Was ist Entropie? - Martin Buchholz - Science Slam

Today, ladies and gentlemen, I would like to give you a little idea of ​​a size that is probably completely unknown to some of you, to others it is at best an abstract concept without any reference to the reality of your life and therefore that. I'm starting with something that everyone probably knows. It's very easy to think of it in the title: a cooling tower, but the much more interesting question should be: what are cooling towers for, why is there a cooling tower next to each one? Why do you need cooling towers? What do you think the lady's laugh is like?

You can cool cooling towers, of course you have a first class answer and I hope it will always be in the same league as before. something to do with residual heat or especially when there are small children there. Well, maybe first we should be clear about what's going on. Your power plant really happens in a power plant. Electricity can now be produced, but not so easily. nothing and hopefully go to school about the law of conservation of energy, we call this the first law of thermodynamics and there we discover that energy is different, it can take forms, it can be changed between these forms, but it cannot be created nor be destroyed out of nothing. , that is, what happens to a power plant is that probably some other form of energy is converted into electricity and these other forms of energy are usually heat and therefore also have Every power plant, whether coal or nuclear atomic plants gas, There is always a combustion chamber in which the decaying uranium or the combustion of coal generates heat and this is then converted into electricity in the actual power plant process, so I decided to use energy times as large as red balls in this conference.

It doesn't matter what form it has, it doesn't matter if it is heat, electricity or anything else. The energy is big red balls. In order not to violate the law of conservation of energy, we just have to be careful not to do so. lose the big red balls Of course it's not necessary, I mean seriously, now we're going to build this combustion chamber to really heat it properly and make it really nice and warm, when it gets really hot, then we'll build a cooling system. tower What do people want in the power plant? Do you want the clouds?

Electricity maybe too warm for him or solar energy or they have burned too much coal, more heat than they need for electricity. That all sounds more or less like this and The problem is that we are too focused on this size all the time. Pay attention to energy. There is another quantity that is at least as important, you can imagine the entropy of this quantity. I know something about the second law of thermodynamics, first of all, that this quantity exists, that there is entropy in every body and that from one body to another the entropy can be exchanged along with heat because whenever I use it, the entropy stale en It is transferred and when the entropy is transported, it is heated by the hand, the special thing is that the relationship between the heat transferred and the temperatures transferred and the entropy transferred.

That's not about it being constant, being equal to the temperature. Now I see that that's what. It always happens that the first ones start to frown, which is pretty good so far, but now the engineer is unpacking the formulas, but I can promise you, ladies and gentlemen, that here, if I may say so, is the mathematical climax of my career. lecture, so something like that again, it's not that hard, it really just looks like we're transferring heat at a high temperature, there's just a little bit of entropy in and when we transfer heat at a low temperature.

The last thing we learn is that entropy, unlike energy, cannot simply arise from nothing. On the contrary, this applies, by the way, it must not be destroyed and, as a small anticipation of the later, this production of entropy is technical. The processes are not particularly welcome, they are. It is always an indication that something in the process is not quite right in imperfect German. They have learned a lot about equipment and have not learned what entropy really is. There's a lot of meaning that goes into it. with differences or uniformity, since you probably know that entropy is a measure of disorder like measure, so I don't think it's that special, but I would like to give you some advice on what you should imagine using entropy, ladies and gentlemen, if you can .

If you follow these three points that we have behind me on the screen, then you will be able to solve problems that most of your peers will remain hidden until the end of your days. And if now you say I have to imagine something, I can't work with a size, I can't imagine anything about it, then think about blue balls less. That's a good way to get to the point of this newly acquired knowledge, which is what we want to do now and apply it. to our power plant that comes from the burns you can get heat in the power plant that we have, it is always transported hand in hand with entropy, so for a few pellets the cyclone then the electricity reaches the consumer, well, electricity is not heat, so no pellets. any and that's it, well now you have a situation where entropy goes into the power plant but no longer comes out.

Yes, it's bad, even if they don't know exactly what this entropy really is, you can also easily imagine it. which is not good for any power plant in the world. It could be a man who has had blue balls enter for years and come out again. We have to get rid of them somehow. How do we get them out? We took them out like we put them in and now I think the first one is the man and her? We see the cooling tower already around the corner. We need the cooling tower to send the direction of entropy along with the heat. now this heat is sent in this direction.

The cooling tower is no longer available to produce electricity from it, so the electricity output is falling. Why is there still electricity? I mean, we also want to send all the entropy that comes from the combustion chamber to the cooling tower. We don't have to use all the heat. Fortunately, we don't remember the mixing ratio, you can really burn nice and hot while the cooling tower is pleasantly cold and. that means that the heat burning from the can comes from the small entropy transported and at the low temperature of the cooling tower, some of the heat is enough to dissipate all the entropy and we can convert the rest into electricity.

Do two things, firstly, you can create a power plant that produces electricity and secondly, you took the ideal meeting point where all the physicists, all the engineers, all the construction workers really do a perfect job. Yes, we will always have to send the entropy towards the cooling tower. which means we will never convert all the heat into electricity, it can also be converted into an ideal power plant, so when I talk about a medium power plant, you can already hear through the flower that it is probably not a power plant. ideal energy. If you live next to a power plant, it tells me that it is not an ideal power plant because not everything goes well and that means that when everything goes well, entropy is produced and this produces entropy, which has two consequences.

The first consequence is relatively obvious, this extra entropy that we have to get rid of again, what do we do with that? We also send them to the cooling tower, but they want to act. , don't you know, that means our electricity output continues to decline. A real power plant has a worse efficiency, an ideal so far that is practical and now we come to the somewhat philosophical point that concludes my lecture on this entropy. production in the power plant which leads to the entire process of converting heat into electricity becoming irreversible. Before it was reversible. Let's look at the ideal power plant again and five units of entropy also come out, that is, the light of the.

First and second law. This process could also work differently. There's nothing wrong with that if I don't know if anyone would pay anyone to operate a power plant like that, but it would work like that. But at the time we produce. Five units of entropy go into the copies but seven come out. We would reverse the process, seven would enter and five would leave. This would only work in the long run if the entropy in the plant was destroyed. and therefore the entire process is irreversible. The production of entropy increases quite esoterically or if I would like to go a step further and say that entropy and two sisters are always running in one direction, yes, in the direction in which the total entropy of the universe increases. yes, all our concepts of before and after, only through the production of entropy and the associated irreversibility of things acquire meaning.

The good thing about this is that, obviously, entropy and time have something to do with each other and they show it. It is a concept that we know and that leads us to also be in favor of the production of entropy. I have a very good feeling, so when protesting some always say hello. Five minutes ago I didn't know this size because now I should. I have a feeling for entropy productions and that's exactly what I want to show you in the remaining minute and a half. I have three fragments of short films divided into two.

In these film fragments a lot of entropy is produced that makes noise and in the third one there is almost none. On the one hand, we see a browser glass that draws you in a little faster. They throw the pure snowboard at you a little and at the end they drink it drinking a delicious glass of already prepared. fizzybrew in raspberry maybe browser in the second video you can see how a pendulum made of handlebars swings back and forth a little and in the third video you can see what my godson does with the same pendulum and a tower that the father babies are always cute but some of them will still wonder and say where is the feeling.

I don't feel at all where Tropez takes place. I'll wait a moment, we'll do another thought experiment, let's imagine we leave one of the processes. Those who produce. If the entropy in the forward movement was executed backwards, then the entropy would have to be destroyed, but that is prohibited. What no one, not even the second law of thermodynamics, can prohibit us from is letting your movie run backwards, so what we can see is what will happen. being in Nature does not give that and it will look natural and it is not necessary to have studied mechanical engineering or physics to say that something like that simply does not happen and even with the browser glass it seems quite acceptable in the but at the latest when all these citizens bubble and all the dyes begin to contract again inside the glass, at the latest you will look and say no, that only exists in the movie.

In the last movie it looks completely different, this too. movie, that I run back, but I have to say that because you can't see it. Why can't you see it? The swinging of a frictionless pendulum is a process that takes place with almost no entropy production and therefore has no clearly defined beginning nor clearly defined end. Unlike my conference, I would like to thank you for your attention. I hope you recognized that the first law of the energy attitude theorem just a boring counter because the big red energy. share update, but the second one, to stay in the picture, represents the management that decides in which direction the processes are executed and last but not least, I hope that the next time you pass by a power plant you no longer have You wonder if the people there are too warm, but you tell yourself quietly releasing entropy, even if you can't see the little blue balls, of course, thank you