and toward English. So he just thought it was an H and now we're stuck with that. However, I still have no idea what Clausius's excuse for S is. As far as I can tell, he literally just wrote "Let us denote this quantity by S," and I guess that was that. (OK, fine, he *literally* literally wrote "Bezeichnen wir diese Größe mit S".) Maybe "S" stands for Shannon. Clausius wrote his paper 50 years before Shannon was born, but I don't see why that should matter.
I don't know if mathematicians do use "H" for entropy (I douubt it) but I do know just about everyone else who need to know thermodynamics uses "H" for enthalpy and "S" for entropy and "E" for energy. The lower case equiverlents are used for 'per unit mass' quantities, hence the equation h = u + Pv. But perhaps I am just not in tune with the humour of this mock-umentary.
@@ZeroPlayerGameI took thermodynamics and fluid mechanics in the same term some years ago, and man oh man, I cannot express the amount of confusion during the entire semester, especially going back and forth between the two courses. This isn't even factoring in the each professor's specific way of notating stuff or each of their "unique" penmanship xp lmao
@@chrisjohnson8666 Why do you doubt it? It's not the most surprising thing, you can ask any mathematician. You can also just check the wiki page for Shannon entropy
The effortless switching from chemistry to physics to astronomy to comedy and back in all of these videos is like a form of performance art ... I'm hooked.
It's amazing how intuitive the idea that "adding energy to a gravitational bound system slows things down" becomes from playing enough Kerbal Space Program.
This is so far past my sixth grade education level and so far outside what I thought was my areas of interest, yet here I am, eager to learn and try my damndest to understand things I will never be able to use beyond when I'm geeking out to friends. Thank you for making this more accessible and genuinely enjoyable.
I appreciate your advice of people being familiar with the ideal gas law. The NFL had a whole "cheating" scandal because no one understood that pressure in footballs change with temperature. It even got a fun "gate" name: deflategate
I disagree that it has a fun gate name. Why do some many scandals get named "something"gate? Watergate is named because it occurred in the Watergate hotel. Now so many others are named after that with no relationship too a gate of any kind.
@@indetigersscifireview4360 For the longest time I thought "Oceangate" was the name of the scandal surrounding the company that had caused the tragedy, until I found out it's actually just the name of the company.
Okay so after binge watching your entire channel, a few thoughts. 1) amazing comedic timing. I have laughed so much. Thank you. 2) I am infinitely more interested in science/data/academia than I ever thought I would be, specifically because of how you present it in an interesting/engaging way. 3) it's fine 4) you are like Jenny Nicholson levels of good at this, and while I know this is not your main thing, this channel deserves millions of subscribers. 5) that said, no pressure at all in like making a ton more content even if your channel does end up getting substantially larger.
Got a bit lost on the math (though it's cool to have it) but every single thing was worth the end and the mockumentary, particularly the guest appearance from Michio Kaku. Amazing. Love this channel.
^ To add to this, think the gravitational field near the surface of the Earth. You do work going up and down (parallel to the field), but not sideways (perpendicular to the field). Work is done when the motion happens in the direction of the force (parallel). Force in an electric field is perpendicular to the direction of motion of the charged particles generating the field-therefore, no component of force can ever be in the direction of motion, so no work is done
wow i love that you used to be able to put half a definition in latin and just expect people to get it. academia was wild in the 19th century when everyone went to the same 2 schools
You said dark matter at 9:04 and Fritz Zwicki in the same sentence and my classically conditioned brain immediately went: "Dark matter do we need it do we need it do we need it how much what is it do we need it do we need it do we need it" help
it's really great to see your channel becoming so successful! as another woman in STEM, it's nice to see so many people listen to and appreciate your work on these videos. they have been the soundtrack to my work for the past few weeks!
The virial theorem is used regularly by people running molecular dynamics simulations, as it gives a way to estimate the stress when all the atoms are wiggling around.
the only two things i took out of my thermodynamics class were: 1. enthalpy is not entropy. i don't know what it is, just that it's not entropy 2. steam is not an ideal gas, don't try to use the ideal gas law with steam
I do hope you this as a compliment, because I intend this as a compliment, but as a former high school teacher, I would like to say that you would make an _amazing_ high school physics teacher. You have this way of expressing complex ideas through relatable and interesting stories. At the school where I taught (I taught art, not science), the students who were not already math(s)-literate and nerdy about science, tended to _hate_ their physics classes. I think this is mostly because my physics teacher colleagues just taught formulas and concepts that their students needed to know in order to pass their final exams; but they didn't tell stories. They didn't nurture a love, or at the very least, an appreciation of the subject. Students just wanted to survive the class and prayed to the Lord God Above (or Vishnu or Ganesha or whomever) that they would pass the semester exam and then actively purge their brains of everything they had learned once the semester is over. Very few of them actually came away with any kind of appreciation of physics/chemistry/biology. Now, I'm sure you've taught (or perhaps are currently teaching) undergrads, and that's fine, and no doubt, you're very good-your channel is proof of this-but I bring up high school physics because high school is the time that can make or break a student's love of a subject, and for the most part, is where they determine their career path. Teachers play a critical role in this process by how they present the subject to their students. Do they share their love/passion for the subject by telling stories or do they just hand out worksheets and regurgitate the textbook? Your videos make it clear that you are passionate about astrophysics and science in general. While most of your videos are about an hour long, I don't _feel_ like I've sat through an hour-long physics lecture. There are no boring bits, but also, I don't feel overwhelmed by a flood of information. _THAT_ is why I think you'd make an excellent high school physics teacher.
Hey, I've invented a perpetual motion machine. It's so simple. It doesn't run off of fuel AT ALL. Just use your legs. I call it Pedalpetualmotion. I mean, sometimes you get tired, but I think that's just a practice thing.
When I grew up in the 80s, Nova wasn't so cringe. I've tried to watch it in the last decade and it always disappoints. Your calm (and amusing asides) are more like how it used to be, thanks for this!
I don't comment on TH-cam often, but felt compelled to just say that your videos are absolutely fantastic! Your passion for learning and science is extremely contagious and you present it all in a very well-spoken, informative and humorous way. Just top-notch stuff. Thank you for elevating the level of science communication on TH-cam, it is truly inspiring.
NOVA is what made me love science as a kid, and it will always have a special place in my heart. You're absolutely right about the ridiculous and overly dramatic way it's presented though. You were spot-on and hilarious.
Just soon after Sabine and veritasium made videos about entropy... And I was thinking about entropy and how it makes the difference between life and non-life for weeks now and suddenly everyone makes videos about entropy which makes me think about it even more, and now I am overwhelmed
Fun fact: Keira Knightley as Joan Clarke in the 2014 movie The Imitation Game also pronounces Euler [YULE-er] instead of [OY-ler]. (13:59) Mispronouncing words that you have read is sometimes called Calliope [KAL ee ope] Syndrome, which is a playful pronounciation of the name of the Muse of eloquence, Calliope [kuh LIE oh pee]. I'm sure I was not alone in reading the early Harry Potter books featuring Hermione [HER-mee-own], and only after the first movie came out realizing that the smart one of the gang is Hermione [her MY oh nee]. I am really enjoying and appreciating your videos, and hope my comments don't seem Pinkerish!
That was the best Nova I’ve ever seen … but maybe you could add a few more novas to your Nova? All I can say is thank god I’ve been binge watching Walter Lewin teaching MIT 802 classes all day or I might not have understood the roughly 1.3% of what you said like, at all! I did recognize many of the formulas as they flew by (“ooo … pretty”) so that was good for me. Even saw the 4pi denominator I was introduced to about 3 hours ago. In short: I loved this video and will probably have to watch it only 9 or 10 (hundred) more times as I work through the homework. Such awesome.
So fun fact. In information theory, entropy is not given the letter S, but instead the letter Η. So for years I was like "that also makes no sense". But I recently discovered that actually the Η is not a capital h, but a capital η (eta, for those who dont know). Which actually checks out. My mind was blown.
And just like that, my meal prep time is instantly enhanced. Also, as a mathmetician, i just thought people were being cooky and saying "oiler" and continued to say "Yuler" until a friend pulled me aside years later.
My mom's side of the family is German. So when I learned about Euler, I just took it as a matter of course. (in German, the "eu" vowel combination is pronounced like "oy")
I was a physics major in college. Never needed the Work = Force x Distance equation in anything outside the assignment of the week. It did come up later (after graduation) in relation to dictatorial bosses (Grumman Aerospace comes to mind). They'd ask have you covered any ground? They didn't care about the effort expended, since 0 distance meant 0 work, and then they refused to pay you. P.S.: I love your multicolor esthetic with a dark theme on your calculations. So comfortable on the eyes. My physics professes tended to use blaring cellophane overhead projectors with 1 KiloWatt bulbs in darkened auditoriums, plain black markers, and rapid hands to crank the slide to the next position. Please note they also didn't care about the difference in their writing scribble speed vs. the student's cognitive processing delay added to their own copying speed. An illustration of entropy increasing. Bye!
Leviathan Wakes! I'm in the fourth book of the series, awesome book. Nowadays, there are are theorems that could be called "viral" theorems....but seriously, there is no more solid branch of physics than statistical physics...it's so powerful that it stands on its own, even if the rest of physics, for some weird reason, is proven wrong. Also, if anything, the most important equation is S = k ln Omega, it encodes all the important statements in thermodynamics!
Very good and also entertaining, as always. Nitpick: PV = n R T is used more in chemistry or physics related to chemistry, while the form p = n k_B T is more frequently used in many branches of physics (here, k_B is Boltzmann's constant - named after the Austrian scientist who developed the theory of statistical dynamics / thermodynamics). Pressure rises if you put more particles "n" into your tires, or if you raise the temperature "T" in your pressure cooker.
Yay! Angela made a virial video! 😛 PS - When I was in school, I used to get entropy and enthalpy confused. I always wondered who was the sadistic SOB who made those confusing terms.
You must have won quite a lot of TA awards if you were ever a teacher’s assistant. Not only are you blazingly fast with with your equation writing, you know when to hand-wave and when to focus on the actual important part of the lesson. *chef’s kiss*
Nova was (is?) fantastic for children! It's simplicity and dramatic liberties made it brain candy for me as an 8-12 year old. I wouldn't love math and science the way I do now, even though I've personally outgrown Nova.
Hi, I'm nobody from nowhere and usually just a lurker, but I feel compelled to post that I just found your channel and I love it. I couldn't science my way out of a paper bag but I find your content easily digestible, entertaining and informative. I hope you have a wonderful day.
S could be a reference to Sadi Carnot. Claussius studied Carnots ideal heat engine and his corrections to Carnot's model made Claussius' name around 1850. By studying that ideal heat engine he also discovered a quantity (entropy) which is conserved in the ideal case, but not in real engines
I don’t wanna overdo it here, but, ahem…. I think you must be a deeply precious individual and even though I’ve never met you I’m just positive that the world is better with you in it. Aaaaand I want you to know that I’ve been watching all 30 seconds of the ads that pop up on your videos so as to maximize my viewing potential for your channel. Thank you for the amazing content!!!
the joy you had describing thermo dynamics made up for me trying to keep up in astrophysics... it sounded more like you were describing change of state then temperature for your negative scale ...thank you for taking the time to film this
You've officialy become the youtuber I'm most excited to get notifications from. Also as a fellow dark matter person, your last video has been so helpful in learning how to explain what I do to people!
As a clacissist/linguist/amateur historical linguist (a very different field from linguistics), I'm actually really digging Clausius's words. And will be adding "the vis viva is equal to its virial" to my random fun phrases lost.
You asked if anybody uses virial theorem in their work. I used it to develop HECSS which is an alternative to molecular dynamics as a configuration generator for interactions modelling in solid state. You can find it on scipost physics if you are interested.
Wait a second, I've read a few of your papers when I was obsessed with phonons and dft. What a tiny world it is to see such a respected scientist here (and a fellow pole to boot!).
@@MargoTheNerd Thanks. Nice to meet you. When you write papers, you really don't know if they have any audience. Citation count is not really a measure - people often put references without reading the paper, just to acknowledge the body of work in the field. The feeling is strangely satisfying ;)
@@pjochym Oh, they are read and appreciated - although I had to blatantly steal at least one of them from sci-hub (PhysRev B being beyond my access, unfortunately). Which I only admit after finding out you are a proponent of free knowledgeafter doing some moderate stalking to prevent mis-identification (and to find out what exactly is HECCS and whether the name has relation to a certain joke I've heard from another physicist ;) Now I wonder what was there on the nanoalloy website - do you plan on updating it one day (it's currently down,as you probably are aware)? It would be great to have a hub to share knowledge and ideas about the subject - I've ran into plenty curious, intelligent young people to whom ability to "brainstorm" with accomplished scientists such as yourself could very well make or break their interest in physics. And with the way physics is taught in our country, I think there's immense value in encouraging their interest, curiosity and talent to offset that. Anyway, enough fan-girling, apologies for the thievery :)
OMG! You are hilarious. I've never had so much fun not comprehending half of the math in a 30 minute lecture. I should have read the section before the class. And yet, I got the point, and quite a big reveal it was.
I'm partial to PV = NkT myself, but that's probably stat mech rubbing off on me. Definitely didn't understand entropy until then, heck couldn't even keep it straight from enthalpy before that course. Oddly, I never heard of the gravothermal catastrophe - Hot bods get hotter!
Encountering Euler written before hearing him mentioned by someone else is super commendable and shows a ton of initiative and enthusiasm for education!
You have become my favorite TH-camr in the shortest span of time. It's been awhile since I don't get excited about a new video from one of my subscriptions. Thanks for making TH-cam pleasent again :)
Ok, I just have to ask cause you have thrown a pile o' books in a several episodes and started this one with one of my favorites of all time. Was wondering if you had a book list anywhere of your personal favs? I've read most of what you have had on screen so far I believe, but want to know if I am missing some gems :D
You are legit my fav youtuber. I havent even gone to school yet (almost 30 and finally attempting), but ive been binging your stuff bc its so entertaining
I had a thermodynamics teacher who could barely speak English. He didn't speak it well enough for us to ask questions. Thank goodness for the text book!
"the mean vis viva of the system is equal to its virial" is the new "mitochondria is the powerhouse of the cell" in my brain now thank you for the new brain worm that I will never be able to dislodge
I feel so sorry for all those people that never had latin and greek in school... My 8 years of it were hell... But it is so useful...like for everything...
i love the ideal gas law. when i was 15 i maintained the atmospherics simulation subsystem for an open source game set on a space station. i got to know PV=nRT very well over the years handling those simulations
The delivery of the final "Specific science persona we're dragging for good reason" example absolutely made my day. That's got to be the deadest pan I've seen from a physicist, ever (so far).
German speaking people will probably have an easier time with that. Because in German, the "eu" vowel combination is typically pronounced like "oy". Also, I think Euler was Swiss. The German language is pretty common in Switzerland.
Love that you started this video reading Leviathan Wakes. The Expanse was one of my most favorite TV sci-fi shows ever, starting from the 1960s forward.
OMG that last part of the video was great! I love the particular flavor that you put into your videos, it makes your content so unique and fun. Also, as a non-physicist I didn't understand most of the video, but I had no idea about these concepts and the gravothermal catastrophe in particular is so interesting and counterintuitive. Keep up the good work!
My AP Chem teacher made us learn a song about it. 20 years later I can still sing the whole thing. We sang it at our high school reunion. No, it’s ok. i’m fine.
Oh my god having Angela explain the virial theorem as I go to sleep was not something I thought I would want in life. If having a parasocial attachment is wrong then I don't want to be right.
I'm a physics master student doing md simulations and I have recently come across the virial to calculate the stress tensor and viscosity of the system. The virial stress is just the sum of all r_i F_i. Common simulation packages like laamps also use it.
Every now and then you should throw in little maths problems like 10-4 or 2+7 so I can follow along and feel good about myself managing to keep up.
Agreed
Feel smart for the rest of us man
I should study Italian opera, lots of similar names, years...this is my Virial! Maybe German opera? Der Freischütz? i
Very much agree!
3:46 "S" is short for "S does not appear in the word entropy", just as "p" is short for "p does not appear in the word momentum". It's a very convenient naming scheme.
c as in speed of ligcht
LOL
@@georgelionon9050celerity being the "speed" of a wave, c is very aptly named
@@Redfox0928 celewhat?
p is because momentum is also called imPulse
Ludwig Boltzmann, who spent much of his life studying statistical mechanics, died in 1906, by his own hand. Paul Ehrenfest, carrying on the work, died similarly in 1933. Now it is our turn to study statistical mechanics.
―David L. Goodstein, introduction to States of Matter 1975
Love this quote, and love seeing you here.
simultaneously didn't expect to see you reply here, and also not surprised either lol
:D
Not today, Satan.
@@andrewfleenor7459 What's the hurry, right? :D
As a chemical engineering student, nothing is more devastating than when the gas is not ideal and you can't use ideal gas equation
@@CredibilityofNoOne how about after you graduate and you realize real engineers hardly ever use anything above sophomore level and are usually just changing one thing at a time until it works?
One of the first things I learned in Chem 162, after the prof told us that the ideal gas equation was about good enough for most applications, was just how loosely he meant that. Right there in the classroom, the variation from the "ideal" was causing more disruption to my values than my own ineptitude at using the tools provided.
Idk I'm not a scientist and we're not in class so I gently allowed myself to giggle when she drew a "box of gas" on the board, It was just the human thing to do. But I admire how you people just had a 5-subcomment long exchange about gas without any pun, you must have been through a lot, I respect it
@@CredibilityofNoOne Fwiw, us chemists have very different foci than chem engineers. Industrial equipment may elude us, but instead we are examined rigorously on quantum mechanics and numerical methods like "Hartree-Fock", "Correlation Interaction", "Density Field Theory."
At least at my university (ELTE), knowledge of QM is a mandatory undegraduate requirement. If you go to MSc, you must have a working knowledge of Electronic Structure Theory and Molecule Dynamics to pass your final exam in Physical Chemistry.
@@CredibilityofNoOne i think education is generally trying to adapt to a population that is globally coping with lots of different inputs and to which the "common" part in "common sense" appears to get slimmer
Just reminded me of the three laws of thermodynamics from undergrad days: 1) you can't win, 2) you can't break even, and 3) you can't get out of the game.
Unless you're Julie Mao and then: 4) you can't take the Razorback
According to Wikipedia, this statement of the laws of thermodynamics might have it's roots in an R&B song from the 70s. It's possible that this was inspired by an earlier scientific statement, but I prefer to believe in the coincidence :)
I just lost the game :(
That's a seriously funny joke! 😂
You can leave the game, it's just a... very unsavory option for most people.
13:43 it may also be helpful to know that “eulers theorem” refers to at least a dozen different theorems in vastly different areas and that google seems to lack any regard for this
...I actually had the wrong theorem in the screen shot and had to export the video again after correcting it.
They say that everything in math is named after the second person to discover it, cuz the first was always Euler
Crank theory; Leonard Euler was a fake name like Alan Smithee, that people put on their papers as an in-joke. You expect me to believe there was a whole generation where every mathematical discovery was by the same guy?
@@octopeople Euler was the Nicolas Bourbaki of his time (or their time?)
Yep the first euler theorem I knew of was the order of multiplicative elements in Z_n (as used in nt/crypto particularly RSA), then the e^(it)=cos(t)+isin(t), but will be learning the one from the video in diffeq p soon
Physics student here. The only time I have ever encountered the term "vis visa" is in the book More Heat than Light by Philip Mirowski. Among other things, it talks about the history of the concept of energy in physics. Vis visa is an old fashioned term for kinetic energy (but defined as mv^2) which Leibniz came up with. He also uses the term vis mortua (literally dead force) for potential energy. Weirdly there were all kinds of inconsistent definitions of "force" in early mechanics and the term energy didn't get introduced until way later by Thomas Young.
@@Alfred-Neuman Never met anyone with that problem.
@@Alfred-Neuman they don't think about it but they do all quietly chant PV=nRT three times when they climax.
Joule and the 1st law of thermo is a really amazing story. The 1st law actually came after the 2nd law (which Carnot basically had in 1824). And it took a long time for the community to accept Joule's experiments showing that thermal energy and mechanical (and later electrical) work were equivalent. Part of this was because the chemists were really insistent on conservation of heat (q_in = q_out), whereas Joule implies q_in + w = q_out.
As an engineering grad I only remember the term 'vis visa' from when I was buying required texts at the school bookstore.
@@Alfred-Neuman No. Kinda weird dude.
Mathematicians typically use H to represent entropy, and there's actually an explanation. In the beginning of statistical mechanics, Boltzmann used E, but Gibbs and others used η. Eventually other people started referring to Boltzmann's "E-theorem" as the "H-theorem," where the "H" is probably supposed to be a capital eta. After a while, Boltzmann gave in and started calling it his "H-theorem" too. Then, 50 years later, Claude Shannon named his concept of information-theoretic entropy after Boltzmann's H-theorem, but he didn't know it was supposed to be the Eta-theorem, because of some combination of the distance in time, the fact that Shannon was a mathematician and not a physicist, and the general trend away from Greek and Latin and toward English. So he just thought it was an H and now we're stuck with that.
However, I still have no idea what Clausius's excuse for S is. As far as I can tell, he literally just wrote "Let us denote this quantity by S," and I guess that was that. (OK, fine, he *literally* literally wrote "Bezeichnen wir diese Größe mit S".)
Maybe "S" stands for Shannon. Clausius wrote his paper 50 years before Shannon was born, but I don't see why that should matter.
S for "see if I care"
I don't know if mathematicians do use "H" for entropy (I douubt it) but I do know just about everyone else who need to know thermodynamics uses "H" for enthalpy and "S" for entropy and "E" for energy. The lower case equiverlents are used for 'per unit mass' quantities, hence the equation h = u + Pv. But perhaps I am just not in tune with the humour of this mock-umentary.
@@chrisjohnson8666 and yet fluid dynamics uses lowercase p for pressure... nomenclature confusions are always aplenty
@@ZeroPlayerGameI took thermodynamics and fluid mechanics in the same term some years ago, and man oh man, I cannot express the amount of confusion during the entire semester, especially going back and forth between the two courses. This isn't even factoring in the each professor's specific way of notating stuff or each of their "unique" penmanship xp lmao
@@chrisjohnson8666 Why do you doubt it? It's not the most surprising thing, you can ask any mathematician. You can also just check the wiki page for Shannon entropy
The effortless switching from chemistry to physics to astronomy to comedy and back in all of these videos is like a form of performance art ... I'm hooked.
One of my favorite new science education channels, I want a collab with Hank Green
It's amazing how intuitive the idea that "adding energy to a gravitational bound system slows things down" becomes from playing enough Kerbal Space Program.
Kerbal space program should be in every school
This is so far past my sixth grade education level and so far outside what I thought was my areas of interest, yet here I am, eager to learn and try my damndest to understand things I will never be able to use beyond when I'm geeking out to friends. Thank you for making this more accessible and genuinely enjoyable.
I appreciate your advice of people being familiar with the ideal gas law. The NFL had a whole "cheating" scandal because no one understood that pressure in footballs change with temperature. It even got a fun "gate" name: deflategate
Tom Brady was suspended for four games and the Patriots fined one million dollars.
we still won the superbowl that year.
Aren't the footballs kept in temperature controlled containers on the sidelines?
I'm pretty sure they well knew that pressure goes down when its cold. Certainly by the time the investigation was done, that was taken into account.
I disagree that it has a fun gate name. Why do some many scandals get named "something"gate? Watergate is named because it occurred in the Watergate hotel. Now so many others are named after that with no relationship too a gate of any kind.
@@indetigersscifireview4360 For the longest time I thought "Oceangate" was the name of the scandal surrounding the company that had caused the tragedy, until I found out it's actually just the name of the company.
Okay so after binge watching your entire channel, a few thoughts.
1) amazing comedic timing. I have laughed so much. Thank you.
2) I am infinitely more interested in science/data/academia than I ever thought I would be, specifically because of how you present it in an interesting/engaging way.
3) it's fine
4) you are like Jenny Nicholson levels of good at this, and while I know this is not your main thing, this channel deserves millions of subscribers.
5) that said, no pressure at all in like making a ton more content even if your channel does end up getting substantially larger.
I agree. Make the video for you, not us. I like the style. It’s fine.
And you're providing people with valuable information like "If you want to look it up, this is how you spell Euler". It's fine. We live in a society.
i was thinking about the exact same comparison to Jenny Nichelson, very similar vibes
@@scottsanford1451 If you've ever studied German (even a little bit) and you remember Euler was German, it starts to make perfect sense.
It’s amazing how prolific you’ve been recently.
I'm old now but if I was young again I'd be in love for her mind. Well actually even her vast beauty, she is gorgeous.
@@ernestwhite2505lust isnt love. I'm young, and quote Forrest Gump.. "i know what love is."
"Genius hacker MIT". I love that one.
@@ernestwhite2505no need to be creepy online my guy.
@@ernestwhite2505 luckily, simping is not creepy at all.
32:49 Michio Kaku: "... agony, agony..."
This channel is developing some lore.
Lore: The Kaku Agony
Got a bit lost on the math (though it's cool to have it) but every single thing was worth the end and the mockumentary, particularly the guest appearance from Michio Kaku. Amazing. Love this channel.
Agony
Clausius really just got sick of people asking why the sky was blue and wrote his PHD thesis on it and I can respect this.
And YES to 'magnets do no work.' I've always had this intuition, but would love to hear a real explanation.
Differential work is F dot ds. But in a magnetic field B, F is always perpendicular to movement (F = qv x B)
^ To add to this, think the gravitational field near the surface of the Earth. You do work going up and down (parallel to the field), but not sideways (perpendicular to the field). Work is done when the motion happens in the direction of the force (parallel). Force in an electric field is perpendicular to the direction of motion of the charged particles generating the field-therefore, no component of force can ever be in the direction of motion, so no work is done
Tried to correct that typo, but the algorithm doesn't like me, again.
Scratch that... I had a full reply that posted, but also had a typo. You're broken, youtube. Get your $#17 together!
"Captain Disillusion" did a phenomenal on so called "free energy devices" / "magnets do not work that way".
wow i love that you used to be able to put half a definition in latin and just expect people to get it. academia was wild in the 19th century when everyone went to the same 2 schools
Sometimes you'd also just get metaphors and they weren't necessarily always obvious.
You said dark matter at 9:04 and Fritz Zwicki in the same sentence and my classically conditioned brain immediately went: "Dark matter do we need it do we need it do we need it how much what is it do we need it do we need it do we need it" help
I've had that dang clip stuck in my head for like two weeks now and I don't know whether to be angry or grateful.
I posit dark matter is camouflaged matter: hiding in plain sight. Or just shy.
The Michio “agony” part made me actually laugh out loud
it's really great to see your channel becoming so successful! as another woman in STEM, it's nice to see so many people listen to and appreciate your work on these videos. they have been the soundtrack to my work for the past few weeks!
The virial theorem is used regularly by people running molecular dynamics simulations, as it gives a way to estimate the stress when all the atoms are wiggling around.
you're damn right it's fine. your ability to be genuine is so refreshing for this platform.
*grabs popcorn and the cat* so excited! a new video by my favorite scientist just dropped! 😀
My favorite PhD Kansan!
Made my day as well
the only two things i took out of my thermodynamics class were:
1. enthalpy is not entropy. i don't know what it is, just that it's not entropy
2. steam is not an ideal gas, don't try to use the ideal gas law with steam
I do hope you this as a compliment, because I intend this as a compliment, but as a former high school teacher, I would like to say that you would make an _amazing_ high school physics teacher. You have this way of expressing complex ideas through relatable and interesting stories. At the school where I taught (I taught art, not science), the students who were not already math(s)-literate and nerdy about science, tended to _hate_ their physics classes. I think this is mostly because my physics teacher colleagues just taught formulas and concepts that their students needed to know in order to pass their final exams; but they didn't tell stories. They didn't nurture a love, or at the very least, an appreciation of the subject. Students just wanted to survive the class and prayed to the Lord God Above (or Vishnu or Ganesha or whomever) that they would pass the semester exam and then actively purge their brains of everything they had learned once the semester is over. Very few of them actually came away with any kind of appreciation of physics/chemistry/biology.
Now, I'm sure you've taught (or perhaps are currently teaching) undergrads, and that's fine, and no doubt, you're very good-your channel is proof of this-but I bring up high school physics because high school is the time that can make or break a student's love of a subject, and for the most part, is where they determine their career path. Teachers play a critical role in this process by how they present the subject to their students. Do they share their love/passion for the subject by telling stories or do they just hand out worksheets and regurgitate the textbook? Your videos make it clear that you are passionate about astrophysics and science in general. While most of your videos are about an hour long, I don't _feel_ like I've sat through an hour-long physics lecture. There are no boring bits, but also, I don't feel overwhelmed by a flood of information. _THAT_ is why I think you'd make an excellent high school physics teacher.
Hey, I've invented a perpetual motion machine. It's so simple. It doesn't run off of fuel AT ALL. Just use your legs. I call it Pedalpetualmotion. I mean, sometimes you get tired, but I think that's just a practice thing.
You still breathe while resting which is a motion.
I'm a stoned software engineer and you made physics far more intuitive than every prof I've ever had.
Your Michio Kaku impression at the end really cracked me up !!!!!! love your videos so much
When I grew up in the 80s, Nova wasn't so cringe. I've tried to watch it in the last decade and it always disappoints. Your calm (and amusing asides) are more like how it used to be, thanks for this!
I don't comment on TH-cam often, but felt compelled to just say that your videos are absolutely fantastic!
Your passion for learning and science is extremely contagious and you present it all in a very well-spoken, informative and humorous way. Just top-notch stuff.
Thank you for elevating the level of science communication on TH-cam, it is truly inspiring.
"this paper is shockingly readable"
"the mean via viva of a system is equal to its virial"
I'd enjoy a 'magnets do no work' video.
Also - "The mean vis viva of a system is equal to its virial" sounds like a line from My Fair Lady.
NOVA is what made me love science as a kid, and it will always have a special place in my heart. You're absolutely right about the ridiculous and overly dramatic way it's presented though. You were spot-on and hilarious.
Just soon after Sabine and veritasium made videos about entropy...
And I was thinking about entropy and how it makes the difference between life and non-life for weeks now and suddenly everyone makes videos about entropy which makes me think about it even more, and now I am overwhelmed
That's entropy for you
It's the entropo-youtubal catastrophe! It will continue until every video on youtube is about entropy.
Fun fact: Keira Knightley as Joan Clarke in the 2014 movie The Imitation Game also pronounces Euler [YULE-er] instead of [OY-ler]. (13:59) Mispronouncing words that you have read is sometimes called Calliope [KAL ee ope] Syndrome, which is a playful pronounciation of the name of the Muse of eloquence, Calliope [kuh LIE oh pee]. I'm sure I was not alone in reading the early Harry Potter books featuring Hermione [HER-mee-own], and only after the first movie came out realizing that the smart one of the gang is Hermione [her MY oh nee]. I am really enjoying and appreciating your videos, and hope my comments don't seem Pinkerish!
That was the best Nova I’ve ever seen … but maybe you could add a few more novas to your Nova?
All I can say is thank god I’ve been binge watching Walter Lewin teaching MIT 802 classes all day or I might not have understood the roughly 1.3% of what you said like, at all!
I did recognize many of the formulas as they flew by (“ooo … pretty”) so that was good for me. Even saw the 4pi denominator I was introduced to about 3 hours ago.
In short: I loved this video and will probably have to watch it only 9 or 10 (hundred) more times as I work through the homework.
Such awesome.
So fun fact. In information theory, entropy is not given the letter S, but instead the letter Η. So for years I was like "that also makes no sense". But I recently discovered that actually the Η is not a capital h, but a capital η (eta, for those who dont know). Which actually checks out. My mind was blown.
For real, a video titled "Magnets: How they do no work" could kill it in the algorithm.
I just came across your channel... OMG you are such a dork! Please never stop making these!
And just like that, my meal prep time is instantly enhanced.
Also, as a mathmetician, i just thought people were being cooky and saying "oiler" and continued to say "Yuler" until a friend pulled me aside years later.
I had a professor use 'Yuler (long ago now)', I legit had to check if this was some extremely good trolling mid-video.
Whelp
There's dozens of us.
My mom's side of the family is German. So when I learned about Euler, I just took it as a matter of course. (in German, the "eu" vowel combination is pronounced like "oy")
I was a physics major in college. Never needed the Work = Force x Distance equation in anything outside the assignment of the week. It did come up later (after graduation) in relation to dictatorial bosses (Grumman Aerospace comes to mind). They'd ask have you covered any ground? They didn't care about the effort expended, since 0 distance meant 0 work, and then they refused to pay you. P.S.: I love your multicolor esthetic with a dark theme on your calculations. So comfortable on the eyes. My physics professes tended to use blaring cellophane overhead projectors with 1 KiloWatt bulbs in darkened auditoriums, plain black markers, and rapid hands to crank the slide to the next position. Please note they also didn't care about the difference in their writing scribble speed vs. the student's cognitive processing delay added to their own copying speed. An illustration of entropy increasing. Bye!
Leviathan Wakes! I'm in the fourth book of the series, awesome book. Nowadays, there are are theorems that could be called "viral" theorems....but seriously, there is no more solid branch of physics than statistical physics...it's so powerful that it stands on its own, even if the rest of physics, for some weird reason, is proven wrong.
Also, if anything, the most important equation is S = k ln Omega, it encodes all the important statements in thermodynamics!
Very good and also entertaining, as always. Nitpick: PV = n R T is used more in chemistry or physics related to chemistry, while the form p = n k_B T is more frequently used in many branches of physics (here, k_B is Boltzmann's constant - named after the Austrian scientist who developed the theory of statistical dynamics / thermodynamics). Pressure rises if you put more particles "n" into your tires, or if you raise the temperature "T" in your pressure cooker.
Yay! Angela made a virial video! 😛
PS - When I was in school, I used to get entropy and enthalpy confused. I always wondered who was the sadistic SOB who made those confusing terms.
You must have won quite a lot of TA awards if you were ever a teacher’s assistant. Not only are you blazingly fast with with your equation writing, you know when to hand-wave and when to focus on the actual important part of the lesson. *chef’s kiss*
“orphans in the orphan-crushing machine” 😂
You have a delightfully veiled deadpan delivery. Best science comedy on TH-cam.
Nova was (is?) fantastic for children! It's simplicity and dramatic liberties made it brain candy for me as an 8-12 year old. I wouldn't love math and science the way I do now, even though I've personally outgrown Nova.
Hi, I'm nobody from nowhere and usually just a lurker, but I feel compelled to post that I just found your channel and I love it. I couldn't science my way out of a paper bag but I find your content easily digestible, entertaining and informative. I hope you have a wonderful day.
S could be a reference to Sadi Carnot. Claussius studied Carnots ideal heat engine and his corrections to Carnot's model made Claussius' name around 1850. By studying that ideal heat engine he also discovered a quantity (entropy) which is conserved in the ideal case, but not in real engines
I don’t wanna overdo it here, but, ahem….
I think you must be a deeply precious individual and even though I’ve never met you I’m just positive that the world is better with you in it.
Aaaaand I want you to know that I’ve been watching all 30 seconds of the ads that pop up on your videos so as to maximize my viewing potential for your channel.
Thank you for the amazing content!!!
It makes me so happy to see your channel growing. Can't wait to listen to this one at work!
the joy you had describing thermo dynamics made up for me trying to keep up in astrophysics... it sounded more like you were describing change of state then temperature for your negative scale ...thank you for taking the time to film this
You've officialy become the youtuber I'm most excited to get notifications from. Also as a fellow dark matter person, your last video has been so helpful in learning how to explain what I do to people!
mispronouncing things should really be a kind of flex because it means you stuck with it and pulled through with nobody to talk it over with
Great video Angela! I've been interested in astrophysics for years and never had the viral theorem explained so clearly. Thank you!
As a clacissist/linguist/amateur historical linguist (a very different field from linguistics), I'm actually really digging Clausius's words. And will be adding "the vis viva is equal to its virial" to my random fun phrases lost.
michio kaku killed me, how does it feel like being the funniest person alive
I've found yourt channel about half a week ago and now I watch your video as it goes online for the first time. So thought provoking
You asked if anybody uses virial theorem in their work. I used it to develop HECSS which is an alternative to molecular dynamics as a configuration generator for interactions modelling in solid state. You can find it on scipost physics if you are interested.
Wait a second, I've read a few of your papers when I was obsessed with phonons and dft. What a tiny world it is to see such a respected scientist here (and a fellow pole to boot!).
@@MargoTheNerd Thanks. Nice to meet you. When you write papers, you really don't know if they have any audience. Citation count is not really a measure - people often put references without reading the paper, just to acknowledge the body of work in the field. The feeling is strangely satisfying ;)
@@pjochym Oh, they are read and appreciated - although I had to blatantly steal at least one of them from sci-hub (PhysRev B being beyond my access, unfortunately). Which I only admit after finding out you are a proponent of free knowledgeafter doing some moderate stalking to prevent mis-identification (and to find out what exactly is HECCS and whether the name has relation to a certain joke I've heard from another physicist ;)
Now I wonder what was there on the nanoalloy website - do you plan on updating it one day (it's currently down,as you probably are aware)? It would be great to have a hub to share knowledge and ideas about the subject - I've ran into plenty curious, intelligent young people to whom ability to "brainstorm" with accomplished scientists such as yourself could very well make or break their interest in physics. And with the way physics is taught in our country, I think there's immense value in encouraging their interest, curiosity and talent to offset that.
Anyway, enough fan-girling, apologies for the thievery :)
over the past week, this has become my favourite channel on TH-cam. Thank you for existing, human
This video did such a good job at spreading around it went virial.
OMG! You are hilarious. I've never had so much fun not comprehending half of the math in a 30 minute lecture. I should have read the section before the class. And yet, I got the point, and quite a big reveal it was.
I'm partial to PV = NkT myself, but that's probably stat mech rubbing off on me. Definitely didn't understand entropy until then, heck couldn't even keep it straight from enthalpy before that course.
Oddly, I never heard of the gravothermal catastrophe - Hot bods get hotter!
You actually make one of the most interesting science videos on the internet.
I loved this one.
Encountering Euler written before hearing him mentioned by someone else is super commendable and shows a ton of initiative and enthusiasm for education!
You have become my favorite TH-camr in the shortest span of time. It's been awhile since I don't get excited about a new video from one of my subscriptions. Thanks for making TH-cam pleasent again :)
I just discovered your channel and this is quickly becoming one of my favorites! You are so awesome, inspiring, and entertaining!
gravothermal catastrophe is the coolest pair of words i've ever heard. you have my full attention for 33:51.
Ok, I just have to ask cause you have thrown a pile o' books in a several episodes and started this one with one of my favorites of all time. Was wondering if you had a book list anywhere of your personal favs? I've read most of what you have had on screen so far I believe, but want to know if I am missing some gems :D
1:55 This is the best explanation for the rising interest in thermo ever!
I’m a biochem major and you inspire me to be a biophysics major!! 😭😭
You are legit my fav youtuber. I havent even gone to school yet (almost 30 and finally attempting), but ive been binging your stuff bc its so entertaining
This was super educational, thank you a ton! I love your videos, but this one is particularly great
I had a thermodynamics teacher who could barely speak English. He didn't speak it well enough for us to ask questions. Thank goodness for the text book!
acollierastro is hilarious, and incredibly informative.
Sometimes I hate the TH-cam algorithm, but not tonight. You just got another professional nerd as a subscriber.
I took my pet rock to the rock doctor and was told I had to exercise it more because it was too sedimentary...
Another great video, thank you!
The last part..very relatable, at this date. Agony, agony..and wait is all we can do.
Love your work ❤
"the mean vis viva of the system is equal to its virial" is the new "mitochondria is the powerhouse of the cell" in my brain now
thank you for the new brain worm that I will never be able to dislodge
or should that be “the vis viva of the system is equal vis-a-vis its virial”? This video was so much fun for me …
A monad is a monoid in the category of endofunctors.
@@fissure256 as a disciple of Alonzo Church this comment made me unreasonably happy
No idea what's happening in the math parts, but your explanations of the concepts and ideas allows me to follow along well enough!
I feel so sorry for all those people that never had latin and greek in school... My 8 years of it were hell... But it is so useful...like for everything...
They suffer from ἀγνῶσις
I am jealous of your classical education.
I'm just gonna say that the thumbnail is a banger and a work of art
26:10 jokes on you, I couldn't follow any of the math yet still watched the whole thing 😫
Me too. 😎
Yeah, you're not the only one. 😊
i love the ideal gas law. when i was 15 i maintained the atmospherics simulation subsystem for an open source game set on a space station. i got to know PV=nRT very well over the years handling those simulations
I'm just gonna go out on a limb and guess that was SS13?
@@Nerdule yup! I was a maintainer for tgstation for years. I still keep up with the current atmos maintainer
Love your content! Keep it up! ❤
I always love the way you talk and present. It’s like funny and amusing without going “full comedy.”
Yeahhhhh, was just looking for something to fold laundry to! Thank you physics mommy!!!!
The delivery of the final "Specific science persona we're dragging for good reason" example absolutely made my day.
That's got to be the deadest pan I've seen from a physicist, ever (so far).
I was a mathematics major in college, and at 51 years old, I just learned how to pronounce Euler this year.
I like how you can see me pause before I say 'Oiler' because in my head it's still 'Yuler'
German speaking people will probably have an easier time with that. Because in German, the "eu" vowel combination is typically pronounced like "oy". Also, I think Euler was Swiss. The German language is pretty common in Switzerland.
I was legit today yrs old, etc
Love that you started this video reading Leviathan Wakes. The Expanse was one of my most favorite TV sci-fi shows ever, starting from the 1960s forward.
Perfect content, as always
OMG that last part of the video was great! I love the particular flavor that you put into your videos, it makes your content so unique and fun. Also, as a non-physicist I didn't understand most of the video, but I had no idea about these concepts and the gravothermal catastrophe in particular is so interesting and counterintuitive.
Keep up the good work!
'...Prussia, which doesn't exist anymore'. Entropy strikes again.
Your hate for Michio Kaku is my utter enjoyment.
Loved the PBS recreation. 😂😂
PV = nRT is probably the only thing I remember from AP Chem.
Also despite knowing how Euler is pronounced I always forget when im speaking 😭
My AP Chem teacher made us learn a song about it. 20 years later I can still sing the whole thing.
We sang it at our high school reunion.
No, it’s ok. i’m fine.
@@joed180okay, but like, you can't just drop that information on us here, and NOT give us the lyrics to the song 😂💀
Oh my god having Angela explain the virial theorem as I go to sleep was not something I thought I would want in life. If having a parasocial attachment is wrong then I don't want to be right.
It's like a bowling ball. Agony. Agony. Just wait.
I'm a physics master student doing md simulations and I have recently come across the virial to calculate the stress tensor and viscosity of the system. The virial stress is just the sum of all r_i F_i. Common simulation packages like laamps also use it.
*there is also a kinetic term in the stress tensor calculation