The best and most underrated science channel, hands down. This channel doesn't need huge explanation, tons of formulas and images. A simple sentences and simple images, so a 10 year old can understand it, which means he has mastered it to incredible degree. If there were more physics teachers like this guy, I am sure that there will be more people interested in physics. Nothing I can say more, keep up the good work and stay safe mate, you are a diamond.
@RAYfighter Hi, I watch PBS Space Time and Arvin Ash too, they are good and I learn much things from them, but ScienceClic makes things look so easy just with simple sentences and without unnecessary or too deep things, of course this is my opinion and nobody should be engaged with it.
The explanations are phenomenal and fascinating. But Maybe the channel could be more successful if it was more personable? Almost all other channels I watch have a talking head with an interesting personality that makes the videos feel a little more human
Your ability to break down complicated subjects so they are easy to understand is remarkable! Your teaching abilities are on par with Richard Feynman himself! Thank you so much and keep up the great work!
This is what I’ve been saying. I watched one video on black holes and it was like unlocking a door. I spent the next week figuring out everything I could about special and general relativity, Lorentz transformations, time dilation, all that stuff. I’m not claiming that it’s made me an expert of any of these things, but I can at least say it’s helped make the universe feel a lot less sad and mysterious.
Truly the best. And there is amazing content out there by pbs spacetime and Sean Carrol. But the succinct explanations and visuals make this channel the best. Aren't these same traits what made Feynman such a legend? At the least 3brown1blue level.
i dont know how many people would read this, im 2007 kid from india, gonna enter class 12th in few months. a year or 1.5yrs ago i was lucky enough one day this channels that black hole video came into my lockscreen wallpapers and i started to watch it and i fell in love with this channel........ was at class 9th end or starting 10th when i got to know about this channel. now im gonna finish 11 , i watched every video of this channel.............. i couldnt understand topics then but now i could understand way more after i read thermodynamics............. have watched ever video atleast twice.thank you sir i really have lots of respect for you...........
Thank you for another amazing video. Every single video I watch is another "ohhhhhh now I get it" moment, even when I go in thinking I have a grasp of the concept!
This is incredibly good explanation. Entropy was so strange concept to grasp.This style of education will speed up human evolution. We are so lucky to have this easy access to knowledge.
Your channel has sparked a newfound curiousity for science, I love it ! Now rather than Internet drama, I often get recommendations about the unusual science concepts I never heard before and I'm glad that for once im not consuming junk content
This might be the best (or at least most intuitive) explanation of entropy. Literally all other RU-vid channels just say that entropy is a measure of disorder without explaining how to measure disorder. I mean, there is no disorder-o-meter. But here the "measure of disorder" was explained as the probability of a family of similar arrangements. Great video :)
It seems as though this explanation presupposes some meaningful notion of familiarity and disfamiliarity on the level of emergent objects (like apples). We can only notice that some arrangements of fundamental particles are arranged 'apple-wise' if the emergent property of 'being an apple' is already a distinguished state (i.e. a 'non-random' state). But seemingly, in asking about the nature of entropy we're really wanting to ask about the nature of all things in our universe, not just those for which there is a predefined meaning to us. So our explanation requires more explaining. Carlo Rovelli gave an interesting talk (on YT) to the Royal Institute on 'The Physics and Philosophy of Time', where he pointed out that if we had an arrangement of blue and red balls in a box, and separated them by colour (blue on the left, red on the right, say), the box would seem to have low-entropy. But if we became sensitive to minute variations in size, the box of balls would in fact 'all of a sudden' look extremely homogenous (given we only sorted by colour, and not by size; they are 'sorted' with respect to colour, but 'unsorted' with respect to size). It seems to me as though the idea of entropy requires an additional point of reference to be meaningful. I am yet to have this fully click for me (though this channel surely explained more than most others!).
@@TheParadoxOfParadox That is certainly an interesting detail I haven't yet thought about. The thing is we have multiple rigorous definitions of entropy, which are independent of our perception or whether we give names to some groups of arrangements and not to others. You can blindly apply those definitions without having to know why they are defined the way they are. The problem is intuitively explaining what those definitions mean. And when using the probability of groups of arrangements as the intuition of what entropy is, it is certainly easier to imagine an apple being a less likely arrangement of particles than a homogeneous cloud of particles. But we don't have to use an apple for this comparison. We could instead talk about abstract density distributions of the cloud of particles. Density distributions with spikes or with two or more regions of different densities are intuitively less likely than a constant density distribution, because the former always evolves into the latter. Now we have an intuitive (to me) picture of entropy that is independent of our perception and whether we give a name to certain arrangements. We can even go one step further and declare two distributions "similar", if their difference is sufficiently small. How small? Well, that will depend on what kinds of distributions we want to distinguish (e.g. apples and homogeneous clouds).
Part of the magic of this channel has got to be the perfectly timed music ... it sucks me right in the mystery and gives me that near Hitchcok-like suspense of wondering what comes next ... makes me feel like I'm at the edge of my seat in amazement and wonderment!
Dude I have a PhD and you are better than all of my professors combined. I literally couldn't progress into theoretical physics and took experimental because I was missing these visualisations. All those cryptic tensor formulas make sense now, thank you.
I found your channel on a whim, and I haven't been able to stop watching your videos. Truly an incredible experience that even I can understand. Having no real science background, your channel has awakened something within me. Your videos have completely immersed me in the quantum realm, thanks!
Dear Octave, Alessandro + your esteemed audience, First of all, many sincere thanks for your collective efforts! "What is entropy? In what fields is it useful? And how does it explain the direction in which transformations occur? All these answers in 12 minutes!" ...sounds terrific, but this is definitely not for an average mind... ...Even big scientific research workers' brains had and still have to stumble herewith... Hence, some kind of a clarification ought to be urgently necessary! So, captain, AHOY! A. There is ONLY ONE BASIC, fundamental Energy Conservation and Transformation Law. It is definitely unique and conceptually indivisible delivering two logically joint concepts - these are Energy Conservation - and Energy Transformation. Still, a more-then-100-years-old conceptual failure has brought us to two separate thermodynamic laws - but this has nothing in common with the actual physics. To come back, they have coined two more fake thermodynamic laws, employed the Probability Theory + Mathematical Statistics, and this has helped formulate the Quantum Mechanics, which is thus a basically metaphysical conceptual construction - and, hence, ought to be only restrictedly fruitful. B. By dividing the basically indivisible law, you are touching Combinatorics, you are touching Probability Theory, you are even stepping back to Thermodynamics for a while, but... You are NOT answering the poser: WHAT IS ENTROPY, sorry! 1. In the formula S = kB * ln(Ω) you do imply, Ω means not a "Huge Number of Microstates", not "Probability", which numerically ranges between [0,1], not even "Wavefunction", which ought to be a purely metaphysical notion, as it is... In effect, Ω ought to be a simplistic algebraic function of Lord Kelvin's Absolute Temperature. This result has been published 100 years ago in JACS. 2. WHAT-ENTROPY-IS-poser has been answered not by Clausius, not by Boltzmann, etc., but by Goethe, who has introduced Mephistopheles, the philosophical embodiment of ENTROPY. 3. Newton did basically know WHAT ENTROPY IS - A Counteraction. 4. That Counteractions do not grow to infinity with the growing Actions, but MUST reach their MAXIMUM values, is the result by Nicky Carnot, which has been formalized by Clausius... 5. In effect, J. W. Gibbs Free Energy formula: (ΔG = U + pV - TS, .i.e., ΔG = H - TS, where U is the internal energy (SI unit: joule), p is pressure (SI unit: pascal), V is volume (SI unit: m3 = m*m*m), T is the temperature (SI unit: kelvin), S is the entropy (SI unit: joule per kelvin), H is the enthalpy (SI unit: joule)) renders implicit the interplay among ALL the relevant Actions (the Enthalpic term) and ALL the pertinent Counteractions (the Entropic term). 6. The standard approach you are reporting about is OK for the implicit Enthalpy-Entropy picture, employing it, e.g., for studying reaction mechanism details is likewise eating soup with a fork. The above is about 'Entropy' in Physics, Chemistry, Biology, etc., etc., etc. ... Entropy in other fields: Be aware of a powerful trend to build up misnomers in many other fields, for Entropy is the proper term solely for the "Energy Transformation", whatever nature/origin this energy might be of. The Arrow of Time: This is not due solely to Entropy, but owing to Eternal Entropy-Enthalpy Compensation. This is why, the Heat Death you are proclaiming over and over again ought to be just a useless legacy.🧐
A minor critique regarding the balloon example (6:39): Picking a balloon instead of a rigid container (eg an open bottle) makes the whole situation needlessly complicated and ambiguous. The balloon itself will go from a stretched/inflated to a relaxed/deflated state (and thereby pushing out whatever is inside), no matter how the air molecules are initially distributed within the whole system.
The balloon will ALSO relax due to entropy. If you stretch a rubber band, it will warm up. This is due to the relationship of temperature and entropy, where the temperature must go up if we go to a lower entropic state.
The idea is that the expansion of the universe increases its total volume, and hence it increases the maximum attainable entropy (entropy is proportional to volume). If this maximum increases fast enough, the universe might never reach it.
@@ScienceClicEN This would make for a great follow up video explainer. For me, naively, I've only heard of the dour conclusion that entropy and the eventual heat death of the universe would be the final conclusion. This has, as you know, pretty depressing philosophical consequences such as nihilism (e.g., why bother doing anything when it will all fall apart eventually?). Your cliffhanger in this video, was the only time (I'm not a physicist) that someone has alluded to the optimistic possibility that high entropy heat death is not the only possible ending. And not through hand-waving, but through the science of general relativity and the expansion of the universe. Wow.
As much as I absolutely ADORE your videos, I think this one does not explain entropy that well. For example, it does not explain pockets of low entropy (how does the balloon exist in the first place if space is increasing entropy?). It doesn't mention Brownian motion or why does the space fluctuate randomly. It also does not very much explain its relation to the arrow of time, which would probably need to be explained on more deep structures of the universe? The example of temperature does not seem sufficient to me as the entropy and heat death specifically are more about energy in general than heat. Sorry about the critique (not a physicist so take it with a grain of salt), I really love your videos.
I kinda agree with you. This is my favorite YT science channel and I'm a patreon. However I was expecting something more from this video and title, and ultimately I ended up with more questions than answers.
You can reverse entropy, locally, by bringing energy into a system, by "ordering" the system directly, that's what living systems do. This video just explains what entropy is and why a closed system left to itself will tend to always increase its entropy. Note that it's statistical, not absolute, nothing prevents the system from suddenly and randomly jump to a very low entropy state, the probability is just very (very) low. Some physicists think that the creation of the universe was one of this crazy chance events that brought entropy at crazy low levels. Given enough time even the most improbable will happen.
Been waiting for a video like this. Entropy is best understood is a heat tax and the reason why time only travels forward. To reverse time is to reverse physical processes, and a perfectly reversible process with no energy loss is not possible because a perfect insulator would imply it aborbs molecular collisions without absorbing energy.
I'm not sure that the explanation of the tendency for entropy to increase with time explains the arrow of time. The thought experiment (and discussion that follows) I first heard from Carlo Rovelli: Imagine removing the partition in the middle of a box separating vacuum and a uniform gas; allow the gas to evolve in time and it begins to partially fill out the previously empty space; before equilibrium is reached, say when the gas is "3/4 of the way to uniform" freeze time; if, then, we evolve forward in time, the expansion completes as expected, but, if instead we run time backwards, **the same thing happens**, the gas still evolves to a high entropy state, filling the container uniformly! So why do we associate an arrow of time with an increase with entropy? Because entropy was lower in the past. The gas was pumped into half the container using low entropy electricity generated by low entropy fuels that came from low entropy solar radiation and on and on back to the big bang. Why was entropy lower in the past? That is the mystery. Hopefully someone else remembers this argument better and can provide some links!
@@biblebot3947 "Before" and "became" are "time words" ... that is, they are only defined if you *already assume* an arrow of time. Otherwise, how would you know which direction was "before" and which direction was "became"?
@@biblebot3947 In the thought experiment, he's not saying that entropy "supposedly increased" when the arrow of time was reversed. Rather, he's saying that the *argument* for why entropy increases towards the future should logically equally well apply if you look at the picture "backwards", and entropy therefore *should* also increase towards the past ... and yet it doesn't. The Huw Price article (book, actually) which I linked to elsewhere says that way back when Boltzmann first introduced these various concepts, he (Boltzmann) also realized that his arguments *should* apply equally well when looked at in reverse -- entropy logically *should* increase towards the past, as well as towards the future -- and the real mystery is why it only increases in one direction. (And that the mystery is also why we happen to live in such a relatively low-entropy time.) That book explains Boltzmann's reasoning, Boltzmann's solution to the problem (which Price says was ultimately incorrect, but much closer to correct than anyone's solution until recently). The book does so far more clearly than I can do ... and in far more detail than I'm willing to attempt to give. ;^) So I strongly recommend it.
Basically, since low entropy is less likely than high entropy, the states *surrounding* a low entropy state *ought* to be higher entropy -- surrounding on *both* sides (I'll call them "left" and "right", rather than "past" and "future", just to avoid using words which already presuppose a direction of time).
This channel is really amazing.. Me on being an indian ,searched i was not getting any relevant video of indians...then i found this which explained the concept welll and in interpetable accent...
I heard it explained that this is why wired earbuds tend to get inextricably tangled in a pocket: there’s only one way for them to be untangled and nearly an infinite number of ways for them to be tangled. The likelihood of it being untangled is very low compared to any other configuration.
I can't believe you're only 23. It's one thing to have an educational background as impressive as yours, as well as talent with music and art. But the fact that you're able to write and produce things in such an explainable manner at such a young age is just prodigious. I thought originally that this must have been a team of people. I was shocked when I clicked your bio link.
entropy and the egg, essentially our newton's apple. dude blew my mind in 30 seconds, the egg CAN be put back together because we have more data for what it WAS! all it takes is a simple time swipe backwards with the correct parameters.. the universe is so fundamental when it clicks.
One technical issue at 1:22: the entropy is not assigned to a particular microstate but to a macrostate, being a collection of microstates. The more microstates belong to a macrostate, the higher the entropy of a macrostate. Hence, the image has no entropy; the correct way to express it is that it belongs to a higher-entropy macrostate. Similarly, see 5:00, Shannon’s entropy is a measure of an information source, not a particular message. Another issue: in the presence of gravitational field, the increase of entropy is not in line with increased homogeneity, it is the opposite. As time passes, gravity makes a homogenous gas more and more inhomogeneous. Anyway, the channel and the movie are fantastic.
Of the three images which one belongs to the macrostate with least entropy? Isn't it the homogenous image because it can be described with the fewest information out if the three.
I'm only at 7:43, but I want to pause to say I really appreciate your relation of entropy to physical experience, when you say that "physical systems tend to homogenize", instead of falling back on a circular argument like "time just passes". So many shows tend to link "entropy" and "time" in a philosophical or cultural way, but your script reminds us of the importance that "the physical intuition" or sensation or experience of a balloon, or boiling water or melting ice is at the core of discussions about entropy. You make this perspective so clear! ... And of course you have a great sidenote later to clarify that gravitational entropy and other things are still worth thinking about outside of this intuition
it's a classic for this channel to throw in a different topic at the end to keep you curious and aware of how much stuff the simple explanation is leaving out :D
Possibly, if you look up conformal cyclical cosmological (CCC) , By Sir Roger Penrose you'll get an idea. It's pretty hard to ' bore' a photon. Happy watching.
Maybe because if space itself is ever expanding while the total energy of the universe is unchanged that there will be an ever increasing number of possible states, i.e. ever increasing entropy?
@@heavy-gauge I dont think so. The universe will get to an equilibrium state, where nothing exists, All of the matter will disappear overtime and the system will reach its max entropy and the concept of time will disappear.
You simply don't cease to amaze, the conciseness of your videos is on a whole different league, and your ability to build up ideas in an intuitive way, with minimal and yet full context is pure teaching talent.
And for what? lol Some peoples are exploring some subjects, the others are exploring the different ones. It all depends on what peoples expect in life and how they aproach it. Some peoples love quantum physics and math, some music, art, the others military, craft etc. U cant be alpha and omega. U can say "bUt for tEh geNeRaL kNowLedg". Cmon, because someone do not know what is entropy in physics it doesnt rly change a thing. Every human is different.
I just finished your videos explaining general and special relativity and I have to say I was caught off guard by your natural talent as a teacher. Your videos are very impressive on their own, and you're ability to dive into such nuanced theories for 10-15 min at a time, without going on tangents or losing your focus, is what really makes you such an effective teacher in my mind. I genuinely understood 100% of all the things you said, which is not something I get out of any other videos from educational RU-vidrs like Vsauce, PBS Space Tme or Veritasium, even though they're titans with millions of subs and plenty of money and time. Other educational videos almost always start with a single topic, but become unintentionally superfluous as unnecessary tangential information is pilled on. You are laser focused, you'll give several extremely relevant, yet simple experiments that offer unique visual representations in order to shed more light on a single topic. You did this while covering general relativity when you visualized space-time in 3d while also using a warping grid to represent the passage of time as an apple falls towards earth. Considering your other videos and explanations, it's easy to see how creative, concise and coherent you are as a creator/educator overall. Serious props man, you're fantastic
Best video on entropy on YT! I’ve been looking, too, to help explain it to my high school son. As always, great work. Now just stop saying “further” when the correct word for physical distance is “farther” hahaha.
One of the best, maybe the best science channel, at least for GR. Entropy is a tricky topic and rightfully there is a disclaimer at 8:41: degree of (increasing) structure is many times confused with a degree of lower Entropy and vice versa: higher Entropy less Structure (also not true in general). E.g. two layers of oil and water phase separation (looking more structured) has higher Entropy relativ to an oil-water mix after shaking. I wish that this is the first of an introductory videos to that fundamental subject.
1:21 - I don't understand this part. If I used my own intuition, I would say that image 2 is the most orderly of them all. If I think of how much information is needed to describe each of the images, I would say that the empty image no. 2 needs the least amount of information. Then the image no.1 with an apple. And finally, image generated with random pixel variation needs the most information to be described. Empty image has every one of it's pixels painted white, while the random pixel image has every pixel painted differently. So they are clearly not the same thing, empty image is perfectly ordered, and randomized image is highly disordered. So my question is, why is the empty image in the same category as the random pixel image?
The idea is that on a large scale you don't distinguish the individual colour of each pixel, and therefore the random image just looks like a flat, structureless image. If you only look at big shapes and colours, only the image of the apple has details. And, therefore, the image of the apple contains *large scale information* while the other two don't. This implies that the image of the apple contains less *small scale information* than the other two images, and hence it has less entropy. Entropy measures the amount of information that is not visible at large scale, the amount of *small scale detail* which does not participate to any large scale structure.
Here is another question. When is an object large enough that we can say it has large scale information? Are these zoom levels arbitrary? If we could zoom out and look at the entire universe from some far away distance, it would look like a flat, structureless space.
I'm sorry Scienceclic, your videos are great, but, I don't follow the scale argument either. The scale is arbitrary. And how do you define structure. Just because the random image visually appears homogeneous and structureless when presented as an image doesn't mean it's actually structureless. If we translated all of Shakespeare's works into an image, it would appear like a jumble of noise, but that's just because you've chosen to look at it in a different medium. If you translated it back into characters, you'll see that it that had cast structure and information all along.
Surprised i wasn't the only one. i also chose that image to be the most ordered one because it seemed to have nothing going on for it, while the image with the static pixels seemed so aggregated and disordered, maybe that example was not the good fit, idk.
I like to think of entropy in terms of gradients and change. Gradients are self-neutralizing. There's a gradient => change occurs => the gradient ceases to exist => no more change is possible. All in all, there's only a finite amount of change that can occur in the universe. We just happen to be living in a time where that amount hasn't run out.
So, questions: if indeed, as we think, after the big bang but before the formation of particles, there was a uniform plasma-like energy throughout "existing" space, sort of pure energy, would not such a state have an enormous amount of entropy? so how come entropy is on the increase? Also entropy can only increase in a closed system, (second law). Does that imply the universe is finite?
Interesting, concise, clear. 10/10 I know a lot about entropy, but to have such a good and plain definition helps me understand it from a different point of view, which is the one that allows me to explain to someone that doesn't have my same knowledge as mine on the matter.
Right! i understand the concept of entropy but i can't seem to make it understand to my friends and friendly members when it comes to such discussions, i always find myself repeating and saying stuff like entropy always increases with time and everything tends to move to state of a Disorder bla bla but they don't understand a damn thing, lol.
It makes you wonder about boiling water at different altitudes; where air at high altitudes has a higher entropy which means reduced air pressure. This allows water to boil at lower temperatures than sea level because there is less dense air molicules holding down and preventing the entropy increasing by gravity. Its also why steam or heat rises rather than falls like dry ice vapour.
Excellent video! Since long I was confused about entropy but they video in minutes made me understand it! Ty. I just have one doubt: You are saying that the apple and the surrounding will become homogeneous in everyday life, so how much time will it require to do that? As I have never seen it happening and ig no one has.
It takes a very long time. Consider the apple and its surroundings as a structured cloud of molecules. The probability that this cloud eventually becomes randomly evenly distributed is higher than another complex structure to form, i.e. ending up with two smaller apples, just by chance. There are countless random configurations while there are just "a few" structured ones.
ScienceClic! I'm your new fan! I love watching Science videos, but trust me, you're the first ever Science channel I've subscribed to. Your explanations are spot on! To a point that is just right for me. Can you do dark matter/energy next time? Videos from other channels just don't suffice for me for some reason, and I hope that you'd consider!
The macroscopic description of entropy is thermodynamics while the microscopic description is statistical mechanics. And so homogeneous structures (macrostates) are far more likely to come up in a random set because they have incomparably more microstates than ordered low entropy structures
